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UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, DC 20549

FORM 10-Q

QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF
THE SECURITIES EXCHANGE ACT OF 1934

For the quarterly period ended September 30, 2009

Commission File Number: 001-33480

CLEAN ENERGY FUELS CORP.
(Exact name of registrant as specified in its charter)

3020 Old Ranch Parkway, Suite 400, Seal Beach CA 90740
(Address of principal executive offices, including zip code)

(562) 493-2804
(Registrant's telephone number, including area code)

        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. ý

        Indicate by check mark whether the registrant has submitted electronically and posted on its corporate Web site, if any, every Interactive Data File required to be submitted and posted pursuant to Rule 405 of Regulation S-T (§232,405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit and post such files). Yes o    No o

        Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, or a smaller reporting company. See definitions of "large accelerated filer," "accelerated filer," and "smaller reporting company" in Rule 12b-2 of the Exchange Act. (Check one):

        Indicate by check mark whether the registrant is a shell company (as defined by Rule 12b-2 of the Act). Yes o    No ý

        As of November 5, 2009, there were 59,742,045 shares of the registrant's common stock, par value $0.0001 per share, issued and outstanding.

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CLEAN ENERGY FUELS CORP. AND SUBSIDIARIES
INDEX

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PART I.—FINANCIAL INFORMATION

Item 1.—Financial Statements (Unaudited)

Clean Energy Fuels Corp. and Subsidiaries

Condensed Consolidated Balance Sheets

December 31, 2008 and September 30, 2009 (Unaudited)

See accompanying notes to condensed consolidated financial statements.

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Clean Energy Fuels Corp. and Subsidiaries

Condensed Consolidated Statements of Operations

For the Three Months and Nine Months Ended

September 30, 2008 and 2009

(Unaudited)

See accompanying notes to condensed consolidated financial statements.

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Clean Energy Fuels Corp.

Condensed Consolidated Statements of Cash Flows

For the Nine Months Ended September 30, 2008 and 2009

(Unaudited)

See accompanying notes to condensed consolidated financial statements.

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CLEAN ENERGY FUELS CORP. AND SUBSIDIARIES

NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS

(Unaudited)

Note 1—General

        Nature of Business:    Clean Energy Fuels Corp. (the "Company") is engaged in the business of selling natural gas fueling solutions to its customers primarily in the United States and Canada. The Company has a broad customer base in a variety of markets including public transit, refuse, airports and regional trucking. The Company operates, maintains or supplies approximately 195 natural gas fueling locations in Arizona, California, Colorado, District of Columbia, Georgia, Maryland, Massachusetts, Nevada, New Jersey, New Mexico, New York, Ohio, Oklahoma, Texas, Virginia, Washington and Wyoming within the United States, and in British Columbia and Ontario within Canada. The Company also generates revenue through operation and maintenance agreements with certain customers, through building and selling or leasing natural gas fueling stations to its customers, and through financing its customers' vehicle purchases. In April 2008, the Company opened its first compressed natural gas ("CNG") station in Lima, Peru through the Company's joint venture, Clean Energy del Peru. In August 2008, the Company acquired 70% of the outstanding membership interests of Dallas Clean Energy, LLC ("DCE"). DCE owns a facility that collects, processes and sells renewable biomethane collected from a landfill in Dallas, Texas. On October 1, 2009, the Company acquired 100% of BAF Technologies, Inc., a company that provides natural gas conversions, alternative fuel systems, application engineering, service and warranty support and research and development for natural gas vehicles.

        Basis of Presentation:    The accompanying interim unaudited condensed consolidated financial statements include the accounts of the Company and its subsidiaries, and, in the opinion of management, reflect all adjustments, which include only normal recurring adjustments, necessary to state fairly the Company's financial position, results of operations and cash flows for the three and nine months ended September 30, 2008 and 2009. All intercompany accounts and transactions have been eliminated in consolidation. The three and nine month periods ended September 30, 2008 and 2009 are not necessarily indicative of the results to be expected for the year ending December 31, 2009 or for any other interim period or for any future year.

        Certain information and disclosures normally included in the notes to consolidated financial statements have been condensed or omitted pursuant to the rules and regulations of the Securities and Exchange Commission (the "SEC"), but the resultant disclosures contained herein are in accordance with accounting principles generally accepted in the United States of America as they apply to interim reporting. The condensed consolidated financial statements should be read in conjunction with the consolidated financial statements as of and for the year ended December 31, 2008 that are included in the Company's Annual Report on Form 10-K filed with the SEC on March 16, 2009.

        The Company has evaluated its subsequent events through November 9, 2009.

Note 2—Acquisitions

Landfill Operation

        On August 15, 2008, the Company and Cambrian Energy McCommas Bluff LLC ("Cambrian") formed a joint venture to acquire all of the outstanding membership interests of DCE which owns a facility that collects, processes and sells landfill gas at the McCommas Bluff landfill located in Dallas, Texas. This acquisition enables the Company to participate in the production of pipeline quality renewable biomethane which may be used as a vehicle fuel.

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CLEAN ENERGY FUELS CORP. AND SUBSIDIARIES

NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS (Continued)

(Unaudited)

Note 2—Acquisitions (Continued)

        The Company paid an aggregate of $19.6 million, including transaction costs, to acquire a 70% interest in DCE. Also as part of the transaction, the Company granted DCE's minority investor an exclusive, non-assignable option to purchase from the Company up to and including a 19% membership interest in DCE. The exercise price of the option is $368,000 for each 1%, up to $6,992,000 for the total 19%. The option may be exercised as a whole or in part (but only in 1% increments) during the ten-year period commencing on the date which the loan made by the Company to DCE has been repaid in full.

        The Company borrowed $18.0 million from PlainsCapital Bank ("PCB") to finance its acquisition of its membership interests in DCE. The Company also obtained a $12.0 million line of credit from PCB to finance capital improvements of the DCE processing facility pursuant to a loan made by the Company to DCE and to pay certain costs and expenses related to the acquisition and the PCB loan. As of September 30, 2009, the Company had borrowed $12.0 million under the line of credit (see note 10). On October 9, 2009, the Company repaid in full the $18 million term loan and simultaneously amended its loan agreement with PCB to obtain a $20 million line of credit with PCB (see note 21).

        The Company accounted for this acquisition in accordance with authoritative guidance for business combinations which requires the Company to recognize the assets acquired, the liabilities assumed, and any non-controlling interest in the acquiree at the acquisition date, measured at their fair values as of that date of acquisition. The following table summarizes the allocation of the aggregate purchase price to the fair value of the assets acquired and liabilities assumed, net of Cambrian's minority interest, in the DCE acquisition:

        Management allocated approximately $21.8 million to the identifiable intangible asset related to the fair value of DCE's landfill lease with the City of Dallas that was acquired with the acquisition. The fair value of the identifiable intangible asset will be amortized on a straight-line basis over the remaining life of the lease, approximately 16.5 years at the acquisition date.

        The results of DCE's operations have been included in the Company's consolidated financial statements since August 15, 2008. The pro-forma effect of the acquisition is not material to the Company's results of operations for the years ended December 31, 2007 and 2008.

Operating and Maintenance Contracts

        In May 2009, the Company acquired four compressed natural gas operations and maintenance services contracts for $5.6 million in cash. The Company recorded $0.5 million to tangible assets and $5.1 million of intangible assets related to customer relationships, which are being amortized over their

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CLEAN ENERGY FUELS CORP. AND SUBSIDIARIES

NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS (Continued)

(Unaudited)

Note 2—Acquisitions (Continued)

expected lives of eight years. The results of operations of the acquired contracts are included in the Company's consolidated financial statements from their acquisition dates forward, which are May 2009 for two of the contracts and June 2009 for the remaining two contracts. The pro-forma effect of the acquisition is not material to the Company's results of operations for the year ended 2008.

Note 3—Cash and Cash Equivalents

        The Company considers all highly liquid investments with maturities of three months or less on the date of acquisition to be cash equivalents.

Note 4—Natural Gas Derivative Financial Instruments

        The Company, in an effort to manage its natural gas commodity price risk exposures related to certain contracts, utilizes derivative financial instruments. The Company, from time to time, enters into natural gas futures contracts that are over-the-counter swap transactions that convert its index-based gas supply arrangements to fixed-price arrangements. The Company accounts for its derivative instruments in accordance with authoritative guidance for derivative instruments and hedging activities, which requires the recognition of all derivatives as either assets or liabilities in the consolidated balance sheet and the measurement of those instruments at fair value. Historically through June 30, 2008, the Company's derivative instruments have not qualified for hedge accounting under the authoritative guidance. On and after July 1, 2008, the Company entered into futures contracts that did qualify for hedge accounting. The Company's futures contracts at September 30, 2009 are being accounted for as cash flow hedges under the authoritative guidance and are being used to mitigate the Company's exposure to changes in the price of natural gas and not for speculative purposes. At September 30, 2009, all of the Company's futures contracts qualified for hedge accounting.

        The counter-party to the Company's derivative transactions is a high credit quality counterparty; however, the Company is subject to counterparty credit risk to the extent the counterparty to the derivatives is unable to meet its settlement commitments. The Company manages this credit risk by minimizing the number and size of its derivative contracts. The Company actively monitors the creditworthiness of its counterparties and records valuation adjustments against the derivative assets to reflect counterparty risk, if necessary. The counter-party is also exposed to credit risk of the Company, which requires the Company to provide cash deposits as collateral.

        The Company marks to market its open futures positions at the end of each period and records the net unrealized gain or loss during the period in derivative (gains) losses in the consolidated statements of operations or in accumulated other comprehensive income in the condensed consolidated balance sheets in accordance with the guidance. The Company recorded unrealized gains of approximately $1.5 million in accumulated other comprehensive income for the nine month period ended September 30, 2009 related to its futures contracts. The fair value of the Company's futures contracts of approximately $836,000 at September 30, 2009 is included in prepaid expenses and other current assets for the short-term amount ($502,000), and other long-term assets for the long-term amount on the Company's condensed consolidated balance sheet at September 30, 2009. The Company's ineffectiveness related to its futures contracts during the nine month period ended September 30, 2009 was insignificant. For the nine month period ended September 30, 2009, the

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CLEAN ENERGY FUELS CORP. AND SUBSIDIARIES

NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS (Continued)

(Unaudited)

Note 4—Natural Gas Derivative Financial Instruments (Continued)

Company recognized cost of sales of $1.7 million in the accompanying condensed consolidated statement of operations related to its futures contracts that were settled during the nine-month period.

        The Company is required to make certain deposits on its futures contracts, should any exist. At September 30, 2009, the Company had $3.9 million of margin deposits related to its futures contracts covering approximately 31.8 million gasoline gallon equivalents of natural gas fuel, of which $2.6 million related to contracts that expire in the next 12 months and were classified as current at September 30, 2009. The deposits are recorded in prepaid expenses and other current assets and notes receivable and other long-term assets in the accompanying condensed consolidated balance sheet as of September 30, 2009.

        The following table presents the notional amounts and weighted average fixed prices per gasoline gallon equivalent of the Company's natural gas futures contracts as of September 30, 2009:

Note 5—Fixed Price and Price Cap Sales Contracts

        The Company enters into contracts with various customers, primarily municipalities, to sell LNG or CNG at fixed prices, and prior to January 1, 2007, the Company also entered into contracts to sell LNG or CNG at prices subject to a price cap. Effective January 1, 2007, the Company no longer offers contracts with a price cap to its customers. The contracts generally range from two to five years. The most significant cost component of LNG and CNG is the price of natural gas.

        As part of determining the fixed price or price cap in the contracts, the Company works with its customers to determine their future usage over the contract term. However, the Company's fixed price and price cap customers do not agree to purchase a minimum amount of volume or guarantee their volume of purchases. There is not an explicit volume in the contract as the Company agrees to sell its customers volumes on an "as needed" basis, also known as a "requirements contract." The volume required under these contracts varies each month, and is not subject to any minimum commitments. For U.S. generally accepted accounting purposes, there is not a "notional amount," which is one of the required conditions for a transaction to be a derivative pursuant to the authoritative guidance.

        The Company's sales agreements that fix the price or cap the price of LNG or CNG that it sells to its customers are, for accounting purposes, firm commitments, and U.S. generally accepted accounting principles do not require or allow the Company to record a loss until the delivery of the gas and corresponding sale of the product occurs. When the Company enters into these fixed price or price cap contracts with its customers, the price is set based on the prevailing index price of natural gas at that

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CLEAN ENERGY FUELS CORP. AND SUBSIDIARIES

NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS (Continued)

(Unaudited)

Note 5—Fixed Price and Price Cap Sales Contracts (Continued)

time. However, the index price of natural gas constantly changes, and a difference between the fixed price of the natural gas included in the customer's contract price and the corresponding index price of natural gas typically develops after the Company enters into the sales contract (with the price of natural gas having historically increased). From time to time, the Company has also entered into natural gas futures contracts to offset economically the adverse impact of rising natural gas prices (see note 4), and prior to January 1, 2007, if the Company believed the price of natural gas would decline in the future, periodically sold such contracts.

        Historically, from an accounting perspective, during periods of rising natural gas prices, the Company's futures contracts have generally been marked-to-market through the recognition of a derivative asset and a corresponding derivative gain in its statements of operations. However, because the Company's contracts to sell LNG or CNG to its customers at fixed prices or an index-based price that is subject to a fixed price cap are not derivatives for purposes of U.S. generally accepted accounting principles, a liability or a corresponding loss has not been recognized in the Company's statements of operations during these periods of rising natural gas prices for the future commitments under these contracts. As a result, the Company's statements of operations do not reflect its firm commitments to deliver LNG or CNG at prices that are below, and in some cases, substantially below, the prevailing market price of natural gas (and therefore LNG or CNG).

Note 6—Other Receivables

        Other receivables at December 31, 2008 and September 30, 2009 consisted of the following:

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CLEAN ENERGY FUELS CORP. AND SUBSIDIARIES

NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS (Continued)

(Unaudited)

Note 7—Land, Property and Equipment

        Land, property and equipment at December 31, 2008 and September 30, 2009 are summarized as follows:

Note 8—Investments in Other Entities

        Through September 30, 2009, the Company invested approximately $8.6 million in The Vehicle Production Group LLC ("VPG"), a company that is developing a natural gas vehicle made in the United States for taxi and paratransit use. On October 5, 2009, the Company invested an additional $1.4 million in VPG. The Company committed to fund up to $10.0 million in VPG from August 2008 through March 2010, and VPG may under certain circumstances make a capital call on investors which could require the Company to invest up to approximately $0.8 million in additional funds. The Company accounts for its investment in VPG under the cost method of accounting as the Company does not have the ability to exercise significant influence over VPG's operations.

        On August 27, 2008, a subsidiary of the Company converted outstanding commercial loans previously made to Bachman NGV, Inc. ("BAF"), a natural gas vehicle conversion company, into a secured convertible promissory note that was convertible into equity interests in BAF. On October 1, 2009, The Company purchased 100% of BAF for $8.3 million under a stock purchase agreement and retired the note payable outstanding to a subsidiary of the Company at the time (see note 21).

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CLEAN ENERGY FUELS CORP. AND SUBSIDIARIES

NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS (Continued)

(Unaudited)

Note 9—Accrued Liabilities

        Accrued liabilities at December 31, 2008 and September 30, 2009 consisted of the following:

Note 10—Long-term Debt

        In conjunction with the Company's acquisition of its 70% interest in DCE (see note 2), on August 15, 2008, the Company entered into a Credit Agreement with PCB. The Company borrowed $18.0 million (the "Facility A Loan") to finance the acquisition of its membership interests in DCE. The Company also obtained a $12.0 million line of credit from PCB to finance capital improvements of the DCE processing facility and to pay certain costs and expenses related to the acquisition and the PCB loans (the "Facility B Loan"). As of September 30, 2009, the Company had borrowed $12.0 million under the Facility B Loan. On October 7, 2009, the Facility A Loan was repaid in full and converted into a line of credit pursuant to an amendment to the Credit Agreement (see note 21). Interest accrues daily on the amounts outstanding under the Credit Agreement at the greater of the prime rate of interest for the United States plus 0.50% per annum or 5.50% per annum. The principal amount of the Facility B Loans became due and payable in annual payments commencing on August 1, 2009, and continuing each anniversary date thereafter, with each such payment being in an amount equal to the lesser of twenty percent of the aggregate principal amount of the Facility B Loan then outstanding or $2,800,000. On August 15, 2013, the remaining amount of unpaid principal and interest under the Facility B Loans is due and payable. The Company paid a facility fee of $300,000 in connection with the Credit Agreement. As of September 30, 2009, the unamortized balance of the facility fee was $232,500. Amortization of the facility fee is recorded as additional interest expense in the consolidated statements of operations.

        The Credit Agreement requires the Company to comply with certain covenants. The Company may not incur indebtedness or liens except as permitted by the Credit Agreement, or declare or pay dividends. The Company must maintain, on a quarterly basis, minimum liquidity of not less than $6.0 million, accounts receivable balances, as defined, of not less than $8.0 million, consolidated net worth, as defined, of not less than $150.0 million, and a debt to equity ratio, as defined, of not more than 0.3 to 1. Beginning in the quarter ended June 30, 2009, the Company must also maintain a debt service ratio, as defined, of not less than 1.5 to 1 at each quarter end. Effective in the fourth quarter of 2008, the Company established a lock-box arrangement with PCB subject to the Credit Agreement. Funds from the Company's customers are remitted to the lock-box and then deposited to a PCB bank

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NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS (Continued)

(Unaudited)

Note 10—Long-term Debt (Continued)

account. The remitted funds are not used to pay-down the balance of the credit agreement. However, if the Company defaults on the Credit Agreement, all of the obligations under the Credit Agreement will become immediately due and payable and all funds received in the Company's lock-box held by PCB will be applied to the balance due on the Facility A and B Loans. One of the events of default is the occurrence of a "material adverse change," which is a subjective acceleration clause. Based on the authoritative guidance for balance sheet classification of borrowings outstanding under revolving credit agreements that include both a subjective acceleration clause and a lock-box arrangement, the Company has classified its debt pursuant to the Credit Agreement as short-term or long-term as appropriate and believes an event of default is more than remote but not more likely than not. One of the Company's bank covenants is a requirement to maintain accounts receivable balances from certain subsidiaries above $8.0 million at each quarter end during the term. To the extent natural gas prices fall, which a significant portion of the Company's revenues are derived from, or the Company's volumes decline, the Company could violate this covenant in the future. Beginning with the quarter ended June 30, 2009, the Company is required to maintain a debt service ratio, as defined, of not less than 1.5 to 1. To the extent the Company's operating results do not materialize as anticipated, the Company could violate this covenant in the future. In the event the Company would violate either of these covenants, it would seek a waiver from the bank. The Company is in compliance with the covenants as of September 30, 2009. The Credit Agreement is secured by the Company's interest in, and note receivable from, DCE (described below), certain of the Company's accounts receivable and inventory balances and 45 of the Company's LNG tanker trailers. The net book value of the collateral securing the PCB loans was approximately $50.3 million at September 30, 2009. The Company maintains $2.5 million in a payment reserve account at PCB. PCB may withdraw funds from the account to apply to the principal and interest payments due on the new line of credit (see note 21) or the Facility B Loan. Such amount is included as restricted cash in the Company's consolidated balance sheet at September 30, 2009.

        As part of the transaction, the Company also entered into a Loan Agreement with DCE (the "DCE Loan") to provide secured financing of up to $14.0 million to DCE for future capital expenditures or other uses as agreed to by the Company in its sole discretion. As of November 5, 2009, the Company has approximately $8.5 million outstanding under the DCE Loan. Interest on the unpaid balance accrues at a rate of 12% per annum and became payable quarterly beginning on September 30, 2008. The principal amount of the loan is due and payable in annual payments commencing on August 1, 2009, and continuing each anniversary date thereafter, with each such payment being in an amount equal to the lesser of the aggregate principal amount of the DCE Loan then outstanding or $2,800,000. On August 1, 2013, the entire amount of unpaid principal and interest under the DCE Loan is due and payable. The principal and accrued interest balances as well as any interest income related to the DCE Loan are eliminated in the consolidated financial statements of the Company. Any event of default by DCE on the DCE Loan results in a cross-default of the Company's Credit Agreement with PCB. Events of default include failure to make payments when due, DCE's failure to perform under the provisions of its landfill lease with the City of Dallas, DCE's violation of a covenant under its operating agreement and other standard events of default.

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NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS (Continued)

(Unaudited)

Note 10—Long-term Debt (Continued)

        Principal payments for the following periods under the Facility A Loan, which was repaid and converted to a line of credit on October 7, 2009 (see note 21), and the Facility B Loan at September 30, 2009 are as follows:

Note 11—Issuance of Common Stock

        On July 1, 2009, the Company closed a follow-on public offering of 9,430,000 shares of common stock at a price of $8.30 per share. The aggregate amount of common shares sold reflects the exercise in full by the underwriters of their option to purchase 1,230,000 additional shares of the Company's common stock to cover over-allotments. The Company received aggregate net proceeds of approximately $73.2 million, after deducting underwriting discounts and commissions and estimated offering expenses payable by the Company.

        As a result of the follow-on public offering, the exercise price of the Company's Series I Warrants issued on October 28, 2008 was adjusted to $12.68 per share from $13.50 per share per the terms of the Series I warrant agreements.

Note 12—Correction of Immaterial Error

        Subsequent to the year ended December 31, 2008, the Company identified an error in the number of gallons it used to claim its Volumetric Excise Tax Credit ("VETC") refund. Due to this error, the Company's revenues were understated in 2007 and overstated in 2008.

        The Company assessed the materiality of this error for each quarterly and annual period in accordance with Staff Accounting Bulletin No. 99, Materiality, and determined that the error was immaterial to previously reported amounts contained in its periodic reports. Accordingly, the Company has revised its consolidated balance sheet as of December 31, 2008 and it intends to revise its consolidated financial statements for certain quarterly and annual periods through subsequent periodic filings. For quarters prior to June 30, 2008, the Company's financial statements have not been revised as the net amount of the error is insignificant. The effect of recording this immaterial correction in the statements of operations for the year ended December 31, 2008, the balance sheet as of December 31,

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NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS (Continued)

(Unaudited)

Note 12—Correction of Immaterial Error (Continued)

2008, and for the fiscal 2008 quarterly periods to be reported in subsequent periodic filings are as follows:

Note 13—Earnings Per Share

        Basic earnings per share is based upon the weighted average number of shares outstanding during each period. Diluted earnings per share reflects the impact of assumed exercise of dilutive stock options and warrants. The information required to compute basic and diluted earnings per share is as follows:

        Certain securities were excluded from the diluted earnings per share calculations at September 30, 2008 and 2009, respectively, as the inclusion of the securities would be anti-dilutive to the calculation. The amounts outstanding as of September 30, 2008 and 2009 for these instruments are as follows:

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NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS (Continued)

(Unaudited)

Note 14—Comprehensive Income (Loss)

        The following table presents the Company's comprehensive loss for the nine months ended September 30, 2008 and 2009:

Note 15—Stock-Based Compensation

        The following table summarizes the compensation expense and related income tax benefit related to stock-based compensation expense recognized during the periods:

Stock Options

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NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS (Continued)

(Unaudited)

Note 15—Stock-Based Compensation (Continued)

        The following table summarizes the Company's stock option activity during the nine months ended September 30, 2009:

        The fair value of each option is estimated on the date of grant using the Black-Scholes option pricing model with the following weighted average assumptions used for grants in 2009:

        Based on these assumptions, the weighted average grant date fair value of options granted during the nine months ended September 30, 2009 was $4.37.

Note 16—Use of Estimates

        The preparation of consolidated financial statements in conformity with U.S. generally accepted accounting principles requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and the disclosure of contingent assets and liabilities at the date of the consolidated financial statements and revenues and expenses during the reporting period. Actual results could differ from those estimates.

Note 17—Environmental Matters, Litigation, Claims, Commitments and Contingencies

        The Company is subject to federal, state, local, and foreign environmental laws and regulations. The Company does not anticipate any expenditures to comply with such laws and regulations which would have a material impact on the Company's consolidated financial position, results of operations, or liquidity. The Company believes that its operations comply, in all material respects, with applicable federal, state, local and foreign environmental laws and regulations.

        The Company has been and may become party to various legal actions that arise in the ordinary course of its business. During the course of its operations, the Company has been, currently is and may become subject to audit by tax authorities for varying periods in various federal, state, local, and foreign tax jurisdictions. Disputes may arise during the course of such audits as to facts and matters of law. It is impossible at this time to determine the ultimate liabilities that the Company may incur resulting from any lawsuits, claims and proceedings, audits, commitments, contingencies and related matters or the timing of these liabilities, if any. If these matters were to be ultimately resolved unfavorably, an outcome not currently anticipated, it is possible that such outcome could have a material adverse effect upon the Company's consolidated financial position or results of operations. However, the Company believes that the ultimate resolution of such actions will not have a material adverse affect on the Company's consolidated financial position, results of operations, or liquidity.

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NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS (Continued)

(Unaudited)

Note 18—Income Taxes

        The Company is required to recognize the impact of a tax position in its financial statements if the position is more likely than not of being sustained by the taxing authority upon examination, based on the technical merits of the position. The Company accrues interest based on the difference between a tax position recognized in the financial statements and the amount claimed on its returns at statutory interest rates. The net interest incurred was immaterial for the nine months ended September 30, 2008 and 2009. Further, the Company accrues penalties if the tax position does not meet the minimum statutory threshold to avoid penalties. No penalties have been accrued by the Company. The Company's unrecognized tax benefits as of September 30, 2009 are unchanged from December 31, 2008. It is anticipated that the Company's liability for uncertain tax positions will be reduced by as much as $387,000 during the year as a result of the settlement of tax positions with various tax authorities.

        The Company is subject to taxation in the United States and various states and foreign jurisdictions. The Company's tax years for 2005 through 2008 are subject to examination by various tax authorities. The Company is no longer subject to U.S. examination for years before 2006, and state examinations for years before 2005. The Company is currently under audit by the Internal Revenue Service for tax years 2005 through 2007.

Note 19—Fair Value Measurements

        On January 1, 2008, the Company adopted the authoritative guidance for fair value measurements which defines fair value, establishes a framework for measuring fair value and enhances disclosures about fair value measurements related to financial instruments. In December 2007, the Financial Accounting Standard Board ("FASB") provided a one-year deferral of this guidance for non-financial assets and non-financial liabilities, except those that are recognized or disclosed at fair value on a recurring basis, at least annually. Accordingly, the Company adopted this guidance for non-financial assets and non-financial liabilities on January 1, 2009.

        During the nine months ended September 30, 2009, the Company's financial instruments consisted of natural gas futures contracts, debt instruments, and its Series I warrants (see note 11). The Company uses quoted forward price curves, discounted to reflect the time value of money, to value its natural gas futures contracts. The Company uses a Monte Carlo simulation model to value the Series I warrants, which requires the Company to make certain estimates including risk-free interest rates and the volatility of its stock price, among others. The Company's futures contracts are recorded in prepaid expenses and other current assets for the current amount, and long-term assets for the long-term amount, and the Series I warrants are recorded in other long-term liabilities in the accompanying condensed consolidated balance sheet at September 30, 2009. The fair market value of the Company's debt instruments approximated their carrying values at September 30, 2009.

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CLEAN ENERGY FUELS CORP. AND SUBSIDIARIES

NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS (Continued)

(Unaudited)

Note 19—Fair Value Measurements (Continued)

        The following table reflects the fair value as defined by the authoritative guidance of the Company's natural gas futures contracts and Series I warrants at September 30, 2009:

Note 20—Recently Adopted Accounting Changes and Recently Issued Accounting Standards

        In December 2007, the FASB revised it existing guidance on business combinations by providing new accounting guidance and disclosure requirements for business combinations. The revised guidance is effective for business combinations which occur beginning in 2009. The adoption of this revised guidance did not have a material impact on the Company's financial statements.

        In December 2007, the FASB issued new authoritative guidance for Noncontrolling Interests in Consolidated Financial Statements. This new guidance requires presentation of non-controlling interests in consolidated subsidiaries separately within equity in the consolidated statements of financial position as well as the separate presentation within the consolidated statements of operations and comprehensive income (loss) attributable to the parent and noncontrolling interest. Accounting for changes in a parent's ownership interest will generally be at fair value, and if the parent retains control or significant influence of the subsidiary, any adjustments will be made through equity, while transactions where control changes occur will be accounted for through earnings. This new authoritative guidance was effective for the Company on January 1, 2009. As a result of adopting this guidance, the Company reclassified the minority interest of DCE to the stockholders' equity section of its consolidated balance sheet. References to minority interest in previous financial statements are now reflected as noncontrolling interest. The adoption of this statement did not have a material impact on the Company's consolidated financial position or results of operations.

        In March 2008, the FASB issued new authoritative guidance on disclosures about derivative instruments and hedging activities. This guidance requires enhanced disclosures about the Company's derivative and hedging activities. The Company is required to provide enhanced disclosures about (a) how and why it uses derivative instruments, (b) how derivative instruments and related hedged items are accounted for, and (c) how derivative instruments and related hedged items affect the Company's financial position, results of operations, and cash flows. The Company adopted this guidance as of January 1, 2009 and the adoption did not have a material impact on its consolidated financial statements.

        In April 2008, the FASB issued its position on determination of the useful life of intangible assets by amending the factors that should be considered in developing renewal or extension assumptions used to determine the useful life of a recognized intangible asset. Specifically, the FASB removed the requirement to consider whether an intangible asset can be renewed without substantial cost or material modifications to the existing terms and conditions, and instead, requires an entity to consider its own historical experience in renewing similar arrangements. The FASB also now requires expanded disclosure related to the determination of intangible asset useful lives. This requirement was effective

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CLEAN ENERGY FUELS CORP. AND SUBSIDIARIES

NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS (Continued)

(Unaudited)

Note 20—Recently Adopted Accounting Changes and Recently Issued Accounting Standards (Continued)

for the Company on January 1, 2009. Adoption of this guidance did not have a material impact on the Company's consolidated financial statements.

        In June 2008, FASB reached a consensus on determining whether an instrument (or embedded feature) is indexed to an entity's own stock. The FASB concluded, among other things, that contingent and other adjustment features in equity-linked financial instruments are consistent with equity indexation if they are based on variables that would be inputs to a "plain vanilla" option or forward pricing model and they do not increase the contract's exposure to those variables. The Company's Series I warrants issued on October 28, 2008 are linked to the Company's own equity shares; however, the investor has protective pricing features commonly referred to as "down-round" protection, whereby the conversion price potentially resets if the common stock price of the Company declines after issuance. As a result of this guidance, effective January 1, 2009, the Company accounts for the Series I warrants as a derivative. The Company recorded a cumulative-effect adjustment of approximately $2.6 million to opening retained earnings and reclassed approximately $9.8 million from additional paid-in capital to long-term liabilities on the date of adopting this guidance, January 1, 2009. During the first nine months 2009, the Company recorded charges of $17.8 million related to valuing the Series I warrants.

        In April 2009, the FASB issued new authoritative guidance on determining fair value when the volume and level of activity for the asset or liability have significantly decreased. The guidance provides that when the volume and level of activity for the asset or liability have significantly decreased, that regardless of market conditions, the fair value measurement is an exit price concept. This guidance clarifies and includes additional factors to consider in determining whether there has been a significant decrease in market activity for an asset or liability and provides additional clarification on estimating fair value when the market activity for an asset or liability has declined significantly. The scope of this guidance does not include assets and liabilities measured under Level 1 inputs. The Company adopted this guidance on April 1, 2009 and its adoption did not have a material impact on the Company's consolidated financial statements.

        In May 2009, the FASB issued new authoritative guidance on reporting subsequent events, which establishes general standards of accounting for and disclosures of events that occur after the balance sheet date, but before the financial statements are issued or are available to be issued. This guidance requires the disclosure of the date through which an entity has evaluated subsequent events, and is effective for interim and annual reporting periods ending after June 15, 2009. The Company adopted the new disclosure requirements on April 1, 2009 and its adoption did not have a material impact on the Company's consolidated financial statements.

        On June 30, 2009, the FASB issued new authoritative guidance on interim disclosures about fair value of financial instruments. This guidance requires publicly-traded companies to provide disclosures on the fair value of financial instruments in interim financial statements. The Company adopted the new disclosure requirements on April 1, 2009 and its adoption did not have a material impact on the Company's consolidated financial statements.

        In July 2009, the FASB codified the accounting standards ("Codification"). The Codification will become the source of authoritative U.S. generally accepted accounting principles ("GAAP") recognized

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CLEAN ENERGY FUELS CORP. AND SUBSIDIARIES

NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS (Continued)

(Unaudited)

Note 20—Recently Adopted Accounting Changes and Recently Issued Accounting Standards (Continued)

by the FASB to be applied by nongovernmental entities. Rules and interpretive releases of the SEC under authority of federal securities laws are also sources of authoritative GAAP for SEC registrants. On the effective date of this Statement, the Codification will supersede all then-existing, non-SEC accounting and reporting standards. All other nongrandfathered, non-SEC accounting literature not included in the Codification will become nonauthoritative. This Statement is effective for the Company's consolidated financial statements issued for interim and annual periods ending after September 15, 2009. The Company adopted this guidance September 30, 2009 and its adoption did not have a material impact on the Company's consolidated financial statements.

        In September 2009, the FASB issued new authoritative guidance on earnings per share calculations. This guidance requires the difference between the fair value of the consideration transferred to the holders for the redemption or conversion of preferred stock and the carrying amount of the preferred stock be subtracted from or added to net income to arrive at income available to common share in the calculation of earnings per share. The Company does not anticipate the adoption of this guidance will have a material impact on its consolidated financial statements.

        In October 2009, the FASB issued new authoritative guidance on multi-deliverable revenue arrangements. This guidance establishes requirements that must be met for an entity to recognize revenue from the sale of a delivered item that is part of a multiple-element arrangement when other items have not yet been delivered. One of those current requirements is that there be objective and reliable evidence of the standalone selling price of the undelivered items, which must be supported by either vendor-specific objective evidence ("VSOE") or third-party evidence ("TPE"). This guidance amends previous guidance by eliminating the requirement that all undelivered elements have VSOE or TPE before an entity can recognize the portion of an overall arrangement fee that is attributable to items that already have been delivered. In the absence of VSOE or TPE of the standalone selling price for one or more delivered or undelivered elements in a multiple-element arrangement, entities will be required to estimate the selling prices of those elements. The overall arrangement fee will be allocated to each element (both delivered and undelivered items) based on their relative selling prices, regardless of whether those selling prices are evidenced by VSOE or TPE or are based on the entity's estimated selling price. Application of the "residual method" of allocating an overall arrangement fee between delivered and undelivered elements will no longer be permitted under this new guidance. Additionally, the new guidance will require entities to disclose more information about their multiple-element revenue arrangements. This guidance is effective June 15, 2010 and the Company is currently evaluating the impact of this guidance on is consolidated financial statements.

Note 21—Subsequent Events

        On October 1, 2009, the Company purchased all the outstanding shares of BAF Technologies, Inc. ("BAF") under a stock purchase agreement. The purchase price for the acquisition of BAF was approximately $8.3 million. Pursuant to the terms of the agreement, the purchase price was reduced by the amount of BAF's outstanding debt which was repaid in full at closing. Due to the fact that approximately $3.8 million of BAF's outstanding debt was held by Clean Energy Finance, a wholly-owned Clean Energy subsidiary, Clean Energy paid a net amount of approximately $4.5 million in cash to acquire BAF at the closing. BAF shareholders will be able to earn additional consideration if

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CLEAN ENERGY FUELS CORP. AND SUBSIDIARIES

NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS (Continued)

(Unaudited)

Note 21—Subsequent Events (Continued)

BAF achieves certain gross profit targets in fiscal 2010 and 2011. The additional consideration will be determined as a percentage of gross profit based on a sliding scale that increases at certain gross profit levels, subject to achieving a minimum gross profit target and capped by a maximum additional payment amount. For 2010, the shareholders of BAF will receive between one and twenty-six percent of gross profit of BAF as additional consideration if BAF achieves $8 million or more in gross profit, up to a maximum of $11 million in additional consideration (which would be payable if BAF achieved approximately $42.3 million in gross profit in 2010). For 2011, the shareholders of BAF will receive between one and twenty-one percent of gross profit of BAF as additional consideration if BAF achieves $8.5 million or more in gross profit, up to a maximum of $11 million in additional consideration (which would be payable if BAF achieved approximately $52.4 million in gross profit in 2011).

        On October 7, 2009, the Company repaid in full its Facility A loan (approximately $17.1 million outstanding at the time) and simultaneously amended its Credit Agreement to obtain a line of credit ("LOC") from PlansCapital Bank. The LOC expires August 15, 2011, which includes a one year renewal option available to the Company, and the Company can draw up to $20 million over this period. The Company can use the proceeds for capital expenditures, working capital for its operations and for other general corporate purposes.

        On October 9, 2009, the Company issued a total of approximately 1.3 million stock options to its employees and directors at an exercise price of $14.06 per share. The options vest 34% on the first anniversary of the grant date, and 33% on each of the next two anniversaries of the grant date, and were valued at $9.41 per option.

Note 22—Volumetric Excise Tax Credit (VETC)

        The Company records its VETC credits as revenue in its condensed consolidated statements of operations as the credits are fully refundable and do not need to offset income tax liabilities to be received. VETC revenues for the nine month periods ended September 30, 2008 and 2009 were approximately $13.2 million and $11.8 million, respectively.

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Item 2.    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 "MD&A") should be read together with the unaudited condensed consolidated financial statements and the related notes included elsewhere in this report. For additional context with which to understand our financial condition and results of operations, refer to the MD&A for the fiscal year ended December 31, 2008 contained in our 2008 Annual Report on Form 10-K, as well as the consolidated financial statements and notes contained therein.

Cautionary Statement Regarding Forward Looking Statements

        This MD&A and other sections of this report contain forward looking statements. We make forward-looking statements, as defined by the "safe harbor" provisions of the Private Securities Litigation Reform Act of 1995, and in some cases, you can identify these statements by forward-looking words such as "if," "shall," "may," "might," "will likely result," "should," "expect," "plan," "anticipate," "believe," "estimate," "project," "intend," "goal," "objective," "predict," "potential" or "continue," or the negative of these terms and other comparable terminology. These forward-looking statements, which are based on various underlying assumptions and expectations and are subject to risks, uncertainties and other unknown factors, may include projections of our future financial performance based on our growth strategies and anticipated trends in our business. These statements are only predictions based on our current expectations and projections about future events that we believe to be reasonable. There are important factors that could cause our actual results, level of activity, performance or achievements to differ materially from the historical or future results, level of activity, performance or achievements expressed or implied by such forward-looking statements. These factors include, but are not limited to, those discussed under the caption "Risk Factors" in this report and in our 2008 Annual Report on Form 10-K. In preparing this MD&A, we presume that readers have access to and have read the MD&A in our 2008 Annual Report on Form 10-K pursuant to Instruction 2 to paragraph (b) of Item 303 of Regulation S-K. We undertake no duty to update any of these forward- looking statements after the date of filing of this report to conform such forward-looking statements to actual results or revised expectations, except as otherwise required by law.

Overview

        We provide natural gas solutions for vehicle fleets primarily in the United States and Canada. Our primary business activity is selling compressed natural gas ("CNG") and liquified natural gas ("LNG") vehicle fuel to our customers. We also build, operate and maintain fueling stations, and help our customers acquire and finance natural gas vehicles and obtain local, state and federal clean air incentives. Our customers include fleet operators in a variety of markets, such as public transit, refuse hauling, airports, taxis and regional trucking. In April 2008, we opened our first compressed natural gas station in Lima, Peru, through our joint venture, Clean Energy del Peru. In August 2008, we acquired 70% of the outstanding membership interest of Dallas Clean Energy, LLC ("DCE"). DCE owns a facility that collects, processes and sells renewable biomethane collected from a landfill in Dallas, Texas. On October 1, 2009, the Company acquired 100% of BAF Technologies, Inc., a company that provides natural gas conversions, alternative fuel systems, application engineering, service and warranty support and research and development for natural gas vehicles.

        The following overview discusses matters on which our management focuses in evaluating our financial condition and operating performance as well as recent and anticipated business trends.

        Sources of revenue.    We generate the majority of our revenue from selling CNG and LNG and providing operations and maintenance services to our customers. The balance of our revenue is provided by designing and constructing natural gas fueling stations, financing our customers' natural gas vehicle purchases and sales of pipeline quality biomethane produced by our DCE joint venture.

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        Key operating data.    In evaluating our operating performance, our management focuses primarily on: (1) the amount of CNG and LNG gasoline gallon equivalents delivered (which we define as (i) the volume of gasoline gallon equivalents we sell to our customers, plus (ii) the volume of gasoline gallon equivalents dispensed to our customers at stations where we provide operating and maintenance ("O&M") services but do not directly sell the CNG or LNG, plus (iii) our proportionate share of the gasoline gallon equivalents sold as CNG by our joint venture in Peru, plus (iv) our proportionate share of the gasoline gallon equivalents of biomethane produced and sold as pipeline quality natural gas by DCE); (2) our revenue; and (3) net income (loss). The following table, which you should read in conjunction with our condensed consolidated financial statements and notes contained elsewhere in this report, presents our key operating data for the years ended December 31, 2006, 2007 and 2008 and for the three and nine months ended September 30, 2008 and 2009:

        Key trends in 2006, 2007, and 2008 and the first nine months of 2009.    Vehicle fleet demand for natural gas fuels increased during the three year and nine-month period ended September 30, 2009 based on gasoline gallon equivalents delivered. We believe this growth in demand was attributable primarily to the rising prices of gasoline and diesel relative to CNG and LNG during this period and increasingly stringent environmental regulations affecting vehicle fleets. We capitalized on this growing demand by securing new fleet customers in a variety of markets, including public transit, refuse hauling, airports, taxis and regional trucking.

        The number of fueling stations we served grew from 147 at December 31, 2004 to 195 at September 30, 2009 (a 32.7% increase). The amount of CNG and LNG gasoline gallon equivalents we delivered from 2006 to 2008 increased by 7.5%. Our gasoline gallon equivalents delivered during the first nine months of 2009 as compared to the first nine months of 2008 increased 30.5%. The increase in gasoline gallon equivalents delivered, together with higher prices we charged our customers due to higher natural gas prices, contributed to increased revenues from 2006 through the end of 2008. During the first nine months of 2009, our revenues declined as compared to the first nine months of 2008 primarily due to lower natural gas prices offset by the increase in gasoline gallon equivalents delivered and serviced. Our cost of sales also increased from 2006 through the end of 2008, which was attributable primarily to the increased costs related to delivering more CNG and LNG to our customers and the increased price of natural gas. Our cost of sales decreased during the first nine months of 2009 as compared to the first nine months of 2008 primarily due to lower natural gas prices offset by the increased costs related to delivering and servicing more CNG and LNG to our customers.

        Recent developments.    On October 1, 2009, we purchased all of the outstanding shares of BAF Technologies, Inc. ("BAF") under a Stock Purchase Agreement. The purchase price for the acquisition of BAF was approximately $8.3 million. Pursuant to the terms of the Stock Purchase Agreement, the purchase price was reduced by the amount of BAF's outstanding debt which was repaid in full at closing. Due to the fact that approximately $3.8 million of BAF's outstanding debt was held by Clean Energy Finance, a wholly owned Clean Energy subsidiary, we paid a net amount of approximately $4.5 million in cash to acquire BAF. BAF shareholders will be able to earn additional consideration if

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BAF achieves certain gross profit targets in fiscal 2010 and 2011. The additional consideration will be determined as a percentage of gross profit based on a sliding scale that increases at certain gross profit levels, subject to achieving a minimum gross profit target and capped by a maximum additional payment amount. For 2010, the shareholders of BAF will receive between one and twenty-six percent of gross profit of BAF as additional consideration if BAF achieves $8 million or more in gross profit, up to a maximum of $11 million in additional consideration (which would be payable if BAF achieved approximately $42.3 million in gross profit in 2010). For 2011, the shareholders of BAF will receive between one and twenty-one percent of gross profit of BAF as additional consideration if BAF achieves $8.5 million or more in gross profit, up to a maximum of $11 million in additional consideration (which would be payable if BAF achieved approximately $52.4 million in gross profit in 2011).

        Founded in 1992, BAF provides natural gas vehicle conversions, alternative fuel systems, application engineering, service and warranty support and research and development for natural gas vehicles. BAF's vehicle conversions include taxis, limousines, vans, pick-up trucks and shuttle buses. BAF has certified NGVs under both Environmental Protection Agency ("EPA") and California Air Resources Board ("CARB") standards achieving Super Ultra Low Emission Vehicle ("SULEV") emissions. Following AT&T's announcement in March of their intent to deploy more than 15,000 alternative-fuel vehicles over the next five years, approximately 8,000 of which are expected to be NGVs, BAF was awarded a purchase order to provide to AT&T the initial 600 Ford E-Series converted CNG vans.

        Anticipated future trends.    Despite the recent volatility and decline in energy prices, we anticipate that, over the long term, the prices for gasoline and diesel will continue to be higher than the price of natural gas as a vehicle fuel, and more stringent emissions requirements will continue to make natural gas vehicles an attractive alternative to traditional gasoline and diesel powered vehicles. Our belief that natural gas will continue, over the long term, to be a cheaper vehicle fuel than gasoline or diesel is based in part on the growth in U.S. natural gas production. A 2008 Navigant Consulting, Inc. study indicates that as a result of new unconventional gas shale discoveries from 22 basins in the U.S., maximum estimates of total recoverable domestic reserves from producers have increased to equal 118 years of U.S. production at 2007 producing rates. The study indicated a mean level of reserves equal to 88 years of supply at 2007 production levels. Indications were that shale gas production growth from only the major six shale plays, plus the Marcellus shale, could become 27 billion cubic feet per day and as high as 39 billion cubic feet per day by 2015. Navigant has also indicated that development of the shale resources base has resulted in a substantial current surplus of gas supply compared to demand of as much as 11 billion cubic feet per day. These current surplus levels are 18% of annual average historical U.S. consumption levels of approximately 20 Tcf per year making available gas supply to meet all existing markets and to meet new market requirements. Based on analyst reports, we believe that there is a significant worldwide supply of natural gas relative to crude oil as well. According to the 2008 BP Statistical Review of World Energy, on a global basis, the ratio of proven natural gas reserves to 2007 natural gas production was 45% greater than the ratio of proven crude oil reserves to 2007 crude oil production. This analysis suggests significantly greater longer term availability of natural gas than crude oil based on current consumption.

        We believe there will be significant growth in the consumption of natural gas as a vehicle fuel among vehicle fleets, and our goal is to capitalize on this trend and enhance our leadership position as this market expands. We have built natural gas fueling stations, and plan to build additional natural gas fueling stations, that will provide LNG to fleet vehicles at the Ports of Los Angeles and Long Beach. We also anticipate expanding our sales of CNG and LNG in the other markets in which we operate, including public transit, regional trucking, refuse hauling and airports. Consistent with the anticipated growth of our business, we also expect that our operating costs and capital expenditures will increase, primarily from the anticipated expansion of our station network as well as the logistics of delivering more CNG and LNG to our customers. Additionally, we have and will continue to increase our sales

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and marketing team and other necessary personnel as we seek to expand our existing markets and enter new markets, which will also result in increased costs.

        The disruption in the capital markets that began during 2008 and has continued into 2009 has made it more difficult for new customers to finance or invest in natural gas vehicle acquisitions or natural gas fueling stations. Continuing economic contraction and reduced economic activity may reduce our opportunities to attract new fleet customers. Many governmental entities, which during 2006 through 2008 represented approximately two-thirds of our revenues, are experiencing significant budget deficits as a result of the economic recession and have been and may continue to be unable to invest in new natural gas vehicles for their transit or refuse fleets or may be compelled to reduce public transportation and services, which would negatively affect our business.

        Planned capital expenditures and other capital requirements.    Our current business plan calls for approximately $5.9 million in additional capital expenditures from October 1, 2009 through the end of 2009, primarily related to construction of new fueling stations. In addition, we anticipate that from October 1, 2009 through the end of 2009 we will provide approximately $0.2 million for financing natural gas vehicle purchases by our customers and up to $2.2 million in funding ($1.4 million of which was funded by us on October 5, 2009) that we may be required to provide to the Vehicle Production Group, LLC, a company that is developing CNG paratransit vehicles and taxis. We anticipate that during the remainder of 2009 we will provide any further funds requested by DCE pursuant to our loan agreement with DCE through our available cash reserves. We may also elect to invest additional amounts that are not budgeted for in our 2009 business plan in station construction for new or existing customers that are not currently under contract or for acquisitions or investments in companies or assets in the natural gas and biomethane fueling infrastructure, services and production industries. We intend to fund our principal liquidity requirements through cash and cash equivalents and cash provided by operations. For more information, see "Liquidity and Capital Resources" below.

        Volatility in operating results related to futures contracts.    Historically, we have purchased futures contracts from time to time to help mitigate our exposure to natural gas price fluctuations in current periods and in future periods. Prior to 2008, our futures contracts did not qualify for hedge accounting under the applicable derivative accounting guidance, and in 2008, some of our contracts qualified for hedge accounting under the accounting guidance and some did not. In 2009, all of our futures contracts did qualify for hedge accounting under the accounting guidance. Gains and losses related to the futures contracts that did not qualify for hedge accounting, which appear in the line item derivative (gains) losses in our condensed consolidated financial statements, have materially impacted our results of operations in recent periods. For the years ended December 31, 2006, 2007 and 2008, derivative (gains) losses associated with futures contracts were $78,994,947, $0 and $611,175, respectively. For this reason and others, we caution investors that our past operating results may not be indicative of future results. For more information, please read "Volatility of Earnings and Cash Flows" and "Risk Management Activities" below.

        Volatility in operating results related to Series I warrants.    Beginning January 1, 2009, under new accounting guidance, we are required to record the change in the fair market value of our Series I warrants in our financial statements. We recognized an expense of $0.2 million, $2.2 million and $15.4 million related to recording the fair market value changes of our Series I warrants in the quarters ended March 31, 2009, June 30, 2009 and September 30, 2009, respectively (see note 20 to our condensed consolidated financial statements contained elsewhere herein). To the extent that our stock price appreciates in future periods that the Series I warrants are outstanding, we may be required to recognize additional expense in those periods which may materially impact our results of operations. If our stock price decreases in future periods that our Series I warrants are outstanding, we may be required to recognize gains in those periods which may materially impact our results of operations.

        Business risks and uncertainties.    Our business and prospects are exposed to numerous risks and uncertainties. For more information, see "Risk Factors" in Part II, Item 1A of this report.

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Operations

        We generate revenues principally by selling CNG and LNG and providing operations and maintenance services to our vehicle fleet customers. For the nine months ended September 30, 2009, CNG and biomethane (together) represented 74% and LNG represented 26% of our natural gas sales (on a gasoline gallon equivalent basis). To a lesser extent, we generate revenues by designing and constructing fueling stations and selling or leasing those stations to our customers. Substantially all of our operating and maintenance revenues are generated from CNG stations, as owners of LNG stations tend to operate and maintain their own stations. Substantially all of our station sale and leasing revenues have been generated from CNG stations. In 2006, we began providing vehicle finance services to our customers.

CNG Sales

        We sell CNG through fueling stations located on our customers' properties and through our network of public access fueling stations. At these CNG fueling stations, we procure natural gas from local utilities or brokers under standard, floating-rate arrangements and then compress and dispense it into our customers' vehicles. Our CNG sales are made primarily through contracts with our fleet customers. Under these contracts, pricing is determined primarily on an index-plus basis, which is calculated by adding a margin to the local index or utility price for natural gas. CNG sales revenues based on an index-plus methodology increase or decrease as a result of an increase or decrease in the price of natural gas. We sell a small amount of CNG under fixed-price contracts and also provide price caps to certain customers on their index-plus pricing arrangements. Effective January 1, 2007, we ceased offering price-cap contracts to our customers, but we will continue to perform our obligations under price-cap contracts we entered into before January 1, 2007. We will continue to offer fixed price contracts as appropriate and consistent with our natural gas hedging policy that was revised in May 2008. Our fleet customers typically are billed monthly based on the volume of CNG sold at a station. The remainder of our CNG sales are on a per fill-up basis at prices we set at the pump based on prevailing market conditions. These customers typically pay using a credit card at the station. In April 2008, we opened our first CNG station in Lima, Peru through our joint venture Clean Energy del Peru.

LNG Sales

        We sell substantially all of our LNG to fleet customers, who typically own and operate their fueling stations. We also sell a small volume of LNG to customers for non-vehicle use. We procure LNG from third-party producers and also produce LNG at our liquefaction plants in Texas and California. For LNG that we purchase from third-parties, we may enter into "take or pay" contracts that require us to purchase minimum volumes of LNG at index-based rates. We deliver LNG via our fleet of 58 tanker trailers to fueling stations, where it is stored and dispensed in liquid form into vehicles. We sell LNG principally through supply contracts that are priced on either a fixed-price or index-plus basis. LNG sales revenues based on an index-plus methodology increase or decrease as a result of an increase or decrease in the price of natural gas. We also provided price caps to certain customers on the index component of their index-plus pricing arrangement for certain contracts we entered into on or prior to December 31, 2006. Effective January 1, 2007, we ceased offering price-cap contracts to our customers, but we will continue to perform our obligations under price-cap contracts we entered into before January 1, 2007, including a one-year renewal period beginning April 1, 2010 that one of our customers is entitled to exercise. This renewal period, if exercised, would obligate us to sell the customer approximately 2.1 million LNG gallons subject to a price cap of $7.50 per MMbtu on the Southern California Gas Company Index. We will continue to offer fixed price contracts as appropriate and consistent with our natural gas hedging policy adopted in May 2008. Our LNG contracts provide that we charge our customers periodically based on the volume of LNG supplied.

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Government Incentives

        From October 1, 2006 through December 31, 2009, we may receive a VETC of $0.50 per gasoline gallon equivalent of CNG and $0.50 per liquid gallon of LNG that we sell as vehicle fuel. Based on the service relationship we have with our customers, either we or our customers are able to claim the credit. We record these tax credits as revenues in our condensed consolidated statements of operations as the credits are fully refundable and do not need to offset tax liabilities to be received. As such, the credits are not deemed income tax credits under the accounting guidance applicable to income taxes. In addition, we believe the credits are properly recorded as revenue because we often incorporate the tax credits into our pricing with our customers, thereby lowering the actual price per gallon we charge them. We expect the tax credit will continue to factor into the price we charge our customers for CNG and LNG in the future. The legislation that created this tax credit also increased the federal excise taxes on sales of CNG from $0.061 to $0.183 per gasoline gallon equivalent and on sales of LNG from $0.119 to $0.243 per LNG gallon.

Operation and Maintenance

        We generate a portion of our revenue from operation and maintenance agreements for CNG fueling stations where we do not supply the fuel. We refer to this portion of our business as "O&M." At these fueling stations, the customer contracts directly with a local broker or utility to purchase natural gas. For O&M services, we do not sell the fuel itself, but generally charge a per-gallon fee based on the volume of fuel dispensed at the station. We include the volume of fuel dispensed at the stations at which we provide O&M services in our calculation of aggregate gallon equivalents sold.

Station Construction

        We generate a small portion of our revenue from designing and constructing fueling stations and selling or leasing the stations to our customers. For these projects, we act as general contractor or supervise qualified third-party contractors. We charge construction fees or lease rates based on the size and complexity of the project.

Vehicle Acquisition and Finance

        In 2006, we commenced offering vehicle finance services for some of our customers' purchases of natural gas vehicles or the conversion of their existing gasoline or diesel powered vehicles to operate on natural gas. We loan to certain qualifying customers on average 60%, and on occasion up to 100%, of the purchase price of their natural gas vehicles. We may also lease vehicles in the future. Where appropriate, we apply for and receive state and federal incentives associated with natural gas vehicle purchases and pass these benefits through to our customers. We may also secure vehicles to place with customers or pay deposits with respect to such vehicles prior to receiving a firm order from our customers, which we may be required to purchase if our customer fails to purchase the vehicle as anticipated. Through September 30, 2009, we have not generated significant revenue from vehicle finance activities.

Landfill Gas

        In August 2008, we acquired 70% of the outstanding membership interests of DCE for a purchase price of $19.6 million including transaction costs. DCE owns a facility that collects, processes and sells biomethane from the McCommas Bluff landfill located in Dallas, Texas. From the acquisition date through December 31, 2008 and for the nine months ended September 30, 2009, DCE generated approximately $1.8 million and $5.1 million, respectively, in revenue from sales of biomethane, all of which is included in our condensed consolidated statements of operations.

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        On April 3, 2009, DCE entered into a fifteen year gas sale agreement with Shell Energy North America (US), L.P. ("Shell") for the sale by DCE to Shell of biomethane produced by DCE's landfill gas processing facility. The gas sale agreement calls for the sale of up to the following quantity of biomethane by DCE to Shell daily:

April 2009 through September 2010: 4500 MMBtus per day
October 2010 through December 2010: 5200 MMBtus per day
Calendar year 2011: 5300 MMBtus per day
Calendar year 2012: 5400 MMBtus per day
Calendar year 2013: 5300 MMBtus per day
Calendar year 2014: 5300 MMBtus per day
Calendar year 2015-2018: 5000 MMBtus per day
Calendar year 2019 to March 2024: 6000 MMBtus per day

        DCE's obligation and ability to sell greater than 4500 MMBtus per day is contingent on the successful permitting and commencement of commercial operation of an expansion to the existing gas processing facility. DCE retains the right to reserve from the gas sale agreement up to 500 MMBtus per day of biomethane for sale as a vehicle fuel. To the extent that DCE produces volumes of biomethane in excess of the volumes sold under the agreement with Shell, DCE will either attempt to sell such volumes at then-prevailing market prices or seek to enter into another gas sale agreement in the future. There is no guarantee that DCE will produce or be able to sell up to the maximum volumes called for under the agreement, and DCE's ability to produce such volumes of biomethane is dependent on a number of factors beyond DCE's control including, but not limited to, the availability and composition of the landfill gas that is collected, the impact on DCE's operations of the operation of the landfill by the City of Dallas and the reliability of the processing plant's critical equipment.

        The sale price for the gas under the agreement with Shell is fixed and increases in 2010 and 2011. The sale price for the gas represents a substantial premium to the current prevailing prices for natural gas at November 9, 2009.

        Under the terms of the agreement, DCE has retained the rights to any available greenhouse gas emission reduction credits that may be generated through the operation of the landfill gas collection and processing facility, provided that DCE must supply Shell with a sufficient number of such credits to enable the end-user of the gas to meet applicable "net-zero" emissions requirements under the relevant renewable portfolio standard with respect to use of the biomethane in power generation. DCE is in the preliminary stages of assessing whether greenhouse gas emission reduction credits will be generated or available for sale as a result of the landfill gas collection and pipeline quality biomethane production. Given the complex and changing standards and requirements in the market for greenhouse gas emission reduction credits, there can be no guarantee that any greenhouse gas emission credits will be generated or available for sale as a result of DCE's landfill gas operations.

        The gas sale agreement is terminable by either party on 30 days' written notice if the California Energy Commission makes a written determination or adopts a ruling or regulation after the date of the agreement that the biomethane sold under the agreement will, from the date of such ruling or regulation, no longer qualify as a California Renewable Portfolio Standard eligible fuel. In addition, Shell has the right to terminate the agreement upon 30 days' written notice if the volumes of biomethane produced and delivered, calculated monthly on a rolling two-year average, are less than an annual average of 630,720 MMBtu per year (or 2,083 MMBtu per day).

Volatility of Earnings and Cash Flows Related to Natural Gas Futures Contracts

        Our earnings and cash flows historically have fluctuated significantly from period to period based on our futures activities, as all but a few of our futures contracts have not historically qualified for hedge accounting under the relative derivative accounting guidance We have therefore recorded any

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changes in the fair market value of these contracts that did not qualify for hedge accounting directly in our statements of operations in the line item derivative (gains) losses along with any realized gains or losses generated during the period. For example, we experienced derivative gains of $5.7 million for the three months ended June 30, 2008, and derivative losses of $0.3 million, $65.0 million, $13.7 million, $6.0 million and $0.3 million for the three months ended March 31, 2006, September 30, 2006, December 31, 2006, September 30, 2008 and December 31, 2008, respectively. We had no derivative gains or losses for the three months ended June 30, 2006, March 31, 2007, June 30, 2007, September 30, 2007, December 31, 2007, March 31, 2008, March 31, 2009, June 30, 2009 and September 30, 2009 related to our futures contracts. In accordance with our natural gas hedging policy, we plan to structure all subsequent futures contracts as cash flow hedges under the applicable derivative accounting guidance, but we cannot be certain that they will qualify. See "Risk Management Activities" below. If the futures contracts do not qualify for hedge accounting, we could incur significant increases or decreases in our earnings based on fluctuations in the market value of the contracts from period to period.

        Additionally, we are required to maintain a margin account to cover losses related to our natural gas futures contracts. Futures contracts are valued daily, and if our contracts are in loss positions at the end of a trading day, our broker will transfer the amount of the losses from our margin account to a clearinghouse. If at any time the funds in our margin account drop below a specified maintenance level, our broker will issue a margin call that requires us to restore the balance. Consequently, these payments could significantly impact our cash balances. At September 30, 2009, we had $3.9 million on deposit in margin accounts.

        The decrease in the value of our futures positions and any required margin deposits on our futures contracts that are in a loss position could significantly impact our financial condition in the future.

Volatility of Earnings Related to Series I Warrants

        Beginning January 1, 2009, under new accounting guidance, we are required to record the change in the fair market value of our Series I warrants in our financial statements. We recognized an expense of $0.2 million, $2.2 million and $15.4 million related to recording the fair market value changes of our Series I warrants in the quarters ended March 31, 2009, June 30, 2009 and September 30, 2009, respectively (see note 20 to our condensed consolidated financial statements contained elsewhere herein). Our earnings or loss per share may be materially impacted by future gains or losses we are required to take as a result of valuing our Series I warrants.

Debt Compliance

        Our credit agreement with PlainsCapital Bank ("PCB") ("Credit Agreement") requires us to comply with certain covenants. We may not incur indebtedness or liens except as permitted by the Credit Agreement, or declare or pay dividends. We must maintain, on a quarterly basis, minimum liquidity of not less than $6.0 million, accounts receivable balances, as defined, of not less than $8.0 million, consolidated net worth, as defined, of not less than $150.0 million, and a debt to equity ratio, as defined, of not more than 0.3 to 1. Beginning in the quarter ended June 30, 2009, we must also maintain a debt service ratio, as defined, of not less than 1.5 to 1 at each quarter end. Effective in the fourth quarter of 2008, we established a lock-box arrangement with PCB subject to the Credit Agreement. Funds received from our customers are remitted to the lock-box and then deposited to a PCB bank account. The remitted funds are not used to pay-down the balance of the credit agreement. However, if we default on the Credit Agreement, all of the obligations under the Credit Agreement will become due and payable and all funds received in our lock-box held by PCB will be applied to the balance due on the Credit Agreement. One of the events of default is the occurrence of a "material adverse change," which is a subjective acceleration clause. Based on the relevant accounting guidance, we have classified our debt pursuant to the Credit Agreement as short-term or long-term, as

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appropriate, and we believe an event of default is more than remote but not more likely than not. If we default on the Credit Agreement, all of the obligations under the Credit Agreement will become immediately due and payable and all funds received in our lockbox held by PCB and $2.5 million we have deposited with PCB in a payment reserve account will be applied to the balance due on the Credit Agreement. We were in compliance with the covenants as of September 30, 2009.

        One of our bank covenants is a requirement to maintain accounts receivable balances from certain subsidiaries above $8.0 million at each quarter-end during the term. To the extent natural gas prices continue to fall, which a significant portion of our revenues are derived from, or our volumes decline, we could violate this covenant in the future. Beginning with the quarter ended June 30, 2009, we are required to maintain a debt service ratio, as defined, of not less than 1.5 to 1. To the extent our operating results do not materialize as planned, we could violate this covenant in the future. In the event we violate either of these covenants, we would seek a waiver from the bank. We were in compliance with all of our covenants at September 30, 2009.

Risk Management Activities

        Our risk management activities, including the revised natural gas hedging policy adopted by our board of directors in February 2007 and revised by our board of directors on May 29, 2008, are discussed in Part II, Item 7 (Management's Discussion and Analysis of Financial Condition and Results of Operation) of our 2008 Annual Report on Form 10-K.

        In an effort to mitigate the volatility of our earnings related to our futures contracts and to reduce our risk related to fixed-price sales contracts, our board of directors revisited our risk management policies and procedures and adopted a revised natural gas hedging policy in February 2007, which was amended effective May 29, 2008 and restricts our ability to purchase natural gas futures contracts and offer fixed-price sales contracts to our customers. Unless otherwise agreed in advance by the board of directors and the derivative committee, we will conduct our futures activities and enter into fixed-price sales contracts only in accordance with the natural gas hedging policy, a complete copy of which was filed as Exhibit 99.1 to our Form 8-K filed with the SEC on June 20, 2008. Pursuant to the policy, we only 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 hedge effectively our exposure to cash flow variability related to such fixed-price sales contracts entered into after the date of the policy. The summary of the policy described above does not purport to be complete and is qualified in its entirety by reference to the copy of the policy previously filed.

        Due to the restrictions of our revised hedging policy, we expect to offer significantly fewer 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 increased costs as well as a return on our estimated cash requirements over the duration of the underlying futures contract. The amount of this price component will vary based on the anticipated volume to be covered under the fixed-price sales contract.

Critical Accounting Policies

        For the first nine months of 2009, there were no material changes to the "Critical Accounting Policies" discussed in Part II, Item 7 (Management's Discussion and Analysis of Financial Condition and Results of Operations) of our 2008 Annual Report.

Recently Issued Accounting Pronouncements

        For a description of recently issued accounting pronouncements, see note 20 to our condensed consolidated financial statements contained elsewhere herein.

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Results of Operations

        The following is a more detailed discussion of our financial condition and results of operations for the periods presented: