UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 10-K

Commission File Number: 001‑33480

CLEAN ENERGY FUELS CORP.

(Exact name of registrant as specified in its charter)

4675 MacArthur Court, Suite 800, Newport Beach, CA 92660 
(Address of principal executive offices, including zip code)

(949) 437‑1000 
(Registrant’s telephone number, including area code)

Securities registered pursuant to Section 12(b) of the Act:

Securities registered pursuant to section 12(g) of the Act: None

Indicate by check mark if the registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act. Yes  ☐     No   ☒

Indicate by check mark if the registrant is not required to file reports pursuant to Section 13 or Section 15(d) of the Act. Yes  ☐     No   ☒

Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days. Yes   ☒     No  ☐

Indicate by check mark whether the registrant has submitted electronically every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation S-T (§229.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit such files). Yes  ☒     No  ☐

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company, or an emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer,” “smaller reporting company,” and “emerging growth company” in Rule 12b‑2 of the Exchange Act.

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐

Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b‑2 of the Act). Yes  ☐     No  ☒

The aggregate market value of the voting stock held by non-affiliates of the registrant as of June 28, 2019, the last business day of the registrant’s most recently completed second fiscal quarter, was approximately $535,652,621 based on the closing price of the registrant’s common stock of $2.67 per share on that date. The treatment of persons as affiliates of the registrant for purposes of this calculation is not, and shall not be considered, a determination as to whether any such person is an affiliate of the registrant for any other purpose.

As of March 4, 2020, there were 205,583,627 shares of the registrant’s common stock, par value $0.0001 per share, issued and outstanding.

DOCUMENTS INCORPORATED BY REFERENCE

Portions of the registrant’s definitive proxy statement for its 2020 annual meeting of stockholders are incorporated by reference in Part III of this report.

Clean Energy Fuels Corp.

Annual Report on Form 10‑K

For the Fiscal Year Ended December 31, 2019

TABLE OF CONTENTS

CAUTIONARY NOTE REGARDING FORWARD-LOOKING STATEMENTS

This annual report on Form 10‑K contains “forward-looking statements” within the meaning of Section 27A of the Securities Act of 1933, as amended (the “Securities Act”), and Section 21E of the Securities Exchange Act of 1934, as amended (the “Exchange Act”). Forward-looking statements are statements other than historical facts. These statements relate to future events or circumstances or our future performance, and they are based on our current assumptions, expectations and beliefs concerning future developments and their potential effect on our business. In some cases, you can identify forward-looking statements by the following words: “if,” “may,” “might,” “shall,” “will,” “can,” “could,” “would,” “should,” “expect,” “intend,” “plan,” “goal,” “objective,” “initiative,” “anticipate,” “believe,” “estimate,” “predict,” “project,” “forecast,” “potential,” “continue,” “ongoing” or the negative of these terms or other comparable terminology, although the absence of these words does not mean that a statement is not forward-looking. The forward-looking statements we make in this report include statements about, among other things:

The preceding list is not intended to be an exhaustive list of all of the topics addressed by our forward-looking statements. Although the forward-looking statements we make reflect our good faith judgment based on available information, they are only predictions of future events and conditions. Accordingly, our forward-looking statements involve known and unknown risks, uncertainties and other factors that may cause our or our industry’s actual results, levels of activity, performance or achievements to be materially different from any future results, levels of activity, performance or achievements expressed or implied by our forward-looking statements. Factors that might cause or contribute to such differences include, among others, those discussed in Item 1A. Risk Factors of this report, as such factors may be amended, supplemented or superseded from time to time by other reports we file with the Securities and Exchange Commission (the “SEC”). In addition, we operate in a competitive and rapidly evolving industry in which new risks emerge from time to time, and it is not possible for us to predict all of the risks we may face, nor can we assess the impact of all factors on our business or the extent to which any factor or combination of factors could cause actual results to differ from our expectations. As a result of these and other potential risks and uncertainties, our forward-looking statements should not be relied on or viewed as guarantees of future events or conditions.

All of our forward-looking statements speak only as of the date they are made and, except as required by law, we undertake no obligation to update publicly any forward-looking statements for any reason, including to conform these statements to actual results or to changes in our expectations. You should, however, review the factors and risks we

describe in the reports we will file from time to time with the SEC for the most recent information about our forward-looking statements and the risks and uncertainties related to these statements.

We qualify all of our forward-looking statements by this cautionary note.

* * * * * * *

Unless the context indicates otherwise, all references to “Clean Energy,” our “Company,” “we,” “us,” or “our” in this report refer to Clean Energy Fuels Corp., together with its majority and wholly owned subsidiaries.

We own registered or unregistered trademark or service mark rights to Redeem™, NGV Easy Bay™, Clean Energy™, Clean Energy Renewables™, Zero Now, and Clean Energy Cryogenics™. Although we do not use the “®” or “™” symbol in each instance in which one of our trademarks appears in this report, this should not be construed as any indication that we will not assert our rights thereto to the fullest extent under applicable law. Any other service marks, trademarks and trade names appearing in this report are the property of their respective owners.

Investors and others should note that we disseminate information to the public about our Company, our products, services and other matters through various channels, including our website (www.cleanenergyfuels.com), SEC filings, press releases, public conference calls and webcasts, in order to achieve broad, non-exclusionary distribution of information to the public. We encourage investors and others to review the information we make public through these channels, as such information could be deemed to be material information.

PART I

Item 1.   Business.

Overview

We are North America’s leading provider of the cleanest fuel for the transportation market, based on the number of stations operated and the amount of gasoline gallon equivalents (“GGEs”) of RNG, CNG and LNG delivered. Through our sales of Redeem™ RNG, which is derived from biogenic methane produced by the breakdown of organic waste, we help thousands of vehicles, from airport shuttles to city buses to waste and heavy-duty trucks, to reduce their amount of climate-harming greenhouse gas by at least 70% and up to 300% depending on the source of the RNG feedstock. Redeem RNG is delivered as CNG and LNG; sales of our Redeem RNG have increased dramatically, from 13.0 million GGEs in 2013 (the year we introduced Redeem RNG to the vehicle fuel market) to 143.3 million GGEs in 2019.

Our principal business is supplying RNG, CNG and LNG for medium and heavy-duty vehicles and providing operation and maintenance (“O&M”) services for public and private vehicle fleet customer stations. As a comprehensive solution provider, we also design, build, operate and maintain fueling stations; sell and service natural gas fueling compressors and other equipment used in CNG stations and LNG stations; offer assessment, design and modification solutions to provide operators with code-compliant service and maintenance facilities for natural gas vehicle fleets; transport and sell CNG and LNG via “virtual” natural gas pipelines and interconnects; procure and sell RNG; sell tradable credits we generate by selling RNG and conventional natural gas as a vehicle fuel, including RIN Credits and LCFS Credits; help our customers acquire and finance natural gas vehicles; and obtain federal, state and local tax credits, grants and incentives. In addition, before March 31, 2017, we produced RNG at our own production facilities (which we sold, along with certain of our other RNG production assets to BP Products North America (“BP”), in a transaction we refer to as the “BP Transaction”), and before December 29, 2017, we manufactured natural gas fueling compressors and other equipment used in CNG stations (which we combined with SAFE S.p.A., the natural gas fueling compressor subsidiary of Landi Renzo S.p.A. (“LR”) in a newly formed company, SAFE&CEC S.r.l., in a transaction we refer to as the “CEC Combination”).

We serve fleet vehicle operators in a variety of markets, including heavy-duty trucking, airports, refuse, public transit, industrial and institutional energy users, and government fleets. We believe these fleet markets will continue to present a growth opportunity for natural gas vehicle fuel for the foreseeable future. As of December 31, 2019, we serve over 1,000 fleet customers operating over 48,000 natural gas vehicles, and we own, operate or supply approximately 550 natural gas fueling stations in 41 states in the United States and four provinces in Canada. We estimate our number of stations is approximately three times the number of CNG fueling stations operated by our largest competitor in today’s market, and we believe our natural gas fueling operations cover more states and provinces than any of our competitors. We believe we are the only company in the United States or Canada that provides RNG, CNG and LNG vehicle fuel on a significant scale.

Market for RNG, CNG and LNG as a Vehicle Fuel

Natural Gas Vehicles for America (“NGV America”) estimates that, as of December 31, 2019, there were approximately 1,750 natural gas fueling stations in the United States and more than 175,000 natural gas vehicles on American roads.

We believe the following benefits of natural gas fuel drive the development of the market for RNG, CNG and LNG as a vehicle fuel in the United States:

Cleaner.    RNG vehicle fuel has enhanced environmental benefits relative to gasoline and diesel vehicle fuels. The California Air Resources Board (“CARB”) has determined that RNG reduces the amount of climate-harming greenhouse gas by at least 70% and up to 300%, depending on the RNG feedstock, compared to gasoline and diesel. Simply put, RNG can be a carbon negative vehicle fuel

In addition, natural gas produces fewer carbon dioxide emissions than any other fossil fuel when burned. CARB has concluded that vehicles fueled by conventional natural gas produce between 12% and 22% fewer greenhouse gas emissions than comparable gasoline and diesel fueled vehicles.

Further, natural gas engines now commercially available for heavy-duty, regional-haul, refuse, transit and vocational applications have been certified to CARB and the U.S. Environmental Protection Agency (“EPA”) optional low NOx emission standard of 0.02 g/bhp-hr. This means that these engines emit 90% less smog-forming nitrogen oxides (also known as “NOx”) than the existing regulatory standards, making them the lowest certified ultra-low NOx emission engines in North America. We therefore believe vehicles equipped with ultra-low NOx engines that are fueled with RNG are the cleanest commercially available vehicles in North America (in terms of greenhouse gas emissions and NOx).

We expect our sales of Redeem RNG and conventional natural gas to grow as more companies look to operate in an increasingly sustainable way. In addition to pressure from politicians, regulators and non-governmental organizations, the investment community has dramatically stepped up demands on companies to diminish their contributions to climate change. We believe that RNG is the best tool available today to reduce climate-harming greenhouse gas and meet sustainability objectives.

By way of example, in January 2020, Microsoft announced that it will be carbon negative by 2030, and that by 2050 it will remove from the environment all the carbon Microsoft has emitted either directly or by electrical consumption since it was founded in 1975.  We believe that by 2027, Microsoft can be carbon negative and offset all of its post-1975 carbon emissions if it adopts 100% carbon negative RNG.

Domestic and Plentiful Supply.    Technological advances in production have unlocked supplies of RNG and vast conventional natural gas reserves. The United States has proven, abundant and growing reserves of natural gas, and produces the highest volume of natural gas in the world.

Less Expensive.    The cost of RNG, CNG and LNG in the United States is less than the cost of crude oil on an energy equivalent basis. Based on projections from the U.S. Energy Information Administration, we believe RNG, CNG and LNG will remain cheaper than gasoline and diesel for the foreseeable future. In addition, because the price of the commodity makes up a smaller portion of the cost of a GGE of RNG, CNG or LNG relative to the commodity portion of the cost of a GGE of diesel or gasoline, the price of a GGE of RNG, CNG or LNG is less sensitive to increases in the underlying commodity cost.

Safer.    As reported by NGV America, RNG, CNG and LNG are relatively safer than gasoline and diesel because they dissipate into the air when spilled or in the event of a vehicle accident. When released, RNG, CNG and LNG are also less combustible than gasoline or diesel because they ignite only at relatively high temperatures. The fuel tanks and systems used in natural gas vehicles are subjected to a number of federally required safety tests, such as fire, environmental hazard, burst pressure and crash testing, according to the U.S. Department of Transportation National Highway Traffic Safety Administration. RNG, CNG and LNG are stored in above-ground tanks and therefore will not contaminate soil or groundwater in the event of a spill or leak.

Natural Gas Vehicles

Natural gas vehicles use internal combustion engines similar to those used in gasoline- or diesel-powered vehicles, and the acceleration and other performance characteristics of natural gas vehicles are also similar to those of gasoline- or diesel-powered vehicles of the same weight and engine class. Natural gas vehicles, whether they run on RNG, CNG or LNG, are refueled using a hose and nozzle that makes an airtight seal with the vehicle’s fuel tank.

Natural gas vehicles have engines specially tuned to run on natural gas fuels, which has a higher octane number than gasoline or diesel, and fuel tanks and lines specially designed to hold RNG, CNG and LNG and deliver it to the vehicle’s engine. These special features, including principally the fuel tanks that hold RNG, CNG and LNG, cause natural gas vehicles to typically cost more than comparable gasoline- or diesel-powered vehicles. Additionally, for heavy-duty vehicles, spark-ignited natural gas vehicles operate more quietly than comparable diesel-powered vehicles. Due to improvements in diesel engine technology, natural gas vehicles may be somewhat less efficient than diesel vehicles in terms of miles per gallon, depending upon the application.

Virtually any car, truck, bus or other vehicle is capable of being manufactured or modified to run on natural gas. Many types and models of heavy-, medium- and light-duty natural gas vehicles and engines are available in the United States

and Canada, including, among others, long-haul tractors, refuse trucks, regional tractors, transit buses, ready-mix trucks, delivery trucks, vocational work trucks, school buses, shuttles, passenger sedans, pickup trucks and cargo and passenger vans. We expect additional types and models of natural gas vehicles to become available if adoption of RNG and conventional natural gas as a vehicle fuel becomes more widespread in the United States.

Our Products, Services and Other Business Activities

Our principal products, services and other business activities are described below. Information about the revenue we receive from these activities is discussed in this report in Item 7. Management’s Discussion and Analysis of Results of Operations and Financial Condition.

CNG Sales.    CNG is RNG and conventional natural gas that is compressed and dispensed in gaseous form. CNG is typically delivered by obtaining natural gas from local utilities or third-party marketers and then compressing and storing it at a fueling station and dispensing it directly into a vehicle. Some of the natural gas we obtain from third parties for CNG sales is purchased under take-or-pay contracts that require us to purchase minimum volumes of natural gas.

We sell CNG for use as a vehicle fuel through fueling stations located on our customers’ properties and through our network of public access fueling stations. Our CNG vehicle fuel sales are made primarily through contracts with our customers. Under many of these contracts, pricing is determined on an index-plus basis, which is calculated by adding a margin and delivery cost to the local index or utility price for natural gas. As a result, CNG vehicle fuel sales determined by an index-plus methodology increase or decrease as a result of an increase or decrease in the cost of natural gas, including transportation charges, utility costs and other fees. The remainder of our CNG vehicle fuel sales are made on a per fill-up basis at prices we set at public access fueling stations based on prevailing market conditions.

Through our subsidiary NG Advantage, LLC (“NG Advantage”), we also transport and sell CNG for non-vehicle purposes via virtual natural gas pipelines and interconnects. NG Advantage transports CNG to industrial and institutional energy users that do not have direct access to natural gas pipelines. NG Advantage also transports CNG between pipelines for customers that desire to take advantage of commodity price differences. NG Advantage uses a fleet of 113 high-capacity tube trailers to transport CNG.

LNG Production and Sales.    LNG is RNG and conventional natural gas that is cooled at a liquefaction facility to approximately -260 degrees Fahrenheit until it condenses into a liquid. We obtain LNG from our own liquefaction plants and from third-party suppliers. We own and operate LNG liquefaction plants near Boron, California and Houston, Texas, which we call the “Boron Plant” and the “Pickens Plant” respectively. The Boron Plant can produce 60.0 million gallons of LNG per year and has a dual tanker trailer loading system and a 1.8 million gallon storage tank that can hold up to 1.5 million usable gallons. The Pickens Plant can produce 35.0 million gallons of LNG per year and includes a tanker trailer loading system and a 1.0 million gallon storage tank that can hold up to 840,000 usable gallons. In 2019, we purchased 14.5% of our LNG from third-party suppliers and we produced the remainder of our LNG at our plants.

We sell LNG for use as a vehicle fuel on a bulk basis to fleet customers, who often own and operate their fueling stations, and through our network of public access fueling stations. We deliver LNG via our fleet of 74 tanker trailers to fueling stations, where it is stored and then dispensed in liquid form into vehicles. We contract with third parties to provide tractors and drivers. The need to liquefy and transport LNG generally causes LNG to cost more than CNG. We sell LNG through supply contracts that are priced on an index-plus basis, such that LNG sales under these contracts increase or decrease as a result of an increase or decrease in the cost of natural gas. We also sell LNG vehicle fuel on a per fill-up basis at prices we set at public access fueling stations based on prevailing market conditions. Additionally, we sell LNG for non-vehicle purposes, including to customers who use LNG in oil fields, and for utility, industrial, marine and rail applications.

RNG Sales.    RNG is delivered as CNG or LNG. It is produced from organic waste at landfills, animal waste digesters, wastewater treatment plants and other locations. RNG is injected into natural gas pipelines, which allows RNG to be transported to vehicle fueling stations where it can be compressed and dispensed as CNG, and to LNG liquefaction facilities where it is converted to LNG. We purchase RNG from BP and other third-party producers, and we sell that RNG for vehicle fuel use through our fueling infrastructure under the brand name Redeem™.

Sales of RINs and LCFS Credits.   We generate RIN Credits when we sell RNG for use as a vehicle fuel in the United States, and we generate LCFS Credits when we sell RNG and conventional natural gas for use as a vehicle fuel in California and Oregon. We sell these credits to third parties who need the RINs and LCFS Credits to comply with federal and state emissions compliance requirements. Generally, the amount of RINs and LCFS Credits we generate increases as we sell higher volumes of RNG and conventional natural gas as a vehicle fuel; however, the amount of credits we sell and our revenue from these sales can vary depending on a number of factors, including the market for these credits, which has been volatile and subject to significant price fluctuations in recent periods (in 2019 market prices for RINs were as high as approximately $1.90 and as low as approximately $0.50), any changes to the federal and state programs under which the credits are generated and sold, and our ability to strictly comply with these programs.

O&M Services.   We perform O&M services for fueling stations that we do not own. For these services, we generally charge a fixed or a per-gallon fee based on the volume of fuel dispensed at the station. We have an operations team that performs preventive maintenance and is available to respond to service requests.

Station Construction and Engineering.    We design and construct fueling stations and facility modifications and sell or lease some of these stations to our customers. We charge construction or other fees or lease rates based on the size and complexity of the project. Since 2008, we have served as the general contractor or supervised qualified third-party contractors to build over 420 natural gas fueling stations. We use a combination of custom designed and off-the-shelf equipment to build fueling stations. Equipment for a CNG station typically consists of dryers, compressors, dispensers and storage tanks; equipment for a LNG station typically consists of storage tanks, pumps and dispensing equipment. Many of our fueling stations have separate public access areas for retail customers, which generally have the look, feel and dispensing rates of gasoline and diesel fueling stations. We also offer assessment, design and modification solutions to provide operators with code-compliant service and maintenance facilities for natural gas vehicle fleets. For example, our NGV Easy Bay product is a natural gas vapor leak barrier developed specifically for natural gas vehicle facilities.

Vehicle Acquisition and Finance.    We offer vehicle finance services, including loans and leases, to help our customers acquire natural gas vehicles. As appropriate, we apply for and receive federal, state and local incentives associated with natural gas vehicle purchases and pass these benefits through to our customers. We may also secure vehicles to place with customers and/or pay deposits with respect to these vehicles before receiving a firm order from our customers, which we may be required to purchase if our customers fail to purchase the vehicle as anticipated.

Grant Programs.    We apply for and help our fleet customers apply for federal, state and local grant programs in areas in which we operate. These programs can provide funding for natural gas vehicle conversions and purchases, natural gas fueling station construction and natural gas vehicle fuel sales.

Former Activities.    Before March 31, 2017, we produced at our own production plants a portion of the RNG that we sold. On March 31, 2017 we completed the BP Transaction, in which we sold to BP certain assets related to this RNG production business, including two RNG production facilities, a 50% ownership interest in joint ventures formed to develop two new RNG production facilities, and third-party RNG supply contracts.

Before December 29, 2017, we, through our former subsidiary IMW Industries Ltd. (formerly known as Clean Energy Compression Corp.) (“CEC”), manufactured natural gas fueling compressors and other equipment used in CNG stations. On December 29, 2017 we completed the CEC Combination, in which we combined CEC with SAFE S.p.A, the natural gas fueling compressor subsidiary of LR, in a new company, SAFE&CEC S.r.l. SAFE&CEC S.r.l. is focused on manufacturing, selling and servicing natural gas fueling compressors and related equipment for the global natural gas fueling market. We and LR own 49% and 51%, respectively, of SAFE&CEC S.r.l.

Customer Markets

We serve customers in a variety of markets, including trucking, airports, refuse, public transit, industrial and institutional energy users and government fleets. We believe these customer markets are well-suited for the adoption of natural gas vehicle fuel because they consume relatively high volumes of fuel, refuel at centralized locations or along well-defined routes and/or are facing increasingly stringent emissions or other environmental requirements. During the years

ended December 31, 2017, 2018, and 2019, no single customer accounted for 10% or more of our total revenue. See Note 22 for additional information

Trucking. We believe heavy-duty trucking represents the greatest opportunity for natural gas to be used as a vehicle fuel in the United States, and as of December 31, 2019, we fuel over 4,000 heavy-duty trucks. Because these high-mileage vehicles consume substantial amounts of fuel, they can derive significant benefits from the lower cost of natural gas. We are focused on fueling more natural gas heavy-duty trucks, and many well-known shippers, manufacturers, retailers and other truck fleet operators have started to adopt natural gas fueled trucks to move their freight. Companies that have adopted natural gas fueled trucks include Pepsi Frito-Lay, FedEx, Anheuser-Busch, USPS, Bimbo Bakeries, UPS, MillerCoors, Unilever, Kroger, P&G, KeHe and Owens Corning.

Zero Now. To help facilitate the transition of trucking fleets to natural gas, we have launched the Zero Now truck financing program, which is intended to increase the deployment of the commercially available ultra-low NOx natural gas heavy-duty trucks in the United States and encourage these operators to fuel their trucks at our stations. The Zero Now program generally involves the following:

We have entered into the following agreements to implement the Zero Now program:

For more information about the Zero Now program and the related agreements, see “Item 1A. Risk Factors” and Note 13.

In addition, we are supporting the growth of the natural gas heavy-duty truck market through our negotiation of favorable CNG and LNG fuel tank pricing from manufacturers, which we are passing along to our customers, and our network of natural gas truck-friendly fueling stations (we refer to this network as “America’s Natural Gas Highway” or

“ANGH”), which we have built in key locations nationwide. Many existing ANGH stations are located at Pilot Travel Centers, the largest truck fueling operator in the United States.

Airports. We estimate that vehicles serving airports in the United States, including airport delivery fleets, rental car and parking passenger shuttles and taxis, consume an aggregate of approximately two billion gallons of fuel per year. Additionally, many U.S. airports face emissions challenges and are under regulatory directives and political pressure to reduce pollution, particularly as part of any expansion plans. As a result, many of these airports have adopted various strategies to address tailpipe emissions, including rental car and hotel shuttle consolidation and requiring or encouraging service vehicle operators to switch their fleets to natural gas. To assist in this effort, airports are contracting with service providers to design, build and operate natural gas fueling stations in strategic locations on their properties.

As of December 31, 2019, we serve customers at 39 airports, including Atlanta Hartsfield Jackson International, Baltimore Washington International, Dallas-Ft. Worth International, Denver International, Dulles International (Washington D.C.), George Bush International (Houston), Las Vegas, Logan International (Boston), LaGuardia (New York City), John F. Kennedy International (New York City), Los Angeles International, Newark International, Oakland International, Orlando, Phoenix Sky Harbor International, San Francisco International, San Diego International, SeaTac International (Seattle) and Tampa International.

Refuse. According to INFORM, there are nearly 200,000 refuse trucks in the United States that collect and haul refuse and recyclables, which collectively consume approximately two billion gallons of fuel per year. We estimate that approximately 55% of new refuse trucks in 2019 operate on natural gas, up from approximately 3% of new refuse trucks in 2008. Refuse haulers are increasingly adopting trucks that run on RNG and CNG to realize operational savings and to address their customers’ demands for reduced emissions.

As of December 31, 2019, we fuel over 13,000 refuse vehicles for customers including Waste Management and Republic Services, as well as other waste haulers such as Atlas Disposal, Burrtec, Recology, Waste Connections and Waste Pro, among others. We also provide vehicle fueling services to municipal refuse fleets, including fleets in Dallas, Los Angeles, San Antonio and New York City, among other locations.

Public Transit. According to the American Public Transportation Association, there are over 66,000 municipal transit buses operating in the United States. In many areas, increasingly stringent emissions standards have limited the fueling options available to public transit operators. Also, transit agencies typically fuel at a central location and use high volumes of fuel. We estimate that transit agencies in the United States consume approximately 1.0 billion gallons of fuel per year. Many transit agencies have been early adopters of natural gas vehicles, and over 25% of existing transit buses and over 35% of new transit buses operate on natural gas.

As of December 31, 2019, we fuel over 9,000 transit vehicles for customers including Los Angeles County Metropolitan Transit Authority, Foothill Transit (Los Angeles County, California), Orange County Transit Authority, Santa Monica Big Blue Bus, Dallas Area Rapid Transit Phoenix Transit, New Jersey Transit, Jacksonville Transportation Authority, NICE Bus (Nassau County, New York) and Washington Metro Area Transportation Authority, as well as public transit customers in British Columbia.

Industrial and Institutional Customers. NG Advantage uses its virtual natural gas pipelines and interconnects to serve a number of customers that do not have direct access to natural gas pipelines or desire to take advantage of commodity price differences. We also transport LNG to customers via virtual natural gas pipelines.

Government Fleets. In 2017, 2018 and 2019, contracts with government entities, such as municipal transit fleets, accounted for approximately 19%, 22% and 21% of our revenue, respectively.

Our representative government fleet customers include the California Department of Transportation, State of New York, State of Colorado, City of New York, City of Denver, City and County of Los Angeles, City of Newport Beach, South Coast Air Quality Management District (Southern California region), City and County of San Francisco, City of Oakland, City and County of Dallas, City of Phoenix, The University of California, and Oklahoma State University.

Competition

The market for vehicle fuels is highly competitive. We believe the biggest competition for RNG, CNG and LNG use as a vehicle fuel is gasoline and diesel because the vast majority of vehicles in our key markets are powered by these fuels. We also compete with suppliers of other alternative vehicle fuels, including renewable diesel, biodiesel and ethanol, as well as producers and fuelers of alternative vehicles, including hybrid, electric and hydrogen-powered vehicles. Additionally, our stations compete directly with other natural gas fueling stations and indirectly with electric vehicle charging stations and fueling stations for other vehicle fuels.

A number of established businesses are in the market for natural gas and other alternatives for use as vehicle fuel, including alternative vehicle and alternative fuel companies, refuse collectors, industrial gas companies, truck stop and fuel station owners, fuel providers, utilities and their affiliates and other organizations. If the alternative vehicle fuel market grows in the future, then the number and type of participants in this market and their level of capital and other commitments to alternative vehicle fuel programs could increase. We believe there are approximately 20 competitors in the market for natural gas vehicle fuels in the U.S. and Canada, including:

We also face high levels of competition with respect to our other business activities. For instance, we compete with many third parties for the rights to procure RNG from producers and for customers to purchase the RNG that we sell. In addition, we transport and sell CNG through NG Advantage’s virtual natural gas pipelines and interconnects and compete with other participants in this market, including Xpress Natural Gas, Certarus, Thigpen, OsComp Systems and Irving Ltd.

We compete for vehicle fuel users based on demand for the type of fuel, which may be affected by a variety of factors, including, among others, cost, supply, availability, quality, cleanliness and safety of the fuel; cost, availability and reputation of vehicles and engines; convenience and accessibility of fueling stations; and recognition of the brand. We believe we compare favorably with our competitors on the basis of these factors; however, some of our competitors have substantially greater financial, marketing and other resources than we have. As a result, these competitors may be able to respond more quickly to changes in customer preferences, legal requirements or other industry or regulatory trends; devote greater resources to the development, promotion and sale of their products; adopt more aggressive pricing policies, dedicate more effort to infrastructure and systems development in support of their business or product development activities; implement more robust or creative initiatives to advance consumer acceptance of their products; or exert more influence on the regulatory landscape that impacts the vehicle fuels market.

We expect competition to increase in the vehicle fuels markets generally. In addition, if the demand for natural gas vehicle fuel increases, then we expect competition in the market for natural gas vehicle fuel would also increase.

Government Regulation and Environmental Matters

We are subject to a variety of federal, state and local laws and regulations relating to the environment, health and safety, labor and employment, building codes and construction, zoning and land use, the government procurement process,

any political activities or lobbying in which we may engage, public reporting and taxation, among others. Many of these laws and regulations are complex, change frequently and have become more stringent over time. Any changes to existing regulations, adoption of new regulations or failure by us to comply with applicable regulations may result in significant additional expense to us or our customers or a variety of administrative, civil and criminal enforcement measures, any of which could have a material adverse effect on our business, reputation, financial condition and results of operations. Regulations that significantly affect our various operating activities are described below. Compliance with these regulations has not had a material effect on our capital expenditures, earnings or competitive position to date, but new regulations or amendments to existing regulations to make them more stringent could have such an effect in the future. We cannot estimate the expenses we may incur to comply with potential new laws or changes to existing laws, or the other potential effects these laws may have on our business, and these unknown costs and effects are not specifically contemplated by our existing customer agreements or our budgets and cost estimates.

Construction and Operation of CNG and LNG Stations. To construct a CNG or LNG fueling station, we must satisfy permitting and other requirements and either we or a third-party contractor must be licensed as a general engineering contractor. Each CNG and LNG fueling station must be constructed in accordance with federal, state and local regulations pertaining to station design, environmental health, accidental release prevention, above-ground storage tanks and hazardous waste and other materials. For fueling stations we operate, we are also required to register with certain state agencies as a retailer/wholesaler of CNG and LNG. We also may benefit from any grant programs or similar government incentives that may be available for the construction of natural gas fueling stations.

Transfer of LNG. Federal safety standards require each transfer of LNG to be conducted in accordance with specific written safety procedures. These procedures must require that qualified personnel be in attendance during all LNG transfer operations, and these procedures must be implemented, and copies of the procedures must be available or displayed, at each LNG transfer location.

Construction and Operation of LNG Liquefaction Plants. To build and operate LNG liquefaction plants, we must apply for facility permits or licenses that address many aspects of plant operations, including storm water and wastewater discharges, waste handling and air emissions related to production activities and equipment operation. The construction of LNG plants must also be approved by local planning boards and fire departments.

Vehicle Finance. State agencies generally require the registration of finance lenders. For example, in California, pursuant to the California Finance Lenders Law, one of our subsidiaries is required to be registered as a finance lender with the California Department of Corporations.

Generation and Sale of RIN Credits and LCFS Credits. In February 2010, the EPA finalized the RFS (which was established by the Energy Policy Act of 1992/2005), which creates RINs that can be generated by the production and use of RNG in the transportation sector and sold to fuel providers that are not compliant under the RFS. In addition, CARB and comparable agencies in Oregon have adopted the Low Carbon Fuel Standard, which encourages low carbon “compliant” transportation fuels (including CNG, LNG and RNG) in the California and Oregon marketplace by allowing producers of these fuels to generate LCFS Credits that can be sold to noncompliant regulated parties.

Sale of Natural Gas Vehicle Fuel: AFTC. Under separate pieces of U.S. federal legislation, we have been eligible to receive the AFTC, an alternative fuels tax credit, for our natural gas vehicle fuel sales made between October 1, 2006 and December 31, 2019, and are eligible to receive AFTC for our natural gas vehicle fuel sales made during the year ending December 31, 2020. The AFTC credit is equal to $0.50 per gasoline gallon equivalent of CNG that we sold as vehicle fuel, and $0.50 per diesel gallon equivalent of LNG that we sold as vehicle fuel in 2017, 2018 and 2019, and sell in 2020. Based on the service relationship with our customers, either we or our customers claim the credit. On February 9, 2018, AFTC was retroactively extended from January 1, 2017 to December 31, 2017, and AFTC revenue for the 2017 calendar year was recognized and collected in 2018. On December 20, 2019, AFTC was retroactively extended beginning January 1, 2018 through December 31, 2020. AFTC revenue for 2018 and 2019 was recognized in 2019. AFTC may not be reinstated for vehicle fuel sales after December 31, 2020.

Sale of Natural Gas Vehicle Fuel, Operation of Fueling Stations and Production of LNG: Greenhouse Gas Emissions Regulation. California has enacted laws and regulations that require specified greenhouse gas emissions reductions, and

the federal government and several other state governments are considering similar measures. These regulations, if and when adopted and implemented, could affect several areas of our operations, including our sales of conventional and renewable natural gas and the operation of our CNG and LNG fueling stations and our LNG production plants.

California’s emissions laws require statewide reductions of greenhouse gas emissions to 1990 levels by 2020, 40% below 1990 levels by 2030, and 80% below 1990 levels by 2050. As of January 1, 2015, California’s AB 32 law began regulating the greenhouse gas emissions from transportation fuels, including the emissions associated with the CNG and LNG vehicle fuel we sell in the state.

Under AB 32, the regulated party with respect to CNG vehicle fuel use is the utility that owns the pipe through which the fossil fuel natural gas is sold. We anticipate that, over time, as the utilities’ costs increase to comply with this law, we or, to the extent we pass these costs through to our customers, our CNG customers will be required to pay more for CNG vehicle fuel to cover the increased AB 32 compliance costs of the utility. The amount of these costs that we or our CNG customers will be required to pay will be determined by the amount a utility spends to buy any carbon credits needed to comply with AB 32 and the amount of natural gas we or our customers buy through the utility’s pipeline. With respect to LNG vehicle fuel use, the LNG vehicle fuel provider is the regulated party under AB 32. As a result, we will incur increased costs to comply with AB 32, and the amount of the increase will be based on how much LNG vehicle fuel we sell that is regulated, CARB’s requirements relating to the regulation of LNG vehicle fuel, any applicable regulatory changes and the cost of any carbon credits we purchase to comply with AB 32. We expect to try to pass the costs we incur to comply with this law through to our LNG customers. To the extent we are not able to pass the increased costs of CNG and LNG vehicle fuel as a result of AB 32 through to our customers, we could experience increased direct expenses and reduced margins.

Sales and Marketing

We market our brands, products and services primarily through our direct sales force, which includes sales representatives covering all of our major geographic and customer markets, as well as attendance at trade shows and participation in industry conferences and events. Our sales and marketing team also works closely with federal, state and local government agencies to provide education about the value of natural gas as a vehicle fuel and to keep abreast of proposed and newly adopted regulations that affect our industry.

Employees

As of December 31, 2019, we employed 412 people. We have not experienced any work stoppages and none of our employees is subject to collective bargaining agreements. We believe our employee relations are good.

Seasonality

To some extent, our business may experience seasonality. For more information, see the discussion under “Seasonality and Inflation” in Item 7. Management’s Discussion and Analysis of Financial Condition and Results of Operations.

Intellectual Property

Our intellectual property rights primarily consist of trade secrets, know-how and trademarks, and we rely on a combination of trademark laws, trade secret laws, confidentiality provisions and other contractual provisions to protect these rights and our proprietary information. These intellectual property rights help us to retain existing business and secure new relationships with customers.

Corporate Information

We were incorporated under the laws of the State of Delaware in 2001. We have completed, and we anticipate continuing to pursue, acquisitions, investments, divestitures, joint ventures and other partnerships as we become aware of opportunities that we believe can increase our competitive advantages, expand our product offerings, take advantage of

industry developments and trends, enhance our market position or provide other benefits, including streamlining operations and reducing our costs. Recent significant transactions of this nature include the BP Transaction and the CEC Combination.

More Information

Our website is located at www.cleanenergyfuels.com. We make available, free of charge on our website, our annual reports on Form 10‑K, quarterly reports on Form 10‑Q, current reports on Form 8‑K and amendments to those reports filed or furnished pursuant to Section 13(a) or 15(d) of the Exchange Act as soon as reasonably practicable after we electronically file such material with, or furnish it to, the SEC. The SEC maintains a website at www.sec.gov that contains reports, proxy and information statements and other information regarding issuers that file electronically with the SEC, including us.

All references to our website in this report are inactive textual references and the contents of our website are not incorporated into this report.

Item 1A. Risk Factors

An investment in our Company involves a high degree of risk of loss. You should carefully consider the risk factors discussed below and all of the other information included in this report before you make any investment decision regarding our securities. We believe the risks and uncertainties described below are the most significant we face, but additional risks and uncertainties not known to us or that we currently deem immaterial could also be or become significant. The occurrence of any of these risks could harm our business, financial condition, results of operations, prospects and reputation and could cause the trading price of our common stock to decline.

Risks Related to Our Business

Our success is dependent on the willingness of fleets and other consumers to adopt natural gas as a vehicle fuel, which may not occur in a timely manner, at expected levels or at all.

Our success is highly dependent on the adoption by fleets and other consumers of natural gas as a vehicle fuel. The market for natural gas as a vehicle fuel has experienced slow, volatile and unpredictable growth in many sectors. For example, adoption and deployment of natural gas vehicles, both in general and in certain of our key customer markets, including heavy-duty trucking, have been slower and more limited than we anticipated. Also, other important fleet markets, including airports, refuse and public transit, had slower volume and customer growth in 2018 and 2019 that may continue. Moreover, adoption of and demand for the different types of natural gas vehicle fuel, including CNG, LNG and RNG (which can be delivered in the form of CNG or LNG), are subject to significant risks, including decreased LNG volumes in some markets in recent periods that may continue and may not be sufficiently offset by any increase in demand for RNG or CNG. If the market for natural gas as a vehicle fuel does not develop at improved rates or levels, or if a market develops but we are not able to capture a significant share of the market or the market subsequently declines, our business, prospects, financial condition and operating results would be harmed.

Factors that may influence the adoption of natural gas as a vehicle fuel, many of which are beyond our control, include, among others:

We are dependent on the production of natural gas vehicles and engines in our key customer and geographic markets by vehicle and engine manufacturers, over which we have no control.

Natural gas vehicle and engine manufacturers control the development, production, quality assurance, cost and sales and marketing of their products, which shapes the performance, availability and reputation of these products in the marketplace. Although we are dependent on these manufacturers to succeed in our target markets, we have no influence over their activities. For example, Cummins Westport is the only natural gas engine manufacturer for the heavy-duty truck market in the United States, and this and other original equipment manufacturers currently produce a relatively small number of natural gas engines and vehicles for the U.S. and Canadian markets. These manufacturers may not decide to expand or maintain, or may decide to discontinue or curtail, their natural gas engine or vehicle product lines. The limited production of natural gas engines and vehicles increases their cost and limits availability, which restricts large-scale adoption, and may reduce resale value, which may contribute to operator reluctance to convert their vehicles to natural gas. In addition, some operators have communicated to us that the first generation models of natural gas engines for heavy-duty trucks have a reputation for unsatisfactory performance, and that this reputation or their first-hand experiences of such performance may be a factor in operator decisions regarding whether or not to convert their fleets to natural gas. The success of our business strategies and initiatives depends on sufficient availability and adoption of high-performing natural gas vehicles, and as a result, any production failures by the third-party manufacturers of these vehicles or their engines could harm our results of operations, business and prospects.

If there are improvements in or perceived advantages of non-natural gas vehicle fuels or engines powered by these fuels, demand for natural gas vehicles may decline.

Use of electric heavy-duty trucks, buses and refuse trucks, which are key customer markets for our business, or the perception that electric vehicles providing satisfactory performance at an acceptable cost may soon be widely available for these or other applications, could reduce demand for natural gas vehicles generally and in these key markets. In addition, hydrogen, renewable diesel and other alternative fuels in development may prove to be, or may be perceived to be, cleaner, more cost-effective, more readily available or otherwise more beneficial alternatives to gasoline and diesel than conventional or renewable natural gas. Further, technological advances in the production, delivery and use of gasoline, diesel or other alternative vehicle fuels, or the failure of natural gas vehicle fuel technology to advance at an equal pace, could slow or limit adoption of natural gas vehicles. For example, advances in gasoline and diesel engine technology, including efficiency improvements and further development of hybrid engines, may offer a more cost-effective way for operators to use a cleaner vehicle fuel, which could reduce the likelihood that fleet customers purchase natural gas vehicles or convert their existing vehicles to natural gas. If any of these risks occur, our industry, prospects and results could materially suffer.

We have a history of losses and may incur additional losses in the future.

We incurred pre-tax losses in 2017 and 2018. During 2018 and 2019, our results were positively affected by $26.7 million and $47.1 million of AFTC revenue, respectively.  We may incur losses in future periods and we may never sustain profitability, either of which would adversely affect our business, prospects and financial condition and may cause the price of our common stock to fall. In addition, to try to achieve or sustain profitability, we may choose or be forced to take actions that result in material costs or material asset or goodwill impairments. For instance, in the third and fourth quarters of 2017, we recorded significant charges in connection with our former natural gas fueling compressor manufacturing business (which we subsequently combined with another company’s natural gas fueling compressor manufacturing business in the CEC Combination), our closure of certain fueling stations, our determination that certain assets were impaired as a result of the foregoing, and other actions. We review our assets for impairment whenever events or changes in circumstances indicate that the carrying value of an asset or asset group may not be recoverable and we perform a goodwill impairment test on an annual basis and between annual tests in certain circumstances, in each case in accordance with applicable accounting guidance and as described in the financial statements and related notes included in this report. Changes to the use of our assets, divestitures, changes to the structure of our business, significant negative industry or economic trends, disruptions to our operations, inability to effectively integrate any acquired businesses, further market capitalization declines, or other similar actions or conditions could result in additional asset impairment or goodwill impairment charges or other adverse consequences, any of which could have material negative effects on our financial condition, our results of operations and the trading price of our common stock.

Our business is influenced by environmental, tax and other government regulations, programs and incentives that promote natural gas or other alternatives as a vehicle fuel, and their adoption, modification or repeal could negatively affect our business.

Our business is influenced by federal, state and local tax credits, rebates, grants and other government programs and incentives that promote the use of RNG, CNG and LNG as a vehicle fuel. These include various government programs that make grant funds available for the purchase of natural gas vehicles and construction of natural gas fueling stations, as well as the AFTC tax credit under which we generate revenue for our natural gas vehicle fuel sales made through the end of 2020 but which may not be available for vehicle fuel sales made after December 31, 2020, particularly if other legislative priorities result in insufficient focus on this program during upcoming congressional sessions. Additionally, our business is influenced by laws, rules and regulations that require reductions in carbon emissions and/or the use of renewable fuels, such as the programs under which we generate RINs and LCFS Credits by selling RNG, CNG and LNG as a vehicle fuel.

These programs and regulations, which have the effect of encouraging the use of RNG, CNG or LNG as a vehicle fuel, could expire or be repealed or amended for a variety of reasons. For example, parties with an interest in gasoline and diesel, electric or other alternative vehicles or vehicle fuels, including lawmakers, regulators, policymakers, environmental or advocacy organizations or other powerful groups, may invest significant time and money in efforts to delay, repeal or otherwise negatively influence regulations and programs that promote natural gas. Many of these parties have substantially greater resources and influence than we have. Further, changes in federal, state or local political, social or economic conditions, including a lack of legislative focus on these programs and regulations, could result in their modification, delayed adoption or repeal. Any failure to adopt, delay in implementing, expiration, repeal or modification of these

programs and regulations, or the adoption of any programs or regulations that encourage the use of other alternative fuels or alternative vehicles over natural gas, would reduce the market for natural gas as a vehicle fuel and harm our operating results, liquidity and financial condition. For instance, California lawmakers and regulators have implemented various measures designed to increase the use of electric, hydrogen and other zero-emission vehicles, including establishing firm goals for the number of these vehicles operating on state roads by specified dates and enacting various laws and other programs in support of these goals. Although the influence of these or similar measures on our business and natural gas vehicle adoption in general remains uncertain, a focus by these groups on zero-emission vehicles over vehicles operating on natural gas adversely affects the market for natural gas vehicles and our business prospects.

Our RNG business may not be successful.

Our RNG business consists of purchasing RNG from third-party producers, including BP, and reselling this RNG through our natural gas fueling infrastructure as Redeem, our RNG vehicle fuel.

The success of our RNG business depends on our ability to secure, on acceptable terms, a sufficient supply of RNG from BP and other third parties; to sell this RNG in adequate volumes and at prices that are attractive to customers and produce acceptable margins for us; and to sell, at favorable prices, credits we may generate under applicable federal or state programs from our sale of RNG as a vehicle fuel, including RINs and LCFS Credits. If we are not successful at one or more of these activities, our RNG business could fail and our performance and financial condition could be materially harmed.

Our ability to maintain an adequate supply of RNG is subject to risks affecting RNG production. Projects that produce pipeline-quality RNG often experience unpredictable production levels or other difficulties due to a variety of factors, including, among others, problems with equipment, severe weather, construction delays, technical difficulties, high operating costs, limited availability or unfavorable composition of collected feedstock gas, and plant shutdowns caused by upgrades, expansion or required maintenance. In addition, increasing demand for RNG will result in more robust competition for supplies of RNG, including from other vehicle fuel providers, gas utilities (which may have distinct advantages in accessing RNG supply including potential use of ratepayer funds to fund RNG purchases if approved by a utility’s regulatory commission) and other users and providers. If any of our RNG suppliers experience these or other difficulties in their RNG production processes, or if competition for RNG supply materially increases, then our supply of RNG and our ability to resell it as a vehicle fuel could be jeopardized.

Our ability to generate revenue from our sale of RNG or our generation and sale of RINs and LCFS Credits depends on a number of factors, including the markets for RNG as a vehicle fuel and for these credits. The market for RNG as a vehicle fuel is subject to the same fluctuations and unpredictability that affect the market for natural gas vehicle fuel generally, which is discussed elsewhere in these risk factors. The markets for RINs and LCFS Credits have been volatile and unpredictable in recent periods, and the prices for these credits have been subject to fluctuations, including lower market prices for RINs since June 2019 that may continue. For example, in 2019 market prices for RINs were as high as approximately $1.90 and as low as approximately $0.50. Additionally, the value of RINs and LCFS Credits, and consequently the revenue levels we may receive from our sale of these credits, may be adversely affected by changes to the federal and state programs under which these credits are generated and sold or other market conditions. Further, our ability to generate revenue from sales of these credits depends on our strict compliance with these federal and state programs, which are complex and can involve a significant degree of judgment. If the agencies that administer and enforce these programs disagree with our judgments, otherwise determine we are not in compliance, conduct reviews of our activities or make changes to the programs, then our ability to generate or sell these credits could be temporarily restricted pending completion of reviews or as a penalty, permanently limited or lost entirely, and we could also be subject to fines or other sanctions. Any of these outcomes could force us to purchase credits in the open market to cover any credits we have contracted to sell, retire credits we may have generated but not yet sold, reduce or eliminate a significant revenue stream or incur substantial additional and unplanned expenses. We experienced many of these effects in connection with the administrative review by the CARB of our generation of LCFS Credits in the third and fourth quarters of 2017, during which we were restricted from selling and transferring accumulated LCFS Credits, we were required to make cash payments to third parties to settle preexisting commitments to transfer LCFS Credits, and certain of our LCFS Credits were invalidated. See the discussion under “Key Trends—Our Performance” in the MD&A in this report for more information about this administrative review and its effects. Moreover, in the absence of programs that allow us to generate

and sell RINs and LCFS Credits or other federal and state programs that support the RNG vehicle fuel market, or if our customers are not willing to pay a premium for RNG, we may be unable to operate our RNG business profitably or at all. Any such failure of our RNG business could have a significant negative effect on our performance, cash position and prospects.

Increases, decreases and general volatility in oil, gasoline, diesel and natural gas prices could adversely affect our business.

Gasoline and diesel are today's most prevalent vehicle fuels. Prices for crude oil, which is the commodity used to make gasoline and diesel, have been low in recent years, due in part to over-production and increased supply without a corresponding increase in demand. If the prices of crude oil, gasoline and diesel continue to be low or decline further, or if the price of natural gas increases without corresponding increases in the prices of crude oil, gasoline and diesel, then market adoption of natural gas as a vehicle fuel could be slowed or limited. Further, any of these circumstances could decrease the market's perception of a need for alternative vehicle fuels generally, which could cause the prospects for and success of our industry and our business to materially suffer. In addition, under these pricing conditions, we may not be able to offer our customers an attractive price advantage for RNG, CNG and LNG and maintain an acceptable margin on our sales. Any such failure could result in an inability to attract new customers or a loss of demand from existing customers, or could directly and negatively affect our results of operations if we are forced to reduce the prices at which we sell natural gas to try to avoid such an effect. Conversely, if prices of gasoline and diesel increase or the price of natural gas decreases, we may not be able to capture a material portion of any increase in the demand for natural gas vehicle fuel that could result from favorable pricing conditions, due to increased competition from new entrants in the natural gas vehicle fuels market, expanded programs by existing competitors, or other factors.

Pricing conditions may also exacerbate the cost differential between natural gas vehicles and gasoline or diesel-powered vehicles, which may lead operators to delay or refrain from purchasing or converting to natural gas vehicles. Generally, natural gas vehicles cost more initially than gasoline or diesel-powered vehicles because the components needed for a vehicle to use natural gas add to the vehicle’s base cost. Operators then seek to recover the additional base cost over time through the lower cost to fuel a natural gas vehicle. Operators may, however, perceive an inability to timely recover these additional initial costs if RNG, CNG and LNG fuel are not available at prices sufficiently lower than gasoline and diesel. Such an outcome could decrease our potential customer base and harm our business prospects.

Additionally, the prices of natural gas, crude oil, gasoline and diesel have been volatile in recent years, and this volatility may continue. Factors that may cause this volatility to continue include, among others, changes in supply and availability of crude oil and natural gas, government regulations, inventory levels, consumer demand, price and availability of alternatives, weather conditions, negative publicity about crude oil or natural gas drilling, production or importing techniques and methods, economic, health and political conditions, transportation costs and the price of foreign imports. Fluctuations in natural gas prices affect the cost to us of the natural gas commodity. High natural gas prices adversely affect our operating margins when we cannot pass the increased costs through to our customers. Conversely, lower natural gas prices reduce our revenue when the commodity cost is passed through to our customers. As a result, continued fluctuations in natural gas prices could have a significant effect on our operating results.

We face increasing competition from a variety of businesses, many of which have far greater resources, experience, customer bases and brand awareness than we have, and we may not be able to compete effectively with these businesses.

The market for vehicle fuels is highly competitive. The biggest competition for RNG, CNG and LNG use as a vehicle fuel is gasoline and diesel because the vast majority of vehicles in our key markets are powered by these fuels. We also compete with suppliers of other alternative vehicle fuels, including renewable diesel, biodiesel and ethanol, as well as producers and fuelers of alternative vehicles, including hybrid, electric and hydrogen-powered vehicles. Additionally, our stations compete directly with other natural gas fueling stations and indirectly with electric vehicle charging stations and fueling stations for other vehicle fuels. We also face high levels of competition with respect to our other business activities, including our procurement and sale of RNG and our transport and sale of CNG through the virtual natural gas pipelines and interconnects of our subsidiary, NG Advantage.

A number of businesses are in the market for natural gas and other alternatives for use as vehicle fuel, including alternative vehicle and alternative fuel companies, refuse collectors, industrial gas companies, truck stop and fuel station owners, fuel providers, gas marketers, utilities and their affiliates and other organizations. If the alternative vehicle fuel market grows, then the number and type of participants in this market and their level of capital and other commitments to alternative vehicle fuel programs could increase. Many of our competitors have substantially greater experience, customer bases, brand awareness and financial, marketing and other resources than we have. As a result, these competitors may be able to respond more quickly to changes in customer preferences, legal requirements or other industry or regulatory trends; devote greater resources to the development, promotion and sale of their products; adopt more aggressive pricing policies; dedicate more effort to infrastructure and systems development in support of their business or product development activities; implement more robust or creative initiatives to advance consumer acceptance of their products; or exert more influence on the regulatory landscape that affects the vehicle fuels market.

We expect competition to increase in the vehicle fuels market generally. In addition, if the demand for natural gas vehicle fuel increases, then we expect competition in the market for natural gas vehicle fuel would also increase. Any such increased competition may reduce our customer base and revenue and may lead to increased pricing pressure, reduced operating margins and fewer expansion opportunities.

Our Zero Now heavy-duty truck financing initiative subjects us to material risks, and if this program is not successful, our financial results and business could be materially adversely affected.

One of our key strategic objectives is to fuel more natural gas heavy-duty trucks. As part of our efforts to achieve this goal, we have launched the Zero Now truck financing program, which is intended to facilitate and increase the deployment of natural gas heavy-duty trucks in the United States and encourage these operators to fuel their trucks at our stations. The Zero Now program is unique and complex and subjects us to a variety of risks. See the discussion under “Customer Markets-Trucking” in Part I, Item 1. Business of this report and Note 13 for information about the structure of the program and certain agreements we have established in connection with its launch.

The Zero Now program may not be successful for a variety of reasons, including continued slow or limited adoption of natural gas trucks by fleet operators or the occurrence of any of the other risks described in these risk factors. For example, some operators have communicated to us that their reluctance to convert to natural gas trucks stems from insufficient incentive to convert due to emissions regulations or other requirements, lack of demand for the conversion from customers and drivers, experiences or reputation of unsatisfactory performance by the first generation models of heavy-duty truck engines, actual or perceived insufficiencies in the financial incentives to convert, concern regarding the residual value of heavy-duty trucks and prioritization of other competing business concerns. If a sufficient number of truck operators do not participate in the Zero Now program, then it will not achieve its intended benefits and we will have expended substantial resources on an initiative that does not produce results.

In addition, the structure and terms of the program subject us to certain additional risks. For example, the term credit agreement we have established to implement the program permits us to incur substantial additional debt, and the related credit support agreement obligates us to make quarterly payments in amounts that will vary depending on the outstanding principal under the term credit agreement. These commitments are subject to, and will amplify, the risks associated with our outstanding indebtedness, which are discussed elsewhere in these risk factors. In addition, the amounts owed under the term credit agreement and the credit support agreement use LIBOR as a benchmark for establishing the rate at which interest accrues. In July 2017, the U.K.’s Financial Conduct Authority, which regulates LIBOR, announced that it intends to phase out LIBOR by the end of 2021. We intend to monitor the developments with respect to the potential discontinuance of LIBOR after 2021 and work with SG, our lender under the term credit agreement, in order to minimize the effect of such a discontinuance on our financial condition and results of operations; however, the actual effect of the anticipated discontinuance of LIBOR on us and the cost of this indebtedness remains uncertain. If SG has increased costs due to changes in LIBOR, we may experience potential increases in interest rates under the term credit agreement, which could adversely impact our interest expense, results of operations and cash flows. Further, the commodity swap arrangements we established with an affiliate of TOTAL and THUSA in connection with launching the program introduce additional risks related to volatility in crude oil prices. These arrangements are designed to protect us from fluctuations in the price of crude oil; however, we may be subject to payment obligations if truck operators participating in the program do not use all of the fuel volume covered by the arrangements and we are not able to fully and timely sell the excess fuel

volume to our other customers. Any obligation to make payments under our commodity swap arrangements would increase our operating expenses and decrease our available cash flow, and any efforts to sell additional gallons to our other customers to avoid such payment obligations could result in lower margins and revenues.

Moreover, even if the Zero Now program achieves its intended goal of facilitating growth in the U.S. heavy-duty truck market, such growth may not positively affect our results for a variety of reasons. For example, if trucks purchased or financed in the program do not meet the minimum fuel purchase obligations under the supply agreements with us for any reason, including an operator experiencing lower-than-anticipated fuel demand or failing to comply with payment obligations under the supply agreement, then the program would not result in the intended growth in our fuel sales volume and consequent increase in our revenues. Although we have built America’s Natural Gas Highway, or ANGH, our nationwide network of natural gas truck-friendly fueling stations, some operators may choose to fuel their natural gas vehicles elsewhere due to lack of convenient access, fuel prices or other factors. In that event, we would remain obligated to make payments under the debt agreements we have established in connection with the Zero Now program, which are based on the cost of the trucks purchased or financed in the program and not the amount of fuel volume we actually sell. As a result, we could become subject to significant payments under these debt agreements without a corresponding increase in revenues, in which case our performance and liquidity would be materially adversely affected.

We must effectively manage these risks to obtain the anticipated benefits from our Zero Now truck financing program and achieve our objective of fueling additional natural gas heavy-duty trucks. If we are not successful in meeting these objectives, our business, financial condition and operating results would be materially and adversely affected.

We may need to raise additional capital to continue to fund our business or repay our debt, which could have negative effects and may not be available when needed, on acceptable terms or at all.

We require capital to make principal and interest payments on our indebtedness, and to pay for capital expenditures (including NG Advantage's capital expenditures), our other operating expenses, and any mergers, acquisitions or strategic investments, transactions or relationships we may pursue. If we cannot fund any of these activities with capital on-hand or cash provided by our operations, we may seek to obtain additional capital from other sources, such as by selling assets or pursuing debt or equity financing.

Asset sales and equity or debt financing may not be available when needed, on terms favorable to us or at all. Any sale of our assets to generate cash proceeds may limit our operational capacity and could limit or eliminate any revenue streams or business plans that are dependent on the sold assets. Any issuances of our common stock or securities convertible into our common stock to raise capital would dilute the ownership interest of our existing stockholders. Any debt financing we may pursue could require us to make significant interest or other payments and to pledge some or all of our assets as security. In addition, higher levels of indebtedness could increase our risk of non-repayment, adversely affect our creditworthiness and amplify the other risks associated with our existing debt, which are discussed elsewhere in these risk factors. Further, we may incur substantial costs in pursuing any capital-raising transactions, including investment banking, legal and accounting fees. On the other hand, if we are unable to obtain capital in amounts sufficient to fund our obligations, expenses and strategic initiatives, we could be forced to suspend, delay or curtail our business plans or operating activities or could default on our contractual commitments. Any such outcome could negatively affect our business, performance, liquidity and prospects.

Compliance with greenhouse gas emissions regulations may prove costly and negatively affect our performance and financial condition.

California has enacted laws and regulations that require specified greenhouse gas emissions reductions, and the federal government and several other state governments are considering similar measures. These regulations could affect several areas of our operations, including our sales of conventional and renewable natural gas and the operation of our CNG and LNG fueling stations and our LNG production plants. For instance, California’s AB 32 law, which regulates greenhouse gas emissions from transportation fuels, including emissions associated with the CNG and LNG vehicle fuel we sell, imposes increased compliance costs on utilities, suppliers and/or users of CNG and LNG fuel. See the discussion under “Government Regulation and Environmental Matters - Sale of Natural Gas Vehicle Fuel, Operation of Fueling Stations

and Production of LNG: Greenhouse Gas Emissions Regulation” in Part I, Item 1. Business of this report for information about the implementation of AB 32.

The increased costs of CNG and LNG vehicle fuel as a result of AB 32 could diminish the attractiveness of these fuels for existing and prospective customers in California, which could reduce our customer base and fuel sales in one of our key geographic markets. Additionally, to the extent we are not able to pass these increased costs through to our customers, we could experience increased expenses and reduced margins. Any of these outcomes could cause our performance to suffer, impair our ability to fulfill customer contracts and reduce our cash available for other aspects of our business. Moreover, if similar laws or regulations are adopted and implemented by other states or by the federal government, or if existing laws are amended to make them more stringent, any compliance costs associated with the new or amended laws could amplify these effects. Further, any such new or more stringent laws or regulations could require us to undertake or incur significant additional capital expenditures or other costs to, among other things, buy emissions or other environmental credits or invest in costly new emissions prevention technologies. We cannot estimate the expenses we may incur to comply with potential new laws or changes to existing laws, or the other potential effects these laws may have on our business, and these unknown costs and effects are not contemplated by our existing customer agreements or our budgets and cost estimates.

In addition, any failure by us to comply with existing or any future emissions laws or regulations could result in monetary penalties or a variety of other administrative, civil and criminal enforcement measures, any of which could have a material adverse effect on our business, reputation, financial condition, liquidity and results of operations.

NG Advantage may not be successful.

NG Advantage’s business consists of transporting and selling CNG for non-vehicle purposes via virtual natural gas pipelines and interconnects. NG Advantage transports CNG to industrial and institutional energy users that do not have direct access to natural gas pipelines. NG Advantage also transports CNG between pipelines for customers that desire to take advantage of commodity price differences.  NG Advantage faces unique risks, including among others:

If NG Advantage fails to manage any of these risks, our business, financial condition, liquidity results of operations, prospects and reputation may be harmed.

Our station construction activities subject us to a number of business and operational risks.

As part of our business activities, we design and construct natural gas fueling stations that we either own and operate ourselves or sell to our customers. These activities require a significant amount of judgment in determining where to build and open fueling stations, including predictions about fuel demand that may not be accurate for any of the locations we target. As a result, we have built stations that we may not open for fueling operations and we may open stations that fail to generate the volume or profitability levels we anticipate, either or both of which could occur due to a lack of sufficient customer demand at the station locations or for other reasons. For any stations that are completed but unopened, we would have substantial investments in assets that do not produce revenue, and for any stations that are open and underperforming, we may decide to close the stations. We determined to close a number of underperforming stations in the third and fourth quarters of 2017 and recorded impairment charges in connection with these closures and other related actions, and any further station closures could result in substantial additional costs and non-cash asset impairments or other charges and could harm our reputation and reduce our potential customer base.

We also face a number of operational challenges in connection with our station design and construction activities. For example, we may not be able to identify suitable locations for the stations we or our customers seek to build. Additionally, even if preferred sites can be located, we may encounter land use or zoning difficulties, challenges obtaining and retaining required permits and approvals or local resistance, any of which could prevent us or our customers from building new stations on these sites or limit or restrict the use of new or existing stations. Any such difficulties, resistance or limitations or any failure to comply with local permit, land use or zoning requirements could restrict our activities or expose us to fines, reputational damage or other liabilities, which would harm our business and results of operations. In addition, we act as the general contractor and construction manager for new station construction and facility modification projects, and we typically rely on licensed subcontractors to perform the construction work. We may be liable for any damage we or our subcontractors cause or for injuries suffered by our employees or our subcontractors’ employees during the course of work on our projects. Additionally, shortages of skilled subcontractor labor could significantly delay a project or otherwise increase our costs. Further, our expected profit from a project is based in part on assumptions about the cost of the project, and cost overruns, delays or other execution issues may, in the case of projects we complete and sell to customers, result in our failure to achieve our expected margins or cover our costs, and in the case of projects we build and own, result in our failure to achieve an acceptable rate of return. If any of these events occur, our business, operating results and liquidity could be negatively affected.

We have significant contracts with government entities, which are subject to unique risks.

We have, and expect to continue to seek, long-term RNG, CNG and LNG station construction, maintenance and fuel sale contracts with various government bodies, which accounted for 19%, 22% and 21% of our revenue in 2017, 2018, and 2019, respectively. In addition to normal business risks, including the other risks discussed in these risk factors, our contracts with government entities are often subject to unique risks, some of which are beyond our control. For example, long-term government contracts and related orders are subject to cancellation if adequate appropriations for subsequent performance periods are not made. Further, the termination of funding for a government program supporting any of our government contracts could result in the loss of anticipated future revenue attributable to the contract. Moreover, government entities with which we contract are often able to modify, curtail or terminate contracts with us at their convenience and without prior notice, and would only be required to pay for work completed and commitments made at or prior to the time of termination.

In addition, government contracts are frequently awarded only after competitive bidding processes, which are often protracted. In many cases, unsuccessful bidders for government contracts are provided the opportunity to formally protest the contract awards through various agencies or other administrative and judicial channels. The protest process may substantially delay a successful bidder’s contract performance, result in cancellation of the contract award entirely and distract management. As a result, we may not be awarded contracts for which we bid, and substantial delays or cancellation of contracts may follow any successful bids as a result of any protests by other bidders. The occurrence of any of these risks would have a material adverse effect on our results of operations and financial condition.

Our operations entail inherent safety and environmental risks, which may result in substantial liability to us.

Our operations entail inherent safety risks, including risks associated with equipment defects, malfunctions, failures and misuses. For example, operation of LNG pumps requires special training because of the extremely low temperatures of LNG. Also, LNG tanker trailers and CNG fuel tanks and trailers could rupture if involved in accidents or improper maintenance or installation. Further, improper refueling of natural gas vehicles or operation of natural gas vehicle fueling stations could result in sudden releases of pressure that could cause explosions. In addition, our stations may vent methane, a potent greenhouse gas. These safety and environmental risks could result in uncontrollable flows of natural gas, fires, explosions, death or serious injury, any of which may expose us to liability for personal injury, wrongful death, property damage, pollution and other environmental damage. We may incur substantial liability and costs if any such damages are not covered by insurance or are in excess of policy limits, or if environmental damage causes us to violate applicable greenhouse gas emissions or other environmental laws. Additionally, the occurrence of any of these events with respect to our fueling stations or our other operations could materially harm our business and reputation. Moreover, the occurrence of any of these events to any other organization in the natural gas vehicle fuel business could harm our industry generally by negatively affecting perceptions about, and adoption levels of, natural gas as a vehicle fuel.

Our business is subject to a variety of government regulations, which may restrict our operations and result in costs and penalties.

We are subject to a variety of federal, state and local laws and regulations relating to the environment, health and safety, labor and employment, building codes and construction, zoning and land use, the government procurement process, any political activities or lobbying in which we may engage, public reporting and taxation, among others. It is difficult and costly to manage the requirements of every authority having jurisdiction over our various activities and to comply with their varying standards. Many of these laws and regulations are complex, change frequently, involve significant judgment and have become more stringent over time. Any changes to existing regulations or adoption of new regulations may result in significant additional expense to us or our customers. For example, some communities and cities, like Berkeley, CA, have banned new natural gas hook-ups. Further, from time to time, as part of the regular evaluation of our operations, including newly acquired or developing operations, we may be subject to compliance audits by regulatory authorities, which may distract management from our revenue-generating activities and involve significant costs and use of other resources. Also, we often need to obtain facility permits or licenses to address, among other things, storm water or wastewater discharges, waste handling and air emissions in connection with our operations, which may subject us to onerous or costly permitting conditions or delays if permits cannot be timely obtained.

Our failure to comply with any applicable laws and regulations could result in a variety of administrative, civil and criminal enforcement measures, including, among others, assessment of monetary penalties, imposition of corrective requirements or prohibition from providing services to government entities. If any of these enforcement measures were imposed on us, our business, financial condition and performance could be negatively affected.

We may from time to time pursue acquisitions, divestitures, investments or other strategic relationships or transactions, which could fail to meet expectations or otherwise harm our business.

We may acquire or invest in other companies or businesses or pursue other strategic transactions or relationships, such as joint ventures, collaborations, divestitures or other similar arrangements. For example, in March 2017 we completed the BP Transaction, in December 2017 we completed the CEC Combination, and in October 2018 and January 2019 we established arrangements with THUSA and others to launch the Zero Now truck financing program.

These strategic transactions and relationships and any others we may pursue in the future involve numerous risks, any of which could harm our business, performance and liquidity, including, among others:

Our results of operations fluctuate significantly and are difficult to predict.

Our results of operations have historically experienced, and may continue to experience, significant fluctuations as a result of a variety of factors, including, among others, the amount and timing of our natural gas vehicle fuel sales, station construction sales, sales of RINs and LCFS Credits and recognition of government credits, grants and incentives, such as AFTC (for example, we recorded all of the AFTC revenue associated with our vehicle fuel sales made in 2017 during the first quarter of 2018, and we recorded all of the AFTC revenue associated with our vehicles fuel sales made in 2018 and 2019 in the fourth quarter of 2019); fluctuations in commodity, station construction and labor costs and natural gas, RIN and LCFS Credit prices; variations in the fair value of certain of our derivative instruments that are recorded in revenue; the amount and timing of our billing, collections and liability payments; and the other factors described in these risk factors.

Our performance in certain periods has also been affected by transactions or events that have resulted in significant cash or non-cash gains or losses. For example, our results for 2017 were positively affected by gains related to repurchases or retirements of our outstanding convertible debt at a discount and by a gain related to the BP Transaction, but were also negatively affected by significant charges in connection with our closure of certain fueling stations, the decreased operating performance of our former natural gas fueling compressor manufacturing business, our determination of an impairment of assets as a result of the foregoing, and certain other actions. These or other similar gains or losses may not recur regularly, in the same amounts or at all in future periods.

These significant fluctuations in our operating results may render period-to-period comparisons less meaningful, and investors in our securities should not rely on the results of one period as an indicator of performance in any other period. Additionally, these fluctuations in our operating results could cause our performance in any period to fall below the

financial guidance we may have provided to the public or the estimates and projections of the investment community, which could negatively affect the price of our common stock.

We depend on key people to generate and oversee our strategies and operate our business, and our business could be harmed if we are unable to retain these key people.

We believe our future success is dependent on the contributions of certain key people, including our executive officers and directors. In many cases, we believe these individuals’ knowledge of our business and experience in our industry would be difficult to replace. As a result, and due to the high levels of competition for talent in our industry, we may incur significant costs to try to retain these key people. All of our employees, however, including our management team, are permitted to terminate their employment relationships with us at any time, and any of our directors could resign at any time or fail to be re-elected by our stockholders on an annual basis. If we are unable to retain our key people, or if these individuals leave our Company and we are unable to attract and successfully integrate quality replacements in a timely manner and on reasonable terms, our business, operating results and financial condition could be harmed.

Natural gas purchase and sale commitments may exceed demand or supply, as applicable, which could cause our costs relative to our revenue to increase.

We are a party to two long-term natural gas purchase agreements with a take-or-pay commitment, and we may enter into additional similar contracts in the future. These take-or-pay commitments require us to pay for the natural gas we have agreed to purchase, irrespective of whether we sell the gas. If the market for natural gas as a vehicle fuel declines or fails to develop as we anticipate, if we lose natural gas vehicle fueling customers, or if demand under any existing or future sales contract diminishes, these take-or-pay commitments may exceed our natural gas demand. In addition, we are involved in various firm commitment natural gas supply arrangements, and we may establish additional similar arrangements in the future. These arrangements require us to supply certain volumes of natural gas over specified periods of time, and subject us to deficiency payments or other penalties if we are unable to deliver the committed volumes as and when required. If we fail to generate sufficient demand for our take-or-pay purchase commitments or satisfy our firm supply commitments, our supply costs or operating expenses could increase without a corresponding increase in revenue, which could negatively affect our margins, performance and liquidity.

We provide financing to fleet customers for natural gas vehicles, which exposes our business to credit risks.

We directly lend to certain qualifying customers a portion, and occasionally all, of the purchase price of natural gas vehicles they agree to buy. This direct financing is in addition to our funding of the incremental cost of natural gas heavy-duty trucks purchased or leased in our Zero Now truck financing program. These financing activities involve a number of risks, including general credit risks associated with equipment finance relationships. For example, financed equipment often consists mostly of vehicles, which are mobile and easily damaged, lost or stolen. In addition, the borrower may default on payments, enter bankruptcy proceedings or liquidate. The materialization of any of these risks could harm our vehicle finance business and our results of operations and liquidity.

Our warranty reserves may not adequately cover our warranty obligations, which could result in unexpected costs.

We provide product warranties with varying terms and durations for the stations we build and sell, and we establish reserves for the estimated liability associated with these warranties. Our warranty reserves are based on historical trends and any specifically identified warranty issues known to us, and the amounts estimated for these reserves could differ materially from the warranty costs we may actually incur. We would be adversely affected by an increase in the rate or volume of warranty claims or the amounts involved in warranty claims, any of which could increase our costs beyond our established reserves and cause our cash position and financial condition to suffer.

We rely on information technology in our operations, and any material failure, inadequacy, interruption or security failure of that technology could harm our business.

Increased global IT security threats and more sophisticated and targeted computer crime pose a risk to the security of our systems and networks and the confidentiality, availability and integrity of our data. There have been several recent,

highly publicized cases in which organizations of various types and sizes have reported the unauthorized disclosure of customer or other confidential information, as well as cyberattacks involving the dissemination, theft and destruction of corporate information, intellectual property, cash or other valuable assets. There have also been several highly publicized cases in which hackers have requested “ransom” payments in exchange for not disclosing customer or other confidential information or for not disabling the target company’s computer or other systems. Implementing security measures designed to prevent, detect, mitigate or correct these or other IT security threats involves significant costs. Although we have taken steps to protect the security of our information systems and the data maintained in those systems, we have, from time to time, experienced threats to our data and systems, including malware and computer virus attacks and it is possible that in the future our safety and security measures will not prevent the systems’ improper functioning or damage, or the improper access or disclosure of personally identifiable information such as in the event of cyberattacks. Any IT security threats that are successful against our security measures could, depending on their nature and scope, lead to the compromise of confidential information, improper use of our systems and networks, manipulation and destruction of data, operational disruptions and substantial financial outlays. Further, a cyberattack could occur and persist for an extended period of time without detection, and an investigation of any successful cyberattack would likely require significant time, costs and other resources to complete. We may be required to expend significant financial resources to protect against or to remediate such cyberattacks. In addition, our technology infrastructure and information systems are vulnerable to damage or interruption from natural disasters, power loss and telecommunications failures. Any failure to maintain proper function, security and availability of our information systems and the data maintained in those systems could interrupt our operations, damage our reputation, subject us to liability claims or regulatory penalties, harm our business relationships or increase our security and insurance costs, which could have a material adverse effect on our business, financial condition and results of operations.

Global climate change may increase the frequency and severity of weather events and the losses resulting from these events, which could have a material adverse effect on our business and the markets in which we operate.

Over the past several years, changing weather patterns and climatic conditions have added to the unpredictability and frequency of natural disasters in certain parts of the world and have created additional uncertainty as to future trends. We cannot predict whether or to what extent natural disasters may occur or increase, nor can we predict the effect such events will have on our operations or the geographic markets in which we operate; however, any increased frequency or severity of these events could increase their overall negative effect on economic conditions in these regions and could also directly affect our operations if our fueling stations, our LNG plants or our customers’ operations are damaged or otherwise subjected to limited operations as a result of such an event. The occurrence of any of these risks could negatively affect our business, performance and liquidity, and could also cause the price of our common stock to decline.

We may not generate sufficient cash flow from our business to pay our debt.

We have material indebtedness, and we are permitted to incur significant additional debt under the agreements we established in connection with our Zero Now truck financing program. Our outstanding and permitted indebtedness could make us more vulnerable to adverse changes in general U.S. and worldwide economic, regulatory and competitive conditions, limit our flexibility to plan for or react to changes in our business or industry, place us at a disadvantage compared to our competitors that have less debt or limit our ability to borrow or otherwise raise additional capital as needed.

Our payments of amounts owed under our agreements related to our Zero Now program and various other debt instruments will reduce our cash resources available for other purposes, including pursuing strategic initiatives, transactions or other opportunities, satisfying our other commitments and generally supporting our operations. Moreover, our ability to make these payments depends on our future performance, which is subject to economic, financial, competitive and other factors, including those described in these risk factors, and many of which are beyond our control. Our business may not generate sufficient cash from operations to service our debt.

If we cannot meet our debt obligations from our operating cash flows, we may pursue one or more alternative measures. For instance, we are permitted to issue up to 14.0 million shares of our common stock to repay part of the outstanding principal amount of our outstanding convertible notes due June 2020. Any repayment of our debt with equity, however, would dilute the ownership interests of our existing stockholders. Additionally, because the agreements

governing much of our existing indebtedness contain minimal restrictions on our ability to incur additional debt and do not require us to maintain financial ratios or specified levels of net worth or liquidity, we may seek capital from other sources to service our debt, such as selling assets, restructuring or refinancing our existing debt or obtaining additional equity or debt financing. Our ability to engage in any of these activities, if we decide to do so, would depend on the capital markets and the state of our industry, business and financial condition at the time, and could also subject us to significant risks, which are discussed elsewhere in these risk factors. Moreover, we may not be able to obtain any additional capital we may pursue on desirable terms, at a desirable time or at all. Any failure to pay our debts when due could result in a default on our debt obligations. In addition, certain of our debt agreements contain restrictive covenants, and any failure by us to comply with these covenants could also cause us to be in default under these agreements.

In the event of any default on our debt obligations, the holders of the indebtedness could, among other things, declare all amounts owed immediately due and payable. Additionally, with respect to any amounts owed under our term credit agreement that are paid by THUSA pursuant to its guaranty rather than by us, THUSA would be permitted to take direct possession of funds paid by fleet operators under any fuel supply agreements we establish in connection with our Zero Now truck financing program. Any such declaration or possession of funds could deplete all or a large portion of our available cash flow, and thereby reduce the amount of cash available to pursue our business plans or force us into bankruptcy or liquidation.

Risks Related to Our Common Stock

A significant portion of our common stock is beneficially owned by a single stockholder that may have interests that differ from yours and that is able to exert significant influence over our corporate decisions, including a change of control.

Following our issuance and sale of our common stock to Total in June 2018, Total holds approximately 25% of our outstanding shares of common stock and the largest ownership position of our Company. In addition, TOTAL was granted certain special rights that our other stockholders do not have in connection with its acquisition of this ownership position, including the right to designate two individuals to serve as directors of our Company and a third individual to serve as an observer on certain of our board committees. TOTAL or other large stockholders may be able to influence or control matters requiring approval by our stockholders, including the election of directors and mergers, acquisitions or other extraordinary transactions. TOTAL, however, may have interests that differ from yours and may vote or otherwise act in ways with which you disagree or that may be adverse to your interests. A concentration of stock ownership may also have the effect of delaying, preventing or deterring a change of control of our Company, which could deprive our stockholders of an opportunity to receive a premium for their shares of our common stock as part of a sale of our Company and could affect the market price of our common stock. Conversely, such a concentration of stock ownership may facilitate a change of control under terms you and other stockholders may not find favorable or at a time when you and other stockholders may prefer not to sell.

Sales of our common stock, or the perception that such sales may occur, could cause the market price of our stock to drop significantly, regardless of the state of our business.

All outstanding shares of our common stock are eligible for sale in the public market, subject in certain cases to the requirements of Rule 144 under the Securities Act. Also, shares of our common stock that may be issued upon the exercise, vesting or conversion of our outstanding stock options, restricted stock units and convertible notes may be eligible for sale in the public market, to the extent permitted by Rule 144 and the provisions of the applicable stock option, restricted stock unit and convertible note agreements or if such shares have been registered under the Securities Act. For instance, we filed a registration statement with the SEC to cover the resale of the 50,856,296 shares of our common stock issued and sold to Total, which such registration statement was declared effect in August 2018. We have also registered for resale all shares of our common stock issuable upon conversion of the 7.5% notes originally issued to T. Boone Pickens and Green Energy Investment Holdings, LLC in June 2013. See Note 13 for additional information. If these shares are sold, or if it is perceived that they may be sold, in the public market, the trading price of our common stock could decline.

The price of our common stock may continue to fluctuate significantly, and you could lose all or part of your investment.

The market price of our common stock has experienced, and may continue to experience, significant volatility. Factors that may cause volatility in the price of our common stock, many of which are beyond our control, include, among others:

In addition, the securities markets have from time to time experienced significant price and volume fluctuations that are unrelated to the operating performance of particular companies, but which have affected the market prices of these companies’ securities. These market fluctuations may also materially and adversely affect the market price of our common stock.

Volatility or declines in the market price of our common stock could have other negative consequences, including, among others, further impairments to our assets (following the asset impairment charges we recorded in the third and fourth quarters of 2017 related to our former natural gas fueling compressor manufacturing business and our closure of certain fueling stations), potential impairments to our goodwill and a reduced ability to use our common stock for capital-raising, acquisitions or other purposes. The occurrence of any of these risks could materially and adversely affect our financial condition, results of operations and liquidity and could cause further declines in the market price of our common stock.

Item 1B.   Unresolved Staff Comments.

None.

Item 2.   Properties.

Our corporate headquarters are located at 4675 MacArthur Court, Suite 800, Newport Beach, California 92660, where we occupy approximately 48,000 square feet of office space. Our lease for this facility expires in June 2021.

We own and operate the Boron Plant in Boron, California, approximately 125 miles from Los Angeles. In November 2006, we entered into a 30-year ground lease for the 36 acres on which this plant is situated.

We own and operate the Pickens Plant located in Willis, Texas, approximately 50 miles north of Houston. We own approximately 24 acres of land on which this plant is situated, along with approximately 34 acres surrounding the plant.

Item 3.   Legal Proceedings.

From time to time, we may become involved in various legal proceedings that arise in the ordinary course of our business, including lawsuits, claims, audits, government enforcement actions and related matters. It is not possible to predict when or if these proceedings may arise, nor is it possible to predict the outcome of any proceedings that do arise, including, among other things, the amount or timing of any liabilities we may incur, and any such proceedings could have a material effect on us regardless of outcome. In the opinion of management, however, we are not a party, and our properties are not subject, to any pending legal proceedings that are material to us.

Item 4.   Mine Safety Disclosures.

None.

PART II

Item 5.   Market for Registrant’s Common Equity, Related Stockholder Matters and Issuer Purchases of Equity Securities.

Market Information

Our common stock trades on The Nasdaq Global Select Market under the symbol “CLNE.”

Holders

There were approximately 53 holders of record of our common stock as of March 4, 2020.

Performance Graph

This performance graph shall not be deemed “soliciting material” or “filed” with the SEC or subject to Regulation 14A or 14C or to the liabilities of Section 18 of the Exchange Act, or incorporated by reference into any filing under the Securities Act or the Exchange Act, except to the extent that we specifically request that such information be treated as soliciting material or specifically incorporate it by reference into such a filing. The graph is required by applicable rules of the SEC and is not intended to forecast, predict or be indicative of the possible future performance of our common stock.

The following graph compares the five-year total return to holders of our common stock relative to the cumulative total returns of the Nasdaq Global Market Index and the Russell 2000 Index. The graph assumes that $100 was invested in our common stock and on each of these indices at the close of market on December 31, 2014 (the last trading day before the beginning of our fifth preceding fiscal year). We chose to include the Russell 2000 Index because it includes issuers with similar market capitalizations as us and due to the lack of a comparable industry or line-of-business index or peer

group, as we are the only actively traded public company whose only line of business is to sell natural gas for use as a vehicle fuel and the associated equipment and services necessary to use natural gas as a vehicle fuel.

Item 6.   Selected Financial Data.

The following selected historical consolidated financial data should be read together with Item 7. Management’s Discussion and Analysis of Financial Condition and Results of Operations and our consolidated financial statements and the related notes included in this report, which describe, among other things, factors that could materially affect the comparability of the data reflected below. Additionally, see Item 1A. Risk Factors and Item 7. Management’s Discussion and Analysis of Financial Condition and Results of Operations for discussions of material uncertainties that might cause the data reflected below not to be indicative of our future financial condition or results of operations.

The consolidated statements of operations data for the years ended December 31, 2017, 2018 and 2019 and the consolidated balance sheet data as of December 31, 2018 and 2019 are derived from our audited consolidated financial statements included in this report. The consolidated statements of operations data for the years ended December 31, 2015 and 2016 and the consolidated balance sheet data as of December 31, 2015, 2016 and 2017 are derived from our audited consolidated financial statements that are not included in this report.

During the year ended December 31, 2017, we sold certain assets to BP in the BP Transaction, and combined our natural gas compressor subsidiary, CEC, with the natural gas compressor subsidiaries of Landi Renzno S.p.A., in a new company known as “SAFE&CEC S.r.l.” (referred to as the “CEC Combination”). In addition, the results of the divested companies are included in our consolidated financial statements prior to their respective dates of divestiture. The

consolidated balance sheet data as of December 31, 2019 reflects the modified retrospective transition method adoption of Accounting Standards Update (“ASU”) 2016-02, Leases (842).

Item 7.   Management’s Discussion and Analysis of Financial Condition and Results of Operations.

The following Management’s Discussion and Analysis of Financial Condition and Results of Operations (this discussion, as well as discussions under the same heading in our other periodic reports, are referred to as the “MD&A”) should be read together with our audited consolidated financial statements and the related notes included in this report, and all cross references to notes included in this MD&A refer to the identified note in such consolidated financial statements. This section of the Form 10-K generally discusses 2019 and 2018 items and year-to-year comparisons of 2019 to 2018. Discussions of 2017 items and year-to-year comparisons of 2018 and 2017 that are not included in this Form 10-K can be found in “Management’s Discussion and Analysis of Financial Condition and Results of Operations” in Part II, Item 7 of our Annual Report on Form 10-K for the year ended December 31, 2018, filed with the SEC on March 12, 2019.

Cautionary Note Regarding Forward-Looking Statements

This MD&A contains forward-looking statements. See the discussion about these statements under “Cautionary Note Regarding Forward-Looking Statements” at the beginning of this report.

Overview

We are North America’s leading provider of the cleanest fuel for the transportation market, based on the number of stations operated and the amount of gasoline gallon equivalents (“GGEs”) of RNG, CNG and LNG delivered. Through our sales of Redeem™ RNG, which is derived from biogenic methane produced by the breakdown of organic waste, we 

help thousands of vehicles, from airport shuttles to city buses to waste and heavy-duty trucks, to reduce their amount of climate-harming greenhouse gas by at least 70% and up to 300% depending on the source of the RNG feedstock.  Redeem is delivered through compressed natural gas (CNG) and liquefied natural gas (LNG); sales of our Redeem RNG have increased dramatically, from 13.0 million GGEs in 2013 (the year we introduced Redeem RNG to the vehicle fuel market) to 143.3 million GGEs in 2019.

Our principal business is supplying RNG, CNG and LNG for medium and heavy-duty vehicles and providing O&M services for public and private vehicle fleet customer stations. As a comprehensive solution provider, we also design, build, operate and maintain fueling stations; sell and service natural gas fueling compressors and other equipment used in CNG stations and LNG stations; offer assessment, design and modification solutions to provide operators with code-compliant service and maintenance facilities for natural gas vehicle fleets; transport and sell CNG and LNG via “virtual” natural gas pipelines and interconnects; procure and sell RNG; sell tradable credits we generate by selling RNG and conventional natural gas as a vehicle fuel, including RIN Credits and LCFS Credits; help our customers acquire and finance natural gas vehicles; and obtain federal, state and local tax credits, grants and incentives. In addition, before March 31, 2017, we produced RNG at our own production facilities (which we sold, along with certain of our other RNG production assets, in the BP Transaction), and before December 29, 2017, we manufactured natural gas fueling compressors and other equipment used in CNG stations (which we combined with another company’s natural gas fueling compressor manufacturing business in a newly formed joint venture, in the CEC Combination).

We serve fleet vehicle operators in a variety of markets, including heavy-duty trucking, airports, refuse, public transit, industrial and institutional energy users, and government fleets. We believe these fleet markets will continue to present a growth opportunity for natural gas vehicle fuel for the foreseeable future. As of December 31, 2019, we serve over 1,000 fleet customers operating over 48,000 natural gas vehicles, and we own, operate or supply approximately 550 natural gas fueling stations in 41 states in the United States and four provinces in Canada.

Performance Overview

This performance overview discusses matters on which our management focuses in evaluating our financial condition and operating results.

Sources of Revenue

The following table represents our sources of revenue:

Key Operating Data

In evaluating our operating performance, our management focuses primarily on: (1) the amount of RNG, CNG and LNG gasoline gallon equivalents delivered (which we define as (i) the volume of gasoline gallon equivalents we sell to our customers as fuel, plus (ii) the volume of gasoline gallon equivalents dispensed at facilities we do not own but where we provide O&M services on a per-gallon or fixed fee basis, plus (iii) our proportionate share of the gasoline gallon equivalents sold as CNG by our joint venture with Mansfield Ventures, LLC called Mansfield Clean Energy Partners, LLC (“MCEP”), plus (iv) for periods before completion of the BP Transaction, our proportionate share (as applicable) of the gasoline gallon equivalents of RNG produced and sold as pipeline quality natural gas by our former RNG production facilities, which we sold in the BP Transaction), (2) our station construction cost of sales, (3) our gross margin (which we define as revenue minus cost of sales), and (4) net income (loss) attributable to us. The following tables present our key operating data for the years ended December 31, 2017, 2018, and 2019:

RNG sold as vehicle fuel under the brand name RedeemTM is included in the CNG or LNG amounts in the table above as applicable based on the form in which it was sold. GGEs of Redeem sold for the years ended December 31, 2017, 2018 and 2019 were as follows:

2018 -2020 Developments

Zero Now Truck Financing Program. We launched the Zero Now truck financing program, which is intended to facilitate and increase the deployment of commercially available ultra-low NOx natural gas heavy-duty trucks in the United States and encourage these operators to fuel their trucks at our stations. The Zero Now program is unique and complex, and has involved our entry into various arrangements in order to launch the program, including a term credit agreement for delayed draw loans of up to $100.0 million; a credit support agreement with THUSA, a wholly owned subsidiary of TOTAL, under which THUSA has guaranteed our obligations under the term credit agreement in exchange for a quarterly fee; and commodity swap arrangements with an affiliate of THUSA and TOTAL covering five million diesel gallons of natural gas fuel volume annually from April 2019 through June 2024, which are intended to manage diesel price fluctuation risks related to the natural gas fuel supply commitments we expect to make in our anticipated fueling agreements with fleet operators that participate in the Zero Now program. See the disclosure under “Customer Markets-Zero Now” in “Item 1. Business” of this report for information about these agreements and the structure of the program.

Debt Repurchase. In December 2018, we purchased from the holders thereof all outstanding 7.5% Convertible Notes due July 2019, having an aggregate outstanding principal amount of $50.0 million, for a cash purchase price of $50.5 million. Upon such purchase, all such notes were surrendered and canceled in full and we have no further obligations under these notes. As a result of the early retirement of these notes we saved $1.7 million in interest expense in 2019. See Note 13 for more information about our outstanding debt.

Expanded BP RNG Supply Agreement. In October 2018, our supply agreement with BP was amended to extend the term and add additional RNG supply. We share with BP in the RINs and LCFS Credits generated from the increased RNG supply sold through our vehicle fueling infrastructure and to other customers.

Full Cash Repayment of 5.25% Notes. On October 1, 2018, we paid to the holders of our 5.25% Convertible Senior Notes due October 2018, in cash, all amounts then owed under the notes, totaling an aggregate of $110.5 million in principal amount plus $2.9 million in accrued and unpaid interest. Upon such payment, all such notes were surrendered and canceled in full and we have no further obligations under these notes.

Total Private Placement. On May 9, 2018, we entered into a stock purchase agreement with Total Marketing Services, S.A. (“Total”), a wholly owned subsidiary of TOTAL, for the sale and issuance to Total of up to 50,856,296 shares of our common stock for a per share purchase price of $1.64 and an aggregate purchase price of $83.4 million, all in a private placement (the “Total Private Placement”). The Total Private Placement closed on June 13, 2018, upon the satisfaction of all conditions to closing. We used the net proceeds from the Total Private Placement for working capital and general corporate purposes, which included retiring a portion of our outstanding indebtedness.

The agreements related to the Total Private Placement also contain representations, warranties and covenants made by us and Total regarding, among other matters, certain director designation rights we have granted to Total (along with undertakings by certain of our stockholders, including all of our directors and executive officers, to vote their shares in favor of such director designees in future elections of directors), certain registration rights we have granted to Total for the shares that were issued and sold, certain limitations on Total’s purchase of additional securities of our Company without the approval of our board of directors, and various other matters that are customary for transactions of this nature.

AFTC. The AFTC, which had previously expired on December 31, 2016, was reinstated on February 9, 2018 to apply to vehicle fuel sales made from January 1, 2017 through December 31, 2017. As a result, all AFTC revenue for vehicle fuel we sold in the 2017 calendar year, which totaled $25.2 million, was recognized and collected during the year ended December 31, 2018. In addition, during the year ended December 31, 2018, the Internal Revenue Service approved, and we recognized as revenue, $1.5 million of AFTC credit claims related to prior years. On December 20, 2019, AFTC was retroactively extended beginning January 1, 2018 through December 31, 2020. As a result, AFTC revenue for vehicle fuel we sold in 2018 and 2019, which totaled $47.1 million, was recognized during the year ended December 31, 2019. The AFTC credit for 2017, 2018 and 2019 was equal to $0.50 per gasoline gallon equivalent of CNG that we sold as vehicle fuel, and $0.50 per diesel gallon of LNG that we sold as vehicle fuel. AFTC is currently available through December 31, 2020 and may not be reinstated for vehicle fuel sales made after that date.

NG Advantage. During the year ended December 31, 2019, we loaned to our subsidiary NG Advantage, LLC (“NG Advantage”) an aggregate of $26.7 million, all of which remained outstanding as of December 31, 2019. All such debt was governed by the terms of a delayed draw convertible note that permitted NG Advantage to draw up to $26.7 million, subject to certain conditions. All outstanding principal under the note bore interest at a rate of 12.0% per annum, and all unpaid principal and accrued interest under the note was due on the earlier of December 31, 2019, subject to extension at the Company's discretion, or the occurrence of an event of default (subject to notice requirements and cure periods in certain circumstances). In connection with this debt, on June 28, 2019 and November 27, 2019, NG Advantage issued us warrants to purchase 86,879 and 2,000,000 common units, respectively. These intercompany transactions have been eliminated in consolidation.

In February 2020, we converted the principal and accrued interest under the convertible promissory note into common units of NG Advantage resulting in an increase in our controlling interest in NG Advantage to 93.2%.

See Notes 5 and 23 for additional information regarding the convertible promissory note.

Debt Level and Debt Compliance

As of December 31, 2019, we had total indebtedness, excluding finance lease obligations, of $89.1 million in principal amount, of which approximately $56.1 million is expected to become due in 2020. Certain of the agreements governing

our outstanding debt, which are discussed in Note 13, have certain non-financial covenants with which we must comply. As of December 31, 2019, we were in compliance with all of these covenants.

Key Trends

Market for RNG, CNG and LNG as a Vehicle Fuel

According to CARB, RNG and conventional natural gas are cleaner than gasoline and diesel fuel based on the greenhouse gas emissions produced by vehicles operated by these fuels. Additionally, RNG and conventional natural gas are generally less expensive than gasoline and diesel on an energy equivalent basis. According to the U.S. Energy Information Administration, demand for renewable and conventional natural gas fuels in the United States has increased in recent years and is expected to continue to increase. We expect our sales of Redeem RNG and conventional natural gas to grow as more companies look to operate in an increasingly sustainable way. In addition to pressure from politicians, regulators and non-governmental organizations, the investment community has dramatically stepped up demands on companies to diminish their contributions to climate change. We believe that RNG is the best tool available today to reduce climate-harming greenhouse gas and meet sustainability objectives.

The market for natural gas as a vehicle fuel, however, is a relatively new and developing market. As a result, it is challenging to accurately predict natural gas vehicle fuel demand, in general and in any specific geographic and customer markets, and consequently our timing and level of investment in particular markets may not be consistent with any growth in demand in these markets. Further, the new and developing nature of the natural gas vehicles fuel market has led to slow, volatile or unpredictable growth in many sectors. For example, to date, adoption and deployment of natural gas vehicles, in general and in certain of our key customer markets, including heavy-duty trucking, have been slower and more limited than we anticipated. Also, other important markets, including airports, refuse and public transit, have experienced fluctuations in their natural gas adoption, including slower volume and customer growth in 2018 and 2019 that may continue. Moreover, adoption of and demand for the different types of natural gas vehicle fuel, including RNG, CNG and LNG, are subject to significant risks, including decreased LNG volumes in some markets in recent periods that may continue and may not be sufficiently offset by any increase in demand for RNG or CNG. We believe these market conditions have contributed to our lower revenue levels in recent periods.

We believe the slow growth and unpredictability of the market for natural gas vehicle fuels has been caused by a number of factors, including the following:

To the extent these or other factors have contributed to curtailed demand or slowing growth in the market for natural gas as a vehicle fuel, we believe they have also contributed to decreases in station construction activity in certain periods, as the success of this activity is dependent on the success of the natural gas vehicle fuels market generally. Moreover, we believe these factors have materially contributed to the volatility and overall decline in our stock price and market capitalization in recent years, which has and could in the future lead to decreased cash flows and indications of asset or goodwill impairment. If these adverse macroeconomic conditions and other uncertainties in our industry persist, our financial results and stock price may continue to be adversely affected.

In spite of these market conditions, we believe our key customer markets, including heavy-duty trucking, airports, refuse, public transit, industrial and institutional energy users and government fleets, are well-suited for the adoption of natural gas vehicle fuel because they consume relatively high volumes of fuel, refuel at centralized locations or along well-defined routes and/or are facing increasingly stringent emissions or other environmental requirements. We also expect the lower greenhouse gas emissions associated with our Redeem vehicle fuel will result in increased demand for this fuel, resulting in our continued delivery of increasing volumes of Redeem to our vehicle fleet customers. Additionally, we anticipate that, over time, cities and communities in the United States and Canada will follow large cities in Europe in banning dirty diesel vehicles. If these projections materialize, we believe there will be growth in the consumption of natural gas as a vehicle fuel in our key customer and geographic markets, and our goal is to capitalize on this growth if and when it materializes. In that event, we expect our operating costs and capital expenditures would increase in connection with any growth of our business in the future.

Our Performance

Overview. Our gross revenue mostly consists of volume-related revenue, compressor and other equipment sales (before the CEC Combination), station construction sales, and AFTC revenue. Our revenue can vary between periods due to a variety of factors, including, among others, the amount and timing of natural gas vehicle fuel sales, natural gas prices, station construction sales, sales of RINs and LCFS Credits, compressor and other equipment sales (before the CEC Combination), and recognition of government credits, grants and incentives, such as AFTC. In addition, our volume-related revenue has been and may continue to be subject to increased fluctuations as a result of our entry into certain commodity swap arrangements in October 2018, because the changes in fair value of these and certain other derivative instruments, including existing and anticipated fueling contracts under our Zero Now truck financing program, are included in volume-related revenue.

Our cost of sales can also vary between periods due to a variety of factors, including fluctuations in natural gas prices, station construction and labor costs, and compressor equipment costs (before the CEC Combination), as well as the other factors that impact our revenue levels described above.

In addition, our performance in certain periods has been affected by transactions or events that have resulted in significant cash or non-cash gains or losses. For example, our results for 2017 were positively affected by a gain related to repurchases and retirements of our outstanding convertible debt at a discount, and a gain related to the BP Transaction,

but our results for 2017 were negatively affected by significant charges in connection with our closure of certain fueling stations, the decreased operating performance of our former natural gas fueling compressor manufacturing business, our determination of an impairment of assets as a result of the foregoing, and certain other actions. These or other similar gains or losses may not recur regularly, in the same amounts or at all in future periods and, with respect to non-cash gains and losses, do not impact our liquidity.

In the third and fourth quarters of 2017, we took actions we believe will better align our activities and assets with current and anticipated market demand. These actions included a workforce reduction and other measures to reduce overhead costs, which resulted in cash severance costs and certain non-cash stock-based compensation charges; our decision to close certain of our natural gas fueling stations by the end of 2017, which resulted in an impairment of these station assets and certain other cash and non-cash charges; our determination that the assets of CEC, our former subsidiary, were impaired, which resulted in a non-cash charge; and our contribution of CEC to a newly formed joint venture in the CEC Combination. These actions affected our performance in 2017 as a result of the cash expenses and non-cash impairment and other charges, which could be repeated if we decide to implement similar measures in the future but may otherwise limit the comparability of our 2017 results. In addition, these actions will affect our future performance and financial condition. For instance, our fueling station closures and the CEC Combination have decreased our aggregate revenue and cost levels, and we expect these lower levels to continue. In addition, our workforce reduction and other measures to reduce overhead costs have contributed to decreased expenses, particularly selling, general and administrative expenses, and we expect these lower expense levels will also continue. These actions also led us to record asset impairment and other cash and non-cash charges in 2017, and we may determine to record this type of asset or goodwill impairment in future periods due to similar or other events or factors. For example, a sustained decline in our stock price and the resulting decline of our market capitalization or periods of general volatility in our market capitalization, as we have experienced in recent periods, could cause our goodwill to become impaired, which could result in material charges and adversely affect our results of operations.

See “Results of Operations” below for more information about our performance in 2018 and 2019.

Volume. The amount of RNG, CNG and LNG we delivered increased by 9.7% from 2018 to 2019.

In particular, the amount of RNG we sell for vehicle fuel, which is delivered in the form of CNG or LNG and is distributed under the brand name Redeem, has experienced rapid growth in recent years, increasing by 30.2% from 2018 to 2019. This demand for Redeem is attributable to the dramatic reduction in the amount of climate-harming greenhouse gas that can be achieved through the use of Redeem RNG and pressure from politicians, regulators, non-governmental organizations and the investment community directed at companies to reduce their contributions to climate change. To the extent demand for RNG continues to increase, we expect our expanded supply agreement with BP, discussed under “2018‑2020 Developments” above, could increase our volume-related revenue due to increased volumes of RNG vehicle fuel sold and increased generation of RINs and LCFS Credits. In addition, such an increase in RNG demand could also result in more robust competition for supplies of RNG, including from other vehicle fuel providers, gas utilities (which may have distinct advantages in accessing RNG supply, including potential use of ratepayer funds to fund RNG purchases if approved by a utility’s regulatory commission) and other users and providers. We may invest in production projects to help ensure that we have adequate supply of RNG.

RINs and LCFS Credits. When we sell RNG and conventional natural gas for use as a vehicle fuel, we are eligible to generate RINs and LCFS Credits, which we then seek to sell to third parties.

The markets for RINs and LCFS Credits have been volatile and unpredictable in recent periods, and the prices for these credits have been subject to significant fluctuations. For example, in 2019 market prices for RINs were as high as approximately $1.90 and as low as approximately $0.50. Additionally, the value of RINs and LCFS Credits, and consequently the revenue levels we may receive from our sale of these credits, may be adversely affected by changes to the federal and state programs under which these credits are generated and sold. Further, our ability to generate revenue from sales of these credits depends on our strict compliance with these federal and state programs, which are complex and can involve a significant degree of judgment. If the agencies that administer and enforce these programs disagree with our judgments, otherwise determine we are not in compliance, conduct reviews of our activities or make changes to the programs, then our ability to generate or sell these credits could be temporarily restricted pending completion of reviews

or as a penalty, permanently limited or lost entirely, and we could be subject to fines or other sanctions. Any of these outcomes could force us to purchase credits in the open market to cover any credits we have contracted to sell, retire credits we may have generated but not yet sold, reduce or eliminate a significant revenue stream or incur substantial additional and unplanned expenses.

In addition, we recognized no revenue from sales of LCFS Credits during the third and fourth quarters of 2017 because CARB had restricted our ability to sell and transfer LCFS Credits pending completion of an administrative review. We were, however, required to settle preexisting contractual obligations to transfer LCFS Credits to third parties by making cash payments totaling $7.0 million, the equivalent value of the LCFS Credits we would have otherwise transferred to satisfy our obligations. In November 2017, CARB invalidated certain LCFS Credits we had generated in prior periods and released the restriction on our ability to sell and transfer LCFS Credits.

Risk Management Activities

From time to time, we enter into natural gas fuel sales contracts that require us to sell CNG or LNG to our customers at a fixed price. These contracts expose us to the risk that the price of natural gas may increase above the natural gas cost component included in the price at which we are committed to sell the natural gas to our customers.

In an effort to mitigate the volatility of our earnings related to any futures contracts and to reduce our risk related to our fixed price sales contracts, we operate under a natural gas hedging policy pursuant to which we purchase futures contracts to hedge our exposure to variability in expected future cash flows related to a particular fixed price contract or bid. Subject to the conditions set forth in the policy, we purchase futures contracts in quantities reasonably expected to effectively hedge our exposure to cash flow variability related to fixed price sales contracts entered into after the date of the policy. Unless otherwise agreed in advance by our board of directors and the derivatives committee thereof, we will conduct our futures contract activities and enter into fixed price sales contracts only in accordance with our natural gas hedging policy.

Due to the restrictions of our hedging policy, we expect to offer few fixed price sales contracts to our customers. If we do offer a fixed price sales contract, we anticipate including a price component that would cover our estimated cash requirements over the duration of the underlying futures contracts. The amount of this price component will vary based on the anticipated volume and the natural gas price component to be covered under the fixed price sales contract.

In October 2018, in support of the our Zero Now truck financing program, we executed two commodity swap contracts with Total Gas & Power North America, an affiliate of TOTAL and THUSA, for a total of five million diesel gallons annually from April 1, 2019 to June 30, 2024. These commodity swap contracts are intended to manage risks related to the diesel-to-natural gas price spread in connection with the natural gas fuel supply commitments we have made and expect to make in our current and anticipated fueling agreements with fleet operators that participate in the Zero Now program.

Critical Accounting Policies

This discussion is based upon our consolidated financial statements included in this report, which have been prepared in accordance with accounting principles generally accepted in the United States of America (“US GAAP”). The preparation of consolidated financial statements in conformity with US GAAP requires management to make estimates and assumptions that affect the amounts reported in the consolidated financial statements and accompanying notes. Actual results could differ from those estimates and may result in material effects on our operating results and financial position.

We believe the critical accounting policies discussed below affect our more significant estimates made in preparing our consolidated financial statements. See Notes 1 and 2 for more information about these and our other significant accounting policies.

Revenue Recognition

In general, revenue is recognized when control of the promised goods or services is transferred to our customers, in an amount that reflects the consideration to which we expect to be entitled in exchange for the goods or services. To  

achieve that core principle, a five-step approach is applied: (1) identify the contract with a customer, (2) identify the performance obligations in the contract, (3) determine the transaction price, (4) allocate the transaction price to the performance obligations in the contract, and (5) recognize revenue allocated to each performance obligation when we satisfy the performance obligation. A performance obligation is a promise in a contract to transfer a distinct good or service to the customer, and is the unit of account for revenue recognition.

We recognize revenue on various products and services.

Our volume-related revenue primarily consists of sales of RNG, CNG and LNG fuel, O&M services, and RINs and LCFS Credits in addition to changes in fair value of our derivative instruments.

Fuel and O&M services are sold pursuant to contractual commitments over defined goods-and-service delivery periods. These contracts typically include a stand-ready obligation to supply natural gas and/or provide O&M services daily based on a committed and agreed upon routine maintenance schedule or when and if called upon by the customer.

We recognize fuel and O&M services revenue in the amount to which we have the right to invoice. We have a right to consideration based on the amount of gasoline gallon equivalents of natural gas dispensed by the customer and current pricing conditions, which are typically billed to the customer on a monthly basis. Since payment terms are less than a year, we have elected the practical expedient which allows us to not assess whether a customer contract has a significant financing component.

We sell RIN Credits and LCFS Credits to third parties that need the credits to comply with federal and state requirements. Revenue is recognized on these credits when there is an agreement in place to monetize the credits at a determinable price.

Changes in fair value of derivative instruments relates to our commodity swap and customer fueling contracts. The contracts are measured at fair value with changes in the fair value recorded in our consolidated statements of operations in the period incurred. The amounts are classified as revenue because our commodity swap contracts are used to economically offset the risk associated with the diesel-to-natural gas price spread resulting from anticipated customer fueling contracts under our Zero Now truck financing program.

Station construction contracts are generally short-term, except for certain larger and more complex stations, which can take up to 24 months to complete. For most of our station construction contracts, the customer contracts with us to provide a significant service of integrating a complex set of tasks and components into a single station. Hence, the entire contract is accounted for as one performance obligation.

We recognize revenue over time as we perform under our station construction contracts because of the continual transfer of control of the goods to the customer, who typically controls the work in process. Revenue is recognized based on the extent of progress towards completion of the performance obligation and is recorded proportionally as costs are incurred. Costs to fulfill our obligations under these contracts typically include labor, materials and subcontractors’ costs, other direct costs and an allocation of indirect costs.

Refinements of estimates to account for changing conditions and new developments are continuous and characteristic of the process. Many factors that can affect contract profitability may change during the performance period of the contract, including differing site conditions, the availability of skilled contract labor, the performance of major suppliers and subcontractors, and unexpected changes in material costs. Because a significant change in one or more of these estimates could affect the profitability of these contracts, the contract price and cost estimates are reviewed periodically as work progresses and adjustments proportionate to the cost-to-cost measure of progress are reflected in contract revenues in the reporting period when such estimates are revised as discussed above. Provisions for estimated losses on uncompleted contracts are recorded in the period in which the losses become known.

In certain contracts with our customers, we agree to provide multiple goods or services, including construction of and sale of a station, O&M services, and sale of fuel to the customer. These contracts have multiple performance obligations because the promise to transfer each separate good or service is separately identifiable and is distinct. This evaluation

requires significant judgment and the decision to combine a group of contracts or separate the combined or single contract into multiple performance obligations could change the amount of revenue recognized in one or more periods.

We allocate the contract price to each performance obligation using best estimates of the standalone selling price of each distinct good or service in the contract. The primary method used to estimate the standalone selling price for fuel and O&M services is observable standalone sales, and the primary method used to estimate the standalone selling price for station construction sales is the expected cost plus a margin approach because we sell customized customer-specific solutions. Under this approach, we forecast expected costs of satisfying a performance obligation and then add an appropriate margin for the good or service.

AFTC is considered variable consideration because it can either increase or decrease the transaction price based on volumes of vehicle fuel sold. Additionally, AFTC is not recognized as revenue until it is authorized through federal legislation, which also provides a determinable price. We recognize revenue in the period the credit is authorized through federal legislation.

We collect and remit taxes assessed by various governmental authorities that are imposed on and concurrent with revenue-producing transactions between us and our customers. These taxes may include, among others, fuel, sales and value-added taxes. We report the collection of these taxes on a net basis and they are excluded from revenue and cost of goods sold.

Impairment of Goodwill and Long-Lived Assets

Goodwill represents the excess of costs incurred over the fair value of the net assets of acquired businesses. We assess our goodwill using either a qualitative or quantitative approach to determine whether it is more likely than not that the fair value of our reporting unit is less than its carrying value. We are required to use judgment when applying the goodwill impairment test, including, among other considerations, the identification of reporting unit(s), the assessment of qualitative factors, and the estimation of fair value of a reporting unit in the quantitative approach. We determined that we are a single reporting unit for the purpose of goodwill impairment tests. We perform the impairment test annually on October 1, or more frequently if facts or circumstances change that would indicate that the carrying amount may be impaired.

The qualitative goodwill assessment includes the potential effect on a reporting unit’s fair value of certain events and circumstances, including its enterprise value, macroeconomic conditions, industry and market considerations, cost factors, and other relevant entity-specific events. If it is determined, based upon the qualitative assessment, that it is more likely than not that the reporting unit’s fair value is less than its carrying amount, then a quantitative impairment test is performed. Alternatively, we may bypass the qualitative assessment for a reporting unit and directly perform the quantitative assessment.

The quantitative assessment estimates the reporting unit's fair value based on its market capitalization plus an assumed control premium as evidence of fair value. The estimates used to determine the fair value of the reporting unit may change based on results of operations, macroeconomic conditions stock price fluctuations or other factors. Changes in these estimates could materially affect our assessment of the fair value and goodwill impairment for the reporting unit.

For our most recent goodwill impairment test, which was our annual test performed on October 1, 2019, we performed a quantitative impairment assessment for the reporting unit as described above. In this test, the fair value of the reporting unit exceeded its carrying value by 9%.

We evaluated the volatility in the market price of our common stock subsequent to our annual test date through December 31, 2019, and considered whether there were any other events or circumstances that would more likely than not reduce the fair value of our reporting unit below its carrying value on a sustained basis, and concluded it was not more likely than not that the fair value of our reporting unit decreased below its carrying value, on a sustained basis. As a result, an interim impairment test was not considered necessary during the three months ended December 31, 2019.

If a decline in the market price of our common stock and our market capitalization were sustained, or if other events or circumstances change that would more likely than not reduce the fair value of our reporting unit below its carrying

value, on a sustained basis, then we may perform impairment tests more frequently and it is possible that our goodwill could become impaired, which could result in a material charge and adversely affect our results of operations.

We review the carrying value of our long-lived assets, including property and equipment and intangible assets with finite useful lives, for impairment whenever events or changes in circumstances indicate that the carrying value of an asset or asset group may not be recoverable. Events that could result in an impairment review include, among others, a significant decrease in the operating performance of a long-lived asset or asset group or the decision to close a fueling station. Impairment testing involves a comparison of the sum of the undiscounted future cash flows of the asset or asset group to its carrying amount. If the sum of the undiscounted future cash flows exceeds the carrying amount, then no impairment exists. If the carrying amount exceeds the sum of the undiscounted future cash flows, then a second step is performed to determine the amount of impairment, if any, to be recognized. An impairment loss is recognized to the extent that the carrying amount of the asset or asset group exceeds its fair value. The fair value of the asset or asset group is based on estimated discounted future cash flows of the asset or asset group using a discount rate commensurate with the related risk. The estimate of future cash flows requires management to make assumptions and to apply judgment, including forecasting future sales and expenses and estimating useful lives of the assets. These estimates can be affected by a number of factors, including, among others, future results, demand and economic conditions, many of which can be difficult to predict.

Income Taxes

Income taxes are computed using the asset and liability method. Under this method, deferred income taxes are recognized by applying enacted statutory tax rates applicable to future years to differences between the tax bases and financial carrying amounts of existing assets and liabilities. The impact on deferred taxes of changes in tax rates and laws, if any, are applied to the years during which temporary differences are expected to be settled and are reflected in the consolidated financial statements in the period of enactment. Valuation allowances are established when management determines it is more likely than not that deferred tax assets will not be realized. When evaluating the need for a valuation analysis, we use estimates involving a high degree of judgment including projected future US GAAP income and the amounts and estimated timing of the reversal of any deferred tax assets and liabilities.

We have a recognition threshold and a measurement attribute for the financial statement recognition and measurement of tax positions taken or expected to be taken in a tax return. For those benefits to be recognized, a tax position must be more likely than not to be sustained upon examination by taxing authorities based on the technical merits of the position. The amount recognized is measured as the largest amount of benefit that has a greater than 50% likelihood of being realized upon ultimate settlement. We recognize potential accrued interest and penalties related to unrecognized tax benefit in income tax expense.

We operate within multiple domestic and foreign taxing jurisdictions and are subject to audit in these jurisdictions. These audits can involve complex issues, which may require an extended period of time to resolve. Although we believe that adequate consideration has been given to these issues, it is possible that the ultimate resolution of these issues could be significantly different than originally estimated.

Fair Value Measurements

We have established a framework that follows the authoritative guidance for fair value measurements with respect to assets and liabilities that are measured at fair value on a recurring basis and non-recurring basis. Under the framework, fair value is defined as the exit price, or the amount that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants, as of the measurement date. The framework also establishes a hierarchy for inputs used in measuring fair value that maximizes the use of observable inputs and minimizes the use of unobservable inputs by requiring that the most observable inputs be used when available. Observable inputs are inputs market participants would use in valuing the asset or liability and are developed based on market data obtained from sources independent of our Company. Unobservable inputs are inputs that reflect our assumptions about the factors market participants would use in valuing the asset or liability and are developed based upon the best information available in the circumstances. The hierarchy consists of the following three levels: Level 1 inputs are quoted prices (unadjusted) in active markets for identical assets or liabilities; Level 2 inputs include quoted prices for similar assets or liabilities in active markets, quoted prices for identical or similar assets or liabilities in markets that are not active, and inputs (other than

quoted prices) that are observable for the asset or liability, either directly or indirectly; Level 3 inputs are unobservable inputs for the asset or liability. Categorization within the valuation hierarchy is based upon the lowest level of input that is significant to the fair value measurement.

Our significant uses of fair value measurements include the valuation of assets disposed and liabilities extinguished related to business divestitures and impairment of long-lived assets, as well as the valuation of commodity swaps and customer contracts, and warrants, all of which requires significant judgment.

Recently Adopted Accounting Changes and Recently Issued and Adopted Accounting Standards.

See Note 1 for information about recently adopted accounting changes and recently issued accounting standards.

Results of Operations

The discussions below compare our results of operations in 2019 and 2018. Historical results are not indicative of the results to be expected in the current period or any future period.

2019 Compared to 2018

The table below presents, for each period, each line item of our statement of operations data as a percentage of our total revenue for the period. The narrative that follows provides a comparative discussion of certain of these line items between periods.

Revenue.    Revenue decreased by $2.4 million to $344.1 million for 2019, from $346.4 million for 2018. This decrease was primarily due to the unfavorable change in fair value of our commodity swap and customer contracts entered into in connection with our Zero Now truck financing program, lower station construction sales and lower revenue from

the sale of used trucks, partially offset by an increase in AFTC revenue, as well as an increase in revenue from higher volumes.

Volume-related revenue, excluding the impact of the change in fair value of our commodity swap and customer contracts entered into in connection with our Zero Now truck financing program, increased by $3.8 million between periods, attributable to an increase in gallons of CNG and LNG delivered, and increased revenue from RINs and LCFS Credits. The impact to volume-related revenue as a result of the change in fair value of our commodity swap and customer contracts entered into in connection with our Zero Now truck financing program was $(16.9) million, as we recognized an unrealized gain of $10.3 million in 2018 compared to an unrealized loss of $(6.6) million in 2019 (see Note 8 for more information).

Our effective price per gallon charged decreased by $0.06 per gallon to $0.70 per gallon in 2019 compared to $0.76 in 2018, excluding the effect of the change in fair value of derivative instruments discussed above. Our effective price per gallon is defined as revenue generated from selling RNG, CNG, LNG and any related RINs and LCFS Credits and providing O&M services to our vehicle fleet customers at stations we do not own and for which we receive a per-gallon or fixed fee, all divided by the total GGEs delivered less GGEs delivered by non-consolidated entities, such as entities that are accounted for under the equity method.

Station construction sales decreased by $2.4 million between periods, due to fewer construction projects.

AFTC revenue increased by $20.4 million between periods due to our recognition in 2019 of AFTC revenue for the vehicle fuel we sold in 2018 and 2019. In 2018, we recognized AFTC revenue for the vehicle fuel we sold in 2017.

Cost of sales.    Cost of sales decreased by $0.8 million to $212.1 million in 2019, from $212.9 million in 2018. This decrease was primarily due to a $1.6 million decrease in station construction costs due to fewer construction projects, and a $7.6 million decrease in costs to purchase used heavy-duty trucks that we sold to our customers. These decreases were partially offset by an $8.8 million increase in gas commodity costs due to the increase in gallons delivered during 2019 partially offset by a lower average cost per gallon in 2019 compared to 2018.

Our effective cost per gallon decreased by $0.02 per gallon to $0.47 per gallon in 2019 compared to $0.49 per gallon in 2018. Our effective cost per gallon is defined as the total costs associated with delivering natural gas, including gas commodity costs, transportation fees, liquefaction charges, and other site operating costs, plus the total cost of providing O&M services at stations that we do not own and for which we receive a per-gallon or fixed fee, including direct technician labor, indirect supervisor and management labor, repair parts and other direct maintenance costs, all divided by the total GGEs delivered less GGEs delivered by non-consolidated entities, such as entities that are accounted for under the equity method. The decrease in our effective cost per gallon was due to decreases in natural gas prices and transportation costs.

Change in fair value of derivative warrants. Change in fair value of derivative warrants, all of which were issued by our subsidiary, NG Advantage, changed from an expense of $0.5 million in 2018, to income of $1.0 million in 2019 due to a change in the estimated fair value.

Selling, general and administrative.    Selling, general and administrative expenses decreased by $3.8 million to $73.4 million for 2019, from $77.2 million for 2018. This decrease was primarily driven by continued cost reduction efforts.

Depreciation and amortization.    Depreciation and amortization decreased by $2.2 million to $49.6 million in 2019, from $51.9 million in 2018, primarily due to a lower amount of depreciable assets.

Interest expense.    Interest expense decreased by $8.4 million to $7.6 million in 2019, from $15.9 million in 2018. This decrease was primarily due to a reduction of outstanding indebtedness between periods.

Other income (expense), net.    Other income (expense), net, changed from an expense of $0.6 million in 2018 to income of $2.0 million in 2019, primarily due to gains recorded from disposal of certain assets.

Loss from equity method investments. Loss from equity method investments decreased by $2.6 million between periods, which was primarily attributable to improved operating results from SAFE&CEC S.r.l.

Gain from sale of certain assets of subsidiary. In 2019, we recorded a gain of $7.5 million as a result of the satisfaction of certain performance criteria related to the assets sold in the BP Transaction and an amendment to the related Asset Purchase Agreement. In 2018, we recorded a gain of $4.8 million as a result of the satisfaction of certain performance criteria related to the assets sold in the BP Transaction. See Note 4 for more information.

Loss from formation of equity method investment. In 2018, we recorded a loss of $1.2 million related to costs incurred in satisfaction of commitments made in connection with the CEC Combination. There was no comparable loss in 2019.

Income tax expense.    Income tax expense increased between periods, primarily due an increase in deferred taxes associated with goodwill which were partially offset by a reduction in the Company’s expected state tax expense.

Loss attributable to noncontrolling interest.    In 2019, we recorded a $7.2 million loss for the noncontrolling interest in the net loss of NG Advantage, compared to a $5.4 million loss for 2018. The noncontrolling interest in NG Advantage represents a 37.0% and 35.4% minority interest that was held by third parties during 2018 and 2019, respectively.

Seasonality and Inflation

To some extent, we experience seasonality in our results of operations. Some of our customers tend to consume more natural gas vehicle fuel in the summer months, when buses and other fleet vehicles use more fuel to power their air conditioning systems. Natural gas commodity prices tend to be higher in the fall and winter months, due to increased overall demand for natural gas for heating during these periods.

Historically, inflation has not significantly affected our operating results; however, costs for construction, repairs, maintenance, electricity and insurance are all subject to inflationary pressures, which could affect our ability to maintain our stations adequately, build new stations, expand our existing facilities or pursue additional facilities, and could materially impact our operating costs.

Liquidity and Capital Resources

Liquidity

Liquidity is the ability to meet present and future financial obligations through operating cash flows, the sale or maturity of investments or the acquisition of additional funds through capital management. Our financial position and liquidity are, and will continue to be, influenced by a variety of factors, including the level of our outstanding indebtedness and the principal and interest we are obligated to pay on our indebtedness, which could be influenced by the potential discontinuance of LIBOR for certain of our debt instruments that tie interest rates to this metric; the amount and timing of any additional debt or equity financing we may pursue; determinations to buy-out future commitments; our capital expenditure requirements; any merger, divestiture or acquisition activity; and our ability to generate cash flows from our operations. We expect cash provided by our operating activities to fluctuate as a result of a number of factors, including our operating results and the factors that affect these results, including the amount and timing of our natural gas vehicle fuel sales, station construction sales, sales of RINs and LCFS Credits and recognition of government credits, grants and incentives, if any; fluctuations in commodity, station construction and labor costs and natural gas, RIN and LCFS Credit prices; variations in the fair value of certain of our derivative instruments that are recorded in revenue; and the amount and timing of our billing, collections and liability payments, as discussed under “Key Trends-Our Performance” above.

Cash Flows

Operating Activities. Cash provided by operating activities was $12.3 million in 2019, compared to $38.0 million in 2018. The decrease in cash provided by operating activities was primarily attributable to the AFTC revenue collected in 2018 and changes in working capital resulting from the timing of receipts and payments of cash.

Investing Activities. Cash used in investing activities was $1.5 million in 2019, compared to cash provided by investing activities of $54.4 million in 2018. The decrease in cash provided by investing activities was attributable to a decrease in maturities and sales of short-term investments in 2019, partially offset by an increase in proceeds from property and equipment disposals and an increase in earn-out proceeds received in connection with the BP Transaction. The decrease in cash provided by investing activities in 2019 was also attributable to an increase in purchases of property and equipment between periods.

Financing Activities. Cash provided by financing activities was $7.7 million in 2019, compared to cash used in financing activities of $95.2 million in 2018. Cash provided by financing activities in 2019 was primarily attributable to proceeds from debt instruments and finance lease obligations, partially offset by repayments of debt instruments and finance lease obligations. Cash used in financing activities in 2018 consisted primarily of our repayment of debt instruments and finance lease obligations, partially offset by cash proceeds, net of fees, from our issuance of stock in the Total Private Placement.

Capital Expenditures, Indebtedness and Other Uses of Cash

We require cash to fund our capital expenditures, operating expenses and working capital and other requirements, including costs associated with fuel sales; outlays for the design and construction of new fueling stations; additions or other modifications to existing fueling stations; debt repayments and repurchases; investments in RNG production; maintenance of LNG production facilities; supporting our operations, including maintenance and improvements of our infrastructure; supporting our sales and marketing activities, including support of legislative and regulatory initiatives; financing natural gas vehicles for our customers; any investments in other entities; any mergers or acquisitions; pursuing market expansion as opportunities arise, including geographically and to new customer markets; and to fund other activities or pursuits and for other general corporate purposes.

Our business plan calls for approximately $18.0 million in capital expenditures in 2020. These capital expenditures primarily relate to the construction of CNG fueling stations, IT software and equipment and LNG plant maintenance costs and we expect to fund these expenditures primarily through cash on hand and cash generated from operations.

In addition, NG Advantage may spend as much as $12.8 million to purchase additional equipment in support of its operations and customer contracts or buy-out future commitments, among other things.

We had total indebtedness, consisting of our debt and finance leases, of approximately $92.4 million in principal amount as of December 31, 2019, of which approximately $56.7 million, $6.9 million, $7.0 million, $11.9 million, $9.6 million and $0.3 million is expected to become due in 2020, 2021, 2022, 2023, 2024 and thereafter, respectively. Based on outstanding debt balances and applicable interest rates at December 31, 2019, we expect our total interest payment obligations relating to our indebtedness to be approximately $4.8 million for the year ending December 31, 2020. In addition, in connection with implementing our Zero Now truck financing program, we have entered into agreements that permit us to incur a material amount of additional debt on a delayed draw basis and obligate us to make interest and other fee payments that vary in amount based on the outstanding principal of this debt and certain other factors; none of this potential debt nor the related interest and other payments are included in the foregoing estimates other than the principal amount of $4.4 million drawn as of December 31, 2019. Although we believe we have sufficient liquidity and capital resources to repay our debt coming due in the next 12 months, we may elect to pursue alternatives, such as refinancing or debt or equity offerings, to increase our cash management flexibility. As of December 31, 2019, we have $50.0 million of outstanding 7.5% convertible notes outstanding, which mature in June 2020. We are permitted to issue up to 14.0 million shares of common stock to repay a portion of the principal amount of these outstanding convertible notes.

We intend to make payments under our various debt instruments when due and pursue opportunities for earlier repayment and/or refinancing if and when these opportunities arise.

Sources of Cash

Historically, our principal sources of liquidity have consisted of cash on hand, cash provided by our operations, including, if available, AFTC and other government credits, grants and incentives, cash provided by financing activities,

and sales of assets. As of December 31, 2019, we had total cash and cash equivalents and short-term investments of $106.1 million, compared to $95.5 million as of December 31, 2018.

We expect cash provided by our operating activities to fluctuate depending on our operating results, which can be affected by the factors described above, as well as the other factors described in this MD&A and “Item 1A. Risk Factors” of this report.

In October 2018 and January 2019, we entered into agreements to implement our Zero Now truck financing program, which permit us to incur up to an additional $100.0 million of indebtedness through the beginning of January 2022, obligate us to make certain interest and other fee payments in connection with this debt and THUSA’s related guaranty (which payments will vary in amount but will be owed by us regardless of the revenue we may receive from the program), and subject us to potential additional payments in connection with related commodity swap arrangements. We are permitted to use any proceeds we receive under these agreements solely to fund the incremental cost of trucks purchased or financed by operators that participate in the Zero Now program. See “Recent Developments” and “Key Trends” above and Note 13 of this report for more information.

We believe our cash and cash equivalents and short-term investments and anticipated cash provided by our operating and financing activities will satisfy our business requirements for at least the 12 months following the date of this report. Subsequent to that period, we may need to raise additional capital to fund any planned or unanticipated capital expenditures, investments, debt repayments or other expenses that we cannot fund through cash on-hand, cash provided by our operations or other sources. Moreover, we may use our cash resources faster than we predict due to unexpected expenditures or higher-than-expected expenses, in which case we may need to seek capital from alternative sources sooner than we anticipate.

The timing and necessity of any future capital raise would depend on various factors, including our rate and volume of, and prices for, natural gas sales and other volume-related activity, new station construction, debt repayments (either before or at maturity) and any potential mergers, acquisitions, investments, divestitures or other strategic relationships we may pursue, as well as the other factors that affect our revenue and expense levels as described in this MD&A and elsewhere in this report.

We may seek to raise additional capital through one or more sources, including, among others, selling assets, obtaining new or restructuring existing debt, obtaining equity capital, or any combination of these or other potential sources of capital. We may not be able to raise capital when needed, on terms that are favorable to us or our stockholders or at all. Any inability to raise necessary capital may impair our ability to develop and maintain natural gas fueling infrastructure, invest in strategic transactions or acquisitions or repay our outstanding indebtedness and may reduce our ability to support and build our business and generate sustained or increased revenue.

Contractual Obligations

The table below represents the scheduled maturities of our contractual obligations as of December 31, 2019. This table excludes certain potential contractual obligations because they may involve future cash payments that are considered uncertain and cannot be estimated because they vary based upon future conditions; however, the exclusion of these

obligations should not be construed as an implication that they are immaterial, as they could significantly affect our short- and long-term liquidity and capital resource needs depending on a variety of future events, facts and conditions.

Off-Balance Sheet Arrangements

As of December 31, 2019, we had the following off-balance sheet arrangements that have had, or are reasonably likely to have, a material current or future effect on our financial condition, changes in financial condition, revenue or expenses, results of operations, liquidity, capital expenditures or capital resources:

We provide surety bonds primarily for construction contracts in the ordinary course of our business, as a form of guarantee. No liability has been recorded in connection with our surety bonds because, based on historical experience and available information, we do not believe it is probable that any amounts will be required to be paid under these arrangements for which we will not be reimbursed.

As of December 31, 2019, we had two long-term natural gas purchase contracts with a take-or-pay commitment, which require us to purchase minimum volumes of natural gas at index-based prices and expire in December 2020 and

June 2022, respectively. Additionally, as of December 31, 2019, we had quarterly fixed-price natural gas purchase contracts with take-or-pay commitments extending through June 2023.

NG Advantage has entered into an arrangement with BP for the supply, sale and reservation of a specified volume of CNG transportation capacity until March 2022. In connection with the arrangement, on February 28, 2018, we entered into a guaranty agreement with NG Advantage and BP in which we guarantee NG Advantage’s payment obligations to the customer in the event of a default by NG Advantage under the supply arrangement, in an amount up to $30.0 million plus related fees. Our guaranty is in effect until thirty days following our notice to BP of termination.

In addition, as of December 31, 2019, we had a fixed supply arrangement with UPS for the supply and sale of 170.0 million GGEs of RNG through March 2026.

Item 7A.   Quantitative and Qualitative Disclosures about Market Risk.

In the ordinary course of our business, we are exposed to various market risks, including commodity price risks, risks related to foreign currency exchange rates, and risks related to fluctuations in interest rates.

Commodity Price Risk

We are subject to market risk with respect to our sales of natural gas, which have historically been subject to volatile market conditions. Our exposure to market risk is heightened when we have a fixed-price sales contract with a customer that is not covered by a futures contract, or when we are otherwise unable to pass through natural gas price increases to customers. Natural gas prices and availability are affected by many factors, including, among others, drilling activity, supply, weather conditions, overall economic conditions and foreign and domestic government regulations.

Natural gas costs represented $83.3 million, $94.9 million and $94.0 million of our cost of sales in 2017, 2018 and 2019, respectively.

In October 2018, in support of our Zero Now truck financing program, we entered into two commodity swap contracts with Total Gas & Power North America, an affiliate of TOTAL and THUSA, for a total of five million diesel gallons annually from April 1, 2019 to June 30, 2024. These commodity swap contracts are intended to manage risks related to the diesel-to-natural gas price spread in connection with the natural gas fuel supply commitments we expect to make in our anticipated fueling agreements with fleet operators that participate in the Zero Now truck financing program.

We have prepared a sensitivity analysis to estimate our exposure to price risk with respect to our commodity swap contracts. If the diesel-to-natural gas price spread were to fluctuate by 10% as of December 31, 2019, we would expect a corresponding fluctuation in the fair value of our commodity swap contracts of approximately $5.8 million.

Foreign Currency Exchange Rate Risk

Before completion of the CEC Combination on December 29, 2017, we had foreign operations that exposed us to foreign currency exchange gains and losses. Since the functional currency of those foreign subsidiaries is their local currency, the currency effects of translating the financial statements of the foreign subsidiaries, which operate in local currency environments, are included in the accumulated other comprehensive loss component of consolidated equity in our consolidated financial statements and do not impact earnings.

Foreign currency transaction gains and losses not in these subsidiaries’ functional currency, however, do impact earnings, but these amounts were not material for 2018 and 2019.  For the years ended December 31, 2018 and 2019, our primary exposure to foreign currency exchange rates related to our other Canadian operations that had certain outstanding accounts receivable and accounts payable denominated in the U.S. dollar, which were not hedged.

We have prepared a sensitivity analysis to estimate our exposure to market risk with respect to our monetary transactions denominated in a foreign currency. If the exchange rates on these assets and liabilities were to fluctuate by

10% from the rates as of December 31, 2019, we would expect a corresponding fluctuation in the value of the assets and liabilities of approximately $0.3 million.

Interest Rate Risk

As of December 31, 2019, we had $4.4 million of debt that bears interest at a rate equal to LIBOR plus 1.30% per annum. Thus, our interest expense would fluctuate with a change in LIBOR. If LIBOR were to increase or decrease by 1% for the year, our annual interest expense would increase or decrease by approximately $44,000.

The term credit agreement with SG permits the Company to draw loans from time to time through the beginning of January 2022. These loans are subject to an interest rate indexed to LIBOR which is expected to be discontinued after 2021. We intend to monitor the developments with respect to the potential discontinuance of LIBOR after 2021 and work with our lenders under the credit agreement, including SG, and any other indebtedness with an interest rate tied to LIBOR to minimize the effect of such a discontinuance on our financial condition and results of operations; however, the effect of the anticipated discontinuance of LIBOR on us and our debt instruments remains uncertain. If our lenders have increased costs due to changes in LIBOR, we may experience potential increases in interest rates on our variable rate debt, which could adversely impact our interest expense, results of operations and cash flows.

Item 8.   Financial Statements and Supplementary Data.

The following tables set forth our quarterly consolidated statements of operations data for the eight quarters ended December 31, 2019. The information for each quarter is unaudited and we have prepared the information on the same basis as the audited consolidated financial statements included in this report. This information includes all adjustments that management considers necessary for the fair presentation of such data, which include only normal recurring adjustments. See Item 7. Management’s Discussion and Analysis of Financial Condition and Results of Operations of this report for descriptions of the effects of any unusual or infrequently occurring items recognized in any of the periods covered by the below quarterly data. The quarterly data should be read together with our consolidated financial statements and related

notes included in this report. The results of operations for any one quarter are not necessarily indicative of results to be expected in the current period or any future period.