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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 March 31, 2013

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. Yes x No o

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 x 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 x

As of May 1, 2013, there were 88,514,691 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, 2012 and March 31, 2013

(Unaudited)

(In thousands, except share data)

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 Ended March 31, 2012 and 2013

(Unaudited)

(In thousands, except share and per share data)

See accompanying notes to condensed consolidated financial statements.

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Clean Energy Fuels Corp. and Subsidiaries

Condensed Consolidated Statements of Comprehensive Income (Loss)

For the Three Months Ended March 31, 2012 and 2013

(Unaudited)

(In thousands)

See accompanying notes to condensed consolidated financial statements.

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Clean Energy Fuels Corp.

Condensed Consolidated Statements of Cash Flows

For the Three Months Ended March 31, 2012 and 2013

(Unaudited)

(In thousands)

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)

(In thousands, except share and per share data)

Note 1—General

Nature of Business:  Clean Energy Fuels Corp., together with its majority and wholly owned subsidiaries (hereinafter collectively referred to as 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 trucking, airports, taxis, refuse, and public transit. The Company builds, operates, maintains or supplies approximately 358 natural gas fueling locations in thirty-two states within the United States, and in British Columbia and Ontario within Canada. The Company also generates revenue through operation and maintenance (“O&M”) agreements with certain customers, through building and selling or leasing natural gas fueling stations to its customers, through manufacturing and servicing natural gas fueling compressors and related equipment, providing natural gas vehicle conversions, providing design and engineering services for natural gas engine systems, processing and selling renewable natural gas (“RNG”), and through financing its customers’ vehicle purchases and selling tradable credits the Company generates by selling natural gas and RNG as a vehicle fuel, including credits (“LCFS Credits”) under the California low carbon fuel standard and Renewable Identification Numbers (“RIN Credits”) under the federal Renewable Fuel Standard Phase 2.

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 months ended March 31, 2012 and 2013. All intercompany accounts and transactions have been eliminated in consolidation. The three month periods ended March 31, 2012 and 2013 are not necessarily indicative of the results to be expected for the year ending December 31, 2013 or for any other interim period or for any future year.

Certain information and disclosures normally included in the notes to the 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 (“US GAAP”) 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, 2012 that are included in the Company’s Annual Report on Form 10-K filed with the SEC on February 28, 2013.

Use of Estimates:  The preparation of condensed consolidated financial statements in conformity with US GAAP 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 condensed consolidated financial statements and revenues and expenses recorded during the reporting period. Actual results could differ from those estimates.

Note 2—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 3—Restricted Cash

The Company classifies restricted cash as a current asset if the cash is expected to be used in operations within a year or to acquire a current asset. Otherwise, the restricted cash is classified as long-term. Restricted cash consisted of the following as of December 31, 2012 and March 31, 2013:

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Note 4—Investments

Available-for-sale investments are carried at fair value, inclusive of unrealized gains and losses. Net unrealized gains and losses are included in other comprehensive income (loss), net of applicable income taxes. Gains or losses on sales of available-for-sale investments are recognized on the specific identification basis.

The Company reviews available-for-sale investments for other-than-temporary declines in fair value below their cost basis each quarter, and whenever events or changes in circumstances indicate that the cost basis of an asset may not be recoverable. This evaluation is based on a number of factors, including the length of time and the extent to which the fair value has been below its cost basis and adverse conditions related specifically to the security, including any changes to the credit rating of the security. As of March 31, 2013, the Company believes its cost bases for its available-for-sale investments are properly recorded.

Short-term investments as of December 31, 2012 are summarized as follows:

Short-term investments as of March 31, 2013 are summarized as follows:

Note 5—Derivative Transactions

The Company, in an effort to manage its natural gas commodity price risk exposures related to certain contracts, utilizes derivative financial instruments.  From time to time, the Company enters into natural gas future contracts that are over-the-counter swap transactions that convert its index-based gas supply arrangements to fixed price arrangements.  As of March 31, 2013, all of the Company’s future contracts are being accounted for as cash flow hedges and are being used to mitigate the Company’s exposure to changes in the price of natural gas and not for speculative purposes. 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 condensed consolidated statements of operations or in accumulated other comprehensive income in the condensed consolidated balance sheets in accordance with the Financial Accounting Standards Board’s (“FASB”) authoritative guidance. For the three month periods ended March 31, 2012 and 2013, the Company recorded unrealized gains of $715 and $106, respectively, in other comprehensive income (loss) related to its futures contracts. Of the Company’s net futures contracts liability of $2 at March 31, 2013, $36 was recorded as a liability in accrued liabilities and $34 was recorded as an asset in prepaid expenses and other current assets, which are included in the Company’s condensed consolidated balance sheet. Of the Company’s net futures contracts liability of $107 at December 31, 2012, $5 was recorded as an asset in prepaid expenses and other current assets and $112 was recorded as an accrued liability in the Company’s condensed consolidated balance sheet. The Company’s ineffectiveness related to its futures contracts during the three month periods ended March 31, 2012 and 2013 was insignificant. For the three months ended March 31, 2012 and 2013, the Company recognized a loss of approximately $1,107 and $22, respectively, in cost of sales in the accompanying condensed consolidated statement of operations related to its futures contracts that were settled during the respective periods. As of March 31, 2013, the remaining unrecognized loss of $2 is recorded as a component of accumulated other comprehensive income (loss).  The Company expects to reclassify such unrecognized loss from accumulated other comprehensive income (loss) as cost of sales through June 30, 2013.

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The following table presents the notional amount and weighted-average fixed price per gasoline gallon equivalent of the Company’s natural gas futures contracts as of March 31, 2013:

Note 6—Other Receivables

Other receivables at December 31, 2012 and March 31, 2013 consisted of the following:

Note 7—Inventories

Inventories are stated at the lower of cost or market value on a first-in, first-out basis. Management’s estimate of market value includes a provision for slow-moving or obsolete inventory based upon inventory on hand and forecasted demand.

Inventories consisted of the following as of December 31, 2012 and March 31, 2013:

Note 8—Land, Property and Equipment

Land, property and equipment at December 31, 2012 and March 31, 2013 are summarized as follows:

As of December 31, 2012 and March 31, 2013, $12,087 and $6,601 are included in accounts payable balances, respectively, which are related to purchases of property and equipment. These amounts are excluded from the condensed consolidated statements of cash flows as they are non-cash investing activities.

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Note 9—Investments in Other Entities

The Company has invested in Clean Energy del Peru (“Peru JV”), a joint venture in Lima, Peru that operates CNG stations. The Company accounted for its investment in Peru JV under the equity method of accounting as the Company had the ability to exercise significant influence over Peru JV’s operations. In March 2013, the Company completed the sale of its entire ownership interest in Peru JV for $6,119 after receiving a dividend distribution of $1,091, and recognized a gain of $4,705.

Note 10—Accrued Liabilities

Accrued liabilities at December 31, 2012 and March 31, 2013 consisted of the following:

Note 11—Warranty Liability

The Company records warranty liabilities at the time of sale for the estimated costs that may be incurred under its standard warranty. Changes in the warranty liability are presented in the following tables:

Note 12—Long-term Debt

Revenue Bonds

On March 25, 2011, the Company’s 70% owned subsidiary, Dallas Clean Energy McCommas Bluff, LLC, a Delaware limited liability company (“DCEMB”), arranged for a $40,200 tax-exempt bond issuance (the “Revenue Bonds”). The Revenue Bonds will be repaid from the revenue generated by DCEMB from the sale of RNG. The Revenue Bonds are secured by the revenue and assets of DCEMB and are non-recourse to DCEMB’s direct and indirect parent companies, including the Company. The bond repayments are amortized through December 2024 and the average coupon interest rate on the bonds is 6.60%. The bond issuance closed March 31, 2011.  The bond proceeds are being primarily used to finance further improvements and expansion of the landfill gas processing facility owned by DCEMB at the McCommas Bluff landfill outside of Dallas, Texas.

Pursuant to the Loan Agreement, dated as of January 1, 2011 (the “Loan Agreement”), between DCEMB and the Mission Economic Development Corporation (the “Issuer”), DCEMB has covenanted with the Issuer to make loan repayments equal to the principal and interest coming due on the Revenue Bonds. DCEMB executed a promissory note, dated March 31, 2011 (the “Note”), as evidence of its obligations under the Loan Agreement. Pursuant to the Trust Indenture, dated as of January 1, 2011 (the “Indenture”), the Issuer has pledged and assigned to the Trustee all of the Issuer’s right, title and interest in and to the Loan Agreement (with certain specified exceptions) and the Note.

The obligations of DCEMB under the Loan Agreement are secured by a Leasehold Deed of Trust, Assignment of Rents, Security Agreement and Fixture Filing, dated as of January 1, 2011 (the “Deed of Trust”), executed by DCEMB in favor of the deed of trust trustee named therein for the benefit of the Bank of New York Mellon Trust Company, N.A., as Trustee (the “Trustee”). In addition, DCEMB executed a Security Agreement (the “Security Agreement”), as security for its obligations, pursuant to which DCEMB granted to the Trustee a security interest in all right, title and interest of DCEMB to the Collateral (as defined in the Security Agreement), which includes, but is not limited to, DCEMB’s rights, title and interest in any gas sale agreements, including the gas sale agreement with Shell Energy North America (US), L.P. (“Shell Energy,” and such gas sale agreement, the “Shell Gas Sale Agreement”), and the funds and accounts held under the Indenture.

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Pursuant to a Consent and Agreement, by and between Shell Energy, The Bank of New York Mellon Trust Company, N.A., as Depository Bank (the “Depository Bank”), DCEMB and the Trustee, dated as of January 1, 2011 (the “Consent Agreement”), Shell Energy agreed to make all payments due to DCEMB under the Shell Gas Sale Agreement to the Depository Bank. In addition, other revenues generated through the sale of gas produced at the facility will be paid directly to the Depository Bank pursuant to a Depository and Control Agreement, dated as of January 1, 2011 (the “Depository Agreement”), among DCEMB, the Trustee and the Depository Bank.

All payments received by the Depository Bank are placed into various accounts in accordance with the requirements of the Indenture and the Depository Agreement. The funds in these accounts is used to service required debt payments, finance further improvements and expansion of the landfill gas processing facility owned by DCEMB, finance the operations and maintenance of DCEMB, finance certain expenses associated with setting up and maintaining the accounts, and other uses as prescribed in the Depository Agreement. The Depository Bank makes payments out of these accounts in accordance with the requirements of the Depository Agreement. At the end of each month after all required account fundings have been fulfilled in accordance with the Depository Agreement, all remaining excess funds are placed into a Surplus Account (as defined). The funds in the Surplus Account are delivered to DCEMB so long as (i) DCEMB’s Debt Service Coverage Ratio (as defined) for the most recent four calendar quarters then ended equals or exceeds 1.25:1, (ii) DCEMB’s Debt Service Coverage Ratio (as defined) is reasonably projected to equal or exceed 1.25:1 for the next four calendar quarters, (iii) no events of default have occurred as defined by the Indenture and the Loan Agreement, and (iv) after giving effect to the transfer, DCEMB’s Minimum Days Cash on Hand (as defined) shall be, or shall at any time be projected to be, more than the lesser of thirty-five Days Cash on Hand (as defined) or $1,300. Due to these restrictions on this cash, the Company has classified all of this cash as restricted cash on the balance sheet. The Company records the restricted cash that is expected to be received and used within the next 12 months from the Depository Bank for working capital and operating purposes as current in its balance sheet, and presents the remaining balance as non-current in the line item notes receivable and other long term assets. At March 31, 2013, $952 was recorded as long term restricted cash and $8,838 was recorded as short term restricted cash in the accompanying condensed consolidated balance sheet.

Pursuant to a Collateral Assignment and Consent Agreement with Atmos Pipeline—Texas (“Atmos”), DCEMB has collaterally assigned to the Trustee, subject to certain reserved rights and the consent of Atmos, the transportation agreements of the Company with Atmos.

The Indenture and the Loan Agreement have certain non-financial debt covenants with which DCEMB must comply. As of March 31, 2013, DCEMB was in compliance with all its debt covenants.

Purchase Notes

In connection with the closing of the Company’s acquisition of IMW, the Company agreed to make future payments consisting of four annual payments in the amount of $12,500 which were subsequently amended to be CAD$5,000 and $7,500. Each payment under the IMW Notes will consist of CAD$5,000 in cash and $7,500 in cash and/or shares of the Company’s common stock (the exact combination of cash and/or stock to be determined at the Company’s option). In addition, pursuant to a security agreement executed at closing, the IMW Notes are secured by a subordinate security interest in IMW. In January 2011, the Company paid $5,000 in cash and $7,500 in shares of its common stock. The Company paid CAD$5,000 in cash in January 2012 and $3,750 in shares of its common stock in each of August 2012 and October 2012. The Company paid CAD$5,000 in cash and $7,500 in shares of its common stock in February 2013. The IMW Notes that were settled with shares of the Company’s common stock are not included in the condensed consolidated statements of cash flows as they are non-cash financing activities.

In connection with the closing of the Company’s acquisition of Northstar, the Company agreed to make future payments consisting of five annual payments in the amount of $700 each with the first payment due December 15, 2011. Each of the first two payments of $700 was paid in December 2011 and 2012, respectively.

In connection with the closing of the Company’s acquisition of the natural gas fuel infrastructure construction business of Weaver Electric, Inc. on October 3, 2011, the Company paid $1,000 in cash and agreed to make four additional annual payments in the amount of $250 each with the first payment due October 3, 2012 (the “Weaver Notes”). In May 2012, the Company prepaid $125 of the October 2012 payment, and the remaining amount of such payment was paid in October 2012.

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In connection with the closing of the Company’s acquisition of ServoTech on April 30, 2012, the Company paid $1,400 in cash at closing and paid an additional $1,400 in cash on October 31, 2012.

The difference between the carrying amount and the face amount of these obligations is being accreted to interest expense over the remaining term of the obligations.

HSBC Lines of Credit

In connection with the closing of the Company’s acquisition of IMW, the Company entered into an Assumption Agreement (the “Assumption Agreement”) with HSBC Bank Canada (“HSBC”) pursuant to which the Company assumed the obligations and liabilities of IMW under the following arrangements with HSBC (collectively, the “IMW Lines of Credit”):

(i)                                     An operating line of credit with a limit of $13,000 in Canadian dollars (“CAD”) to assist in financing the day-to-day working capital needs of IMW. The interest on amounts outstanding shall be payable at IMW’s option at (a) HSBC’s Prime Rate plus 1.00% per annum, (b) HSBC’s U.S. Base Rate plus 1.00% per annum, or LIBOR plus 2.25% per annum, subject to availability.

(ii)                                  A demand revolving line of credit with a limit of CAD$2,000 bearing interest at the same rate as that of the operating line of credit discussed above, to assist in financing IMW’s import requirements.

(iii)                               A demand revolving bank guarantee and standby letter of credit line with a limit of CAD$1,115.

(iv)                              A bank guarantee line with a limit of CAD$3,000, which allows IMW to provide guarantees and/or standby letters of credit to overseas suppliers or bid/performance deposits on contracts.

(v)                                 A forward exchange contract line with a limit of CAD$13,750 that allows IMW to enter into foreign exchange forward contracts up to the notional limit of CAD$13,750 (no forward exchange contracts were outstanding at March 31, 2013).

(vii)                           An operating line of credit with a limit of 5,000 Renminbi (“RMB”) (CAD$810) bearing interest at the 6 month People’s Bank of China rate plus 2.5% and a sub-limit bank guarantee line of 5,000 RMB. The aggregate of the balances in the lines cannot exceed 5,000 RMB.

(viii)                        A 16,750 Bangladeshi Taka (CAD$215) operating line of credit bearing interest at 14%.

(ix)                              A 170,000 Colombian Peso (CAD$95) operating line of credit bearing interest at the Colombia benchmark rate plus 7 to 12%.

The IMW Lines of Credit are secured by a general security agreement providing a first priority security interest in all present and after acquired personal property of IMW (the “Security”). The IMW Lines of Credit contain no fixed repayment terms or mandatory principal payments and are due on demand. Based on the relevant accounting guidance, the Company has classified this debt pursuant to the credit agreement as short-term given that it is due on demand.

The Assumption Agreement with HSBC sets forth certain financial covenants with which IMW must comply, including: 1) its ratio of debt to tangible net worth must be no greater than 3.0 to 1.0, 2) it must maintain a tangible net worth of at least CAD$7,000 and 3) its ratio of current assets to current liabilities may not be less than 1.25 to 1.0. IMW was in compliance with the financial covenants as of March 31, 2013.

In addition, the Company and IMW agreed that should the making of any scheduled payment by IMW to the seller of IMW under the IMW Notes result in IMW being in breach of the Assumption Agreement, the IMW Lines of Credit or the Security, the Company shall furnish IMW with the funds needed to remain in compliance with the Assumption Agreement, the IMW Lines of Credit and the Security. Further, the Company and IMW agreed that should IMW make any future earn-out payments to the seller of IMW in connection with the acquisition of IMW, and should the making of such earn-out payments result in IMW being in breach of the Assumption Agreement, the IMW Lines of Credit or the Security, then the Company shall furnish IMW with the funds needed to make such earn-out payments and remain in compliance with the Assumption Agreement, the IMW Lines of Credit and the Security.

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Chesapeake Notes

On July 11, 2011, the Company entered into a Loan Agreement (the “CHK Agreement”) with Chesapeake NG Ventures Corporation (“Chesapeake”), an indirect wholly owned subsidiary of Chesapeake Energy Corporation, whereby Chesapeake agreed to purchase from the Company up to $150,000 of debt securities for the development, construction and operation of liquefied natural gas stations (the “CHK Financing”) pursuant to the issuance of three convertible promissory notes, each having a principal amount of $50,000 (each a “CHK Note” and collectively the “CHK Notes”). Chesapeake Energy Corporation guaranteed Chesapeake’s commitment to purchase the CHK Notes under the CHK Agreement.

The first CHK Note was issued on July 11, 2011, the second CHK Note was issued on July 10, 2012 and the Company expects to issue the third CHK Note on or about June 28, 2013. The CHK Notes bear interest at the rate of 7.5% per annum (payable quarterly, in arrears, on March 31, June 30, September 30 and December 31 of each year) and are convertible at Chesapeake’s option into shares of the Company’s common stock at a conversion price of $15.80 per share (the “CHK Conversion Price”). Subject to certain restrictions, the Company can force conversion of each CHK Note into shares of the Company’s common stock if, following the second anniversary of the issuance of a CHK Note, the Company’s shares of common stock trade at a 40% premium to the CHK Conversion Price for at least 20 trading days in any consecutive 30 trading day period. The entire principal balance of each CHK Note is due and payable seven years following its issuance, and the Company may repay each CHK Note in shares of the Company’s common stock or cash. The CHK Agreement restricts the use of the CHK financing proceeds to financing the development, construction and operation of liquefied natural gas stations and payment of certain related expenses. At March 31, 2013, approximately $483 of these funds were included in long term restricted cash as the Company anticipates primarily using the funds to build LNG fueling stations. The CHK Agreement also provides for customary events of default which, if any of them occurs, would permit or require the principal of, and accrued interest on, the CHK Notes to become, or to be declared, due and payable.

In connection with the CHK Financing, the Company also entered into a Registration Rights Agreement, dated July 11, 2011, with Chesapeake (the “CHK Registration Rights Agreement”) pursuant to which the Company agreed, subject to the terms and conditions of the CHK Registration Rights Agreement, to (i) file with the Securities and Exchange Commission one or more registration statements relating to the resale of the Company’s common stock issuable upon conversion of the CHK Notes, and (ii) at the request of Chesapeake, to participate in one or more underwritten offerings of the Company’s common stock issuable upon conversion of the CHK Notes. If the Company does not meet certain of its obligations under the CHK Registration Rights Agreement with respect to the registration of the Company’s common stock, it will be required to pay monthly liquidated damages of 0.75% of the principal amount of the CHK Note represented by the Company’s common stock included (or to be included, as the case may be) in the applicable registration statement until the related obligation is met. As of March 31, 2013, the Company met its obligations under the CHK Registration Rights Agreement.

SLG Notes

On August 24, 2011, the Company entered into Convertible Note Purchase Agreements (each, an “SLG Agreement” and collectively the “SLG Agreements”) with each of Springleaf Investments Pte. Ltd., a wholly-owned subsidiary of Temasek Holdings Pte. Ltd., Lionfish Investments Pte. Ltd., an investment vehicle managed by Seatown Holdings International Pte. Ltd., and Greenwich Asset Holding Ltd., a wholly-owned subsidiary of RRJ Capital Master Fund I, L.P. (each, a “Purchaser” and collectively, the “Purchasers”), whereby the Purchasers agreed to purchase from the Company $150,000 of 7.5% convertible notes due in August 2016 (each a “SLG Note” and collectively the “SLG Notes”). The transaction closed and the SLG Notes were issued on August 30, 2011. On March 1, 2012, Springleaf Investments Pte. LTD transferred $24,000 principal amount of the SLG Notes to Baytree Investments (Mauritius) Pte Ltd.

The SLG Notes bear interest at the rate of 7.5% per annum (payable quarterly, in arrears, on March 31, June 30, September 30 and December 31 of each year) and are convertible at each Purchaser’s option into shares of the Company’s common stock at a conversion price of $15.00 per share (the “SLG Conversion Price”). Subject to certain restrictions, the Company can force conversion of each SLG Note into shares of the Company’s common stock if, following the second anniversary of the issuance of the SLG Notes, the Company’s shares of common stock trade at a 40% premium to the SLG Conversion Price for at least 20 trading days in any consecutive 30 trading day period. The entire principal balance of each SLG Note is due and payable five years following its issuance, and the Company may repay the principal balance of each SLG Note in shares of the Company’s common stock or cash. The SLG Agreements also provide for customary events of default which, if any of them occurs, would permit or require the principal of, and accrued interest on, the SLG Notes to become, or to be declared, due and payable. In April 2012, $1,003 of principal and accrued interest under an SLG Note was converted by the holder thereof into 66,888 shares of the Company’s common stock. In January and February 2013, $4,030 of principal and accrued interest under an SLG Note was converted by the holder thereof into 268,664 shares of the Company’s common stock. Such conversions were not included in the condensed consolidated statements of cash flows as it is a non-cash financing activity.

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In connection with the SLG Agreements, the Company also entered into a Registration Rights Agreement, dated August 30, 2011, with each of the Purchasers (the “SLG Registration Rights Agreements”) pursuant to which the Company agreed, subject to the terms and conditions of the SLG Registration Rights Agreements, to (i) file with the Securities and Exchange Commission one or more registration statements relating to the resale of the Company’s common stock issuable upon conversion of the SLG Notes, and (ii) at the request of the Purchasers, participate in one or more underwritten offerings of the Company’s common stock issuable upon conversion of the SLG Notes. If the Company does not meet certain of its obligations under the SLG Registration Rights Agreements with respect to the registration of the Company’s common stock, it will be required to pay monthly liquidated damages of 0.75% of the principal amount of the SLG Note represented by the Company’s common stock included (or to be included, as the case may be) in the applicable registration statement until the related obligation is met, not to exceed 4% of the aggregate principal amount of the SLG Notes per annum. As of March 31, 2013, the Company met its obligations under the SLG Registration Rights Agreement.

GE Loans

On November 7, 2012, the Company, through two wholly owned subsidiaries (the “Borrowers”), entered into a financing arrangement with General Electric Capital Corporation (“GE,” and the agreement governing such arrangement, the “GE Credit Agreement”). Pursuant to the GE Credit Agreement, GE Capital agreed to loan to the Borrowers up to an aggregate of $200,000 to finance the development, construction and operation of two LNG production facilities (individually a “Project” and together the “Projects”), each with an expected production capacity of approximately 250,000 LNG gallons per day. The Company expects to sell the LNG produced by the Projects through America’s Natural Gas Highway, a nationwide network of natural gas truck fueling stations, which the Company is building along major transportation corridors in the United States.

The Borrowers’ ability to obtain loans under the GE Credit Agreement (collectively, “Loans” and, with respect to each Project “Tranche A Loans” and “Tranche B Loans”) for the Projects is subject to the satisfaction of certain conditions, including each of the (i) acquisition of title to, or leasehold interests in, the sites upon which the Projects will be constructed, (ii) receipt of all governmental approvals necessary in connection with the design, development, ownership, construction, installation, operation and maintenance of the Projects, (iii) commitment of all utility services necessary for the construction and operation of the Projects, and (iv) execution of an engineering, procurement and construction contract for each Project by the Company and GE Oil & Gas, Inc.

The GE Credit Agreement further provides that (i) if initial Loans are not made prior to December 31, 2014, the GE Credit Agreement will automatically terminate, (ii) each Project must be completed by the earlier of (a) the date thirty months after the funding of the initial Loans with respect to such Project and (b) December 31, 2016 (with respect to each Project, the “Date Certain”), (iii) the then existing Loans with respect to each Project must be converted into term loans with eight year amortization schedules (“Term Loans”) on or before the Date Certain with respect to such Project (the date of such conversion with respect to each Project, the “Conversion Date”), provided that if such Loans are not converted into Term Loans by the applicable Date Certain, such Loans must be repaid by the applicable Date Certain, (iv) each Term Loan will be due and payable on the eighth anniversary of the Conversion Date with respect to such Term Loan, and (v) at any time prior to the applicable Conversion Date, the Loans may be prepaid in whole, and at any time after the applicable Conversion Date, the Loans may be prepaid in whole or in part. The Company expects the Loans to bear interest at an annual rate equal to the then- current LIBOR rate plus 7.00%, provided that for purposes of the GE Credit Agreement, the then-current LIBOR rate will always be at least 1.00%. The GE Credit Agreement includes various customary covenants, including debt service coverage ratios, and also provides for customary events of default which, if such events occur, would permit or require the Loans to become or to be declared due and payable. As of March 31, 2013, the Company has not drawn any money under the GE Credit Agreement and was in compliance with the financial covenants.

The Loans are secured by (i) a first priority security interest in all of the Borrowers’ assets, including the Projects, and (ii) a pledge of the Borrowers’ outstanding ownership interests. In addition, the Company has executed a guaranty in favor of GE (“Guaranty”), pursuant to which the Company has guaranteed all of the Borrowers’ obligations under the GE Credit Agreement, including repayment of all Loans.

The Company and GE also entered an equity contribution agreement (the “EC Agreement”) pursuant to which the Company agreed to pay at least 25% of the budgeted cost of the Projects and all additional costs that exceed such expected budgeted costs, in each case, in the form of equity contributions to the Borrowers (“Equity Contributions”). The EC Agreement also requires Clean Energy to provide, concurrent with GE’s extension of the initial Loans under the GE Credit Agreement, letter(s) of credit in an amount equal to the Company’s then-current unfunded Equity Contributions.

Concurrently with the execution of the GE Credit Agreement, the Company issued to GE a warrant (“GE Warrant”) to purchase up to 5,000,000 shares of the Company’s common stock (see note 13).

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Long-term debt at December 31, 2012 and March 31, 2013 consisted of the following:

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. In the three months ended March 31, 2013, 5,000,000 shares of common stock related to the GE Warrant were included in the basic and dilutive net loss per share calculation.  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 for the three months ended March 31, 2012 and 2013, respectively, as the inclusion of the securities would be anti-dilutive to the calculation. The amounts outstanding as of March 31, 2012 and 2013 for these instruments are as follows:

Note 14—Stock-Based Compensation

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

Stock Options

The following table summarizes the Company’s stock option activity during the three months ended March 31, 2013:

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As of March 31, 2013, there was $21,539 of total unrecognized compensation cost related to non-vested shares. That cost is expected to be recognized over a weighted average period of 1.4 years. The total fair value of shares vested during the three months ended March 31, 2013 was $7,609.

The Company plans to issue new shares to its employees upon the employees’ exercise of their options. The intrinsic value of all options exercised during the three months ended March 31, 2012 and 2013 was $12,955 and $252, respectively.

The Company recorded $3,342 and $4,007 of stock option expense during the three months ended March 31, 2012 and 2013, respectively. The Company has not recorded any tax benefit related to its stock option expense.

Restricted Stock Units

The Company issued 1,545,000 restricted stock units (“RSUs”) to certain key employees during 2012.  A holder of RSUs will receive one share of the Company’s common stock for each RSU he holds if (x) between two years and four years from the date of grant of the RSU, the closing price of the Company’s common stock equals or exceeds, for twenty consecutive trading days, 135% of the closing price of the Company’s common stock on the RSU grant date (the “Stock Price Condition”) and (y) the holder is employed by the Company at the time the Stock Price Condition is satisfied. If the Stock Price Condition is not satisfied prior to four years from the date of grant, the RSUs will be automatically forfeited. The RSUs are subject to the terms and conditions of the Company’s Amended and Restated 2006 Equity Incentive Plan and a Notice of Grant of Restricted Stock Unit and Restricted Stock Unit Agreement.

As of March 31, 2013, there was $7,548 of total unrecognized compensation cost related to non-vested units. That cost is expected to be recognized over a weighted average period of 0.9 years.  The Company recorded $1,338 and $2,205 of expense during the three months ended March 31, 2012 and 2013, respectively, related to the RSUs. The Company has not recorded any tax benefit related to its RSU expense.

Note 15—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 condensed 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 may become party to various legal actions that arise in the ordinary course of its business. During the course of its operations, the Company is also 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 condensed 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 condensed consolidated financial position, results of operations, or liquidity.

Note 16—Income Taxes

The Company’s income tax provision for the three months ended March 31, 2013 was $1,805, which includes a discrete tax expense of $1,409 related to the sale of the Company’s interest in Peru JV during the period.  The effective tax rate for the three month periods ended March 31, 2012 and 2013 are different from the federal statutory tax rate primarily as a result of losses for which no tax benefit has been recognized.

The Company did not record a change in its liability for unrecognized tax benefits or penalties in the three months ended March 31, 2012 or March 31, 2013, and the net interest incurred was immaterial for such periods.

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Note 17—Fair Value Measurements

The Company 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 nonrecurring basis. Under the standard, 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 standard 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 developed based on market data obtained from sources independent of the Company. Unobservable inputs are inputs that reflect the Company’s assumptions about the factors market participants would use in valuing the asset or liability 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.

During the three months ended March 31, 2013, the Company’s financial instruments consisted of available-for-sale securities, natural gas futures contracts, debt instruments, a contingent consideration obligation, and its Series I warrants. For securities available-for-sale, the fair value is determined by the most recent trading prices available for each security or for comparable securities, and thus represent Level 2 fair value measurements. The Company uses quoted forward price curves, discounted to reflect the time value of money, to value its natural gas futures contracts which is considered to be a Level 2 fair value measurement. The Company uses projected financial results for the respective entities, discounted to reflect the time value of money, to value its contingent consideration obligations which are considered to be Level 3 fair value measurements. The fair market value of the Company’s debt instruments approximated their carrying values at March 31, 2013. The Company uses the Black-Scholes model to value the Series I warrants. The Company believes the best method to approximate the market participant’s view of the volatility of its Series I warrants has been to use the implied volatilities of its short-term (i.e. 3 to 9 month) traded options and extrapolate the data over the remaining term of the Series I warrants, which was approximately 3.08 years as of March 31, 2013. This method has been utilized consistently in the periods presented. Given that the extrapolation beyond the term of the short term exchange traded options is not based on observable market inputs for a significant portion of the remaining term of the warrants, the Series I warrants have been classified as a Level 3 fair value measurement in the table below.

The following tables provide information by level for assets and liabilities that are measured at fair value on a recurring basis as of December 31, 2012 and March 31, 2013, respectively:

(1) Included in short-term investments in the condensed consolidated balance sheets. See note 4 for further information.

(2) See note 5 for further information.

(3) The current portion is included in accrued liabilities, and the long-term portion is included in other long-term liabilities in the condensed consolidated balance sheets.

(4) Included in other long-term liabilities in the condensed consolidated balance sheets.

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The following tables provide a reconciliation of the beginning and ending balances of items measured at fair value on a recurring basis in the table above that used significant unobservable inputs (Level 3).

Valuation processes for Level 3 fair value measurements and sensitivity to changes in significant unobservable inputs

Fair value measurements of liabilities which fall within Level 3 of the fair value hierarchy are determined by the Company’s accounting department, who report to the Company’s Chief Financial Officer. The fair value measurements are compared to those of the prior reporting periods to ensure that changes are consistent with expectations of management based upon the sensitivity and nature of the inputs.

Contingent Consideration

Pursuant to the terms presented in the Asset Purchase Agreement, the IMW shareholder will earn additional consideration if IMW achieves certain minimum gross profit targets in fiscal years 2011 through 2014. Therefore, the Company estimated the fair value of the contingent consideration based on the payout structure using the following inputs as of March 31, 2013:

Generally, a positive change in the assumptions used for the probability of achieving a higher gross profit target threshold would result in a directionally similar change in the estimated fair value of the contingent consideration, and thus an increase in the associated liability.

Series I Warrant Liability

The Company estimated the fair value of its Series I warrant liability using the Black-Scholes Model based on the following inputs as of March 31, 2013:

Significant changes in any of those inputs in isolation can result in a significant change in the fair value measurement. Generally, a positive change in the market price of the Company’s common stock, an increase in the volatility of the Company’s

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common stock, or an increase in the remaining term of the warrant would result in a directionally similar change in the estimated fair value of the Company’s Series I warrants and thus an increase in the associated liability. An increase in the assumed discount rate or a decrease in the positive differential between the warrant’s exercise price and the market price of the Company’s common stock would result in a decrease in the estimated fair value measurement of the Series I warrants and thus a decrease in the associated liability. The Company has not, nor plans to, declare dividends on its common stock, and thus, there is no directionally similar change in the estimated fair value of the warrants due to the dividend assumption.

Non-financial assets

No impairments of long-lived assets measured at fair value on a non-recurring basis have been incurred during the three months ended March 31, 2012 and 2013.  The Company’s use of these nonfinancial assets does not differ from their highest and best use as determined from the perspective of a market participant.

Note 18—Recently Adopted Accounting Changes and Recently Issued Accounting Standards

On January 1, 2013, the Company adopted Accounting Standards Update (“ASU”) No. 2013-02, Reporting of Amounts Reclassified Out of Accumulated Other Comprehensive Income (ASU 2013-02). The ASU requires an entity to report the effect of significant reclassifications out of accumulated other comprehensive income on the respective line items into net income if the amount being reclassified is required under US GAAP to be reclassified in its entirety to net income. An entity shall provide this information together, in one location, in either of the following ways: a) on the face of the statement where net income is presented, or b) as a separate disclosure in the notes to the financial statements. The gain or loss resulting from the settlement of the Company’s futures contracts is the only significant item being reclassified during the three-month periods ended March 31, 2012 and 2013.  The Company has disclosed this information in note 5.

Note 19—Volumetric Excise Tax Credit (VETC)

On January 2, 2013, the American Taxpayer Relief Act was signed into law which extended VETC through December 31, 2013 and made it retroactive to January 1, 2012. 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 recognized during the three month period ended March 31, 2013 was $26,217, which includes $20,800 for the 2012 VETC credits.

Note 20 — Subsequent Events

On April 25, 2013 (“Closing Date”), Mavrix, LLC (“Issuer”), a newly-formed special purpose vehicle subsidiary of Clean Energy Renewable Fuels, LLC (“CERF”), entered a Note Purchase Agreement (“NPA”) with Massachusetts Mutual Life Insurance Company (“Note Purchaser”).  CERF and Issuer are subsidiaries of the Company.  Issuer owns all of the equity interests in Canton Renewables, LLC (“Canton”) and 70% of the equity interests in Dallas Clean Energy, LLC, which owns all of the equity interests in Dallas Clean Energy McCommas Bluff, LLC (“DCEMB,” and together with Canton, the “Project Companies”). Canton owns a RNG extraction and processing project at the Sauk Trail Hills Landfill in Canton, Michigan and DCEMB owns the RNG extraction and processing project at the McCommas Bluff Landfill in Dallas, Texas.

Pursuant to the NPA, on the Closing Date, Note Purchaser (i) purchased a secured multi-draw promissory note (“Mavrix Note”) from Issuer in the maximum aggregate principal amount of $30,000,000 (the “Maximum Principal Amount”), and (ii) funded an initial advance of $5,000,000 under the Mavrix Note.  Subject to the Issuer and the Project Companies satisfying certain conditions described in the NPA, Note Purchaser will make additional advances under the Mavrix Note, up to the Maximum Principal Amount.  Issuer will use the proceeds from the sale of the Mavrix Note and any advances thereunder to (x) pay any transaction costs and fees related to the NPA and the issuance of the Mavrix Note and (y) make distributions to its direct and indirect parent companies.  The Issuer’s direct and indirect parent companies plan to use such distributions to finance construction of additional RNG extraction and processing projects and for working capital purposes.

The Mavrix Note matures 12 years from the Closing Date and bears base interest at the rate of 12% per annum and paid in kind interest at the rate of 2.0% per annum.  The principal amount of the Mavrix Note will be repaid in 28 quarterly installments commencing on June 30, 2018, provided that the NPA requires mandatory prepayment of such principal amount upon certain casualty or condemnation events, assets sales or extraordinary transactions.  In addition, the Issuer may not voluntarily repay the Mavrix Note until the third anniversary of the Closing Date and, subject to the foregoing restriction, the Issuer must pay a prepayment premium if it prepays the Mavrix Note prior to the ninth anniversary of the Closing Date.

The Mavrix Note is secured by (i) a first priority security interest in all of Issuer’s assets and (ii) a pledge of Issuer’s outstanding equity interests.  In addition, the NPA includes various customary affirmative and negative covenants and also provides for customary events of default which, if such events occur, would permit or require the Mavrix Note to become, or to be declared, due and payable.  The Mavrix Note is non-recourse to the Company.

On May 6, 2013 (the “Acquisition Date”), Clean Energy (“Clean Energy”), a wholly owned subsidiary of the Company, entered into a Stock Purchase Agreement (the “Purchase Agreement”) with Mansfield Energy Corp. (“Mansfield”) and its wholly owned subsidiary Mansfield Gas Equipment Systems Corporation (“MGES”).  Under the terms of the Purchase Agreement, on the Acquisition Date, Clean Energy purchased from Mansfield all of the issued and outstanding capital stock of MGES for $20,000,000, paid 50% in cash and 50% in shares of the Company’s common stock (the “Shares”).  The Purchase Agreement also provides for Mansfield to receive additional consideration if Closing Working Capital (as defined in the Purchase Agreement) is greater than $3,000,000. MGES is primarily engaged in the business of providing CNG station design and construction and CNG equipment repair and maintenance services.

Mansfield further agreed that, for a period beginning on the Acquisition Date and ending on October 16, 2013 (the “Lock-Up Expiration Date”), it will not sell, transfer or make any other disposition of all or any portion of the Shares.  Clean Energy agreed to file with the Securities and Exchange Commission (“SEC”) a registration statement covering the resale of the Shares and to cause such registration statement to be declared effective by the SEC on or before the Lock-Up Expiration Date.  In addition, the Agreement provides that Mansfield will, subject to certain limitations, indemnify Clean Energy for damages and losses incurred or suffered by Clean Energy as a result of, among other things, breaches of Mansfield’s and MGES’ representations, warranties and covenants contained in the Purchase Agreement.

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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, 2012 contained in our 2012 Annual Report on Form 10-K filed with the SEC on February 28, 2013, as well as the consolidated financial statements and notes contained therein.  Unless the context indicates otherwise, all references to “Clean Energy,” the “Company,” “we,” “us,” or “our” in this MD&A and elsewhere in this report refer to Clean Energy Fuels Corp. together with its majority and wholly owned subsidiaries.

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 2012 Annual Report on Form 10-K (the”2012 10-K”). In preparing this MD&A, we presume that readers have access to and have read the MD&A in our 2012 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.

We are the leading provider of natural gas as an alternative fuel for vehicle fleets in the United States and Canada, based on the number of stations operated and the amount of gasoline gallon equivalents of compressed natural gas (“CNG”) and liquefied natural gas (“LNG”) delivered. We design, build, operate and maintain fueling stations and supply our customers with CNG fuel for light, medium and heavy-duty vehicles and LNG fuel for medium and heavy-duty vehicles. We also sell non-lubricated natural gas compressors and related equipment used in CNG stations and LNG stations, convert light and medium duty vehicles to run on natural gas, provide design and engineering services for natural gas engine systems, produce renewable natural gas (“RNG”), which can be used as vehicle fuel or sold for power generation, and sell tradable credits we generate by selling natural gas and RNG as a vehicle fuel, including credits we generate under the California Low Carbon Fuel Standard (“LCFS Credits”) and Renewable Idenfiication Numbers (“RIN Credits”) we generate under the federal Renewable Fuel Standard Phase 2. In addition, we help our customers acquire and finance natural gas vehicles and obtain local, state and federal grants and incentives.

Overview

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

Sources of revenue.  We generate revenues by selling CNG and LNG, providing operations and maintenance (“O&M”) services to our vehicle fleet customers, designing and constructing fueling stations and selling or leasing those stations to our customers, selling RNG, selling converted natural gas vehicles, providing design and engineering services for natural gas engine systems, selling non-lubricated natural gas fueling compressors and related equipment and maintenance services, providing financing for our customers’ natural gas vehicle purchases and selling tradable credits, including LCFS Credits and RIN Credits.

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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 O&M services, but do not sell the CNG or LNG, plus (iii) our proportionate share of the gasoline gallon equivalents sold as CNG by our joint venture in Peru (through March 2013 when we sold our interest in the joint venture in Peru), plus (iv) our proportionate share of the gasoline gallon equivalents of RNG produced and sold as pipeline quality natural gas by our RNG production facilities, (2) our gross margin (which we define as revenue minus cost of sales), and (3) net income (loss) attributable to us. The following table, which you should read in conjunction with our condensed consolidated financial statements and notes contained elsewhere in this quarterly report on Form 10-Q and our consolidated financial statements and notes contained in our 2012 Annual Report on Form 10-K, presents our key operating data for the years ended December 31, 2010, 2011, and 2012 and for the three months ended March 31, 2012 and 2013:

(1)         See discussion under “Operations — Government Incentives” below.

Key trends in 2010, 2011, 2012 and the first three months of 2013.  According to the EIA, demand for natural gas fuels in the United States increased by approximately 19% during the period January 1, 2010 through December 31, 2012. We believe this growth in demand was attributable primarily to the rising prices of gasoline and diesel relative to CNG and LNG during these periods and increasingly stringent environmental regulations affecting vehicle fleets.

The number of fueling stations we served grew from 196 at December 31, 2009 to 358 at March 31, 2013 (an 82.7% increase). Included in this number are all of the CNG and LNG fueling stations we own, maintain or with which we have a fueling supply contract. The amount of CNG, RNG, and LNG gasoline gallon equivalents we delivered from 2010 to 2012 increased by 58.8%. The increase in gasoline gallon equivalents delivered was the primary contributor to increased revenues during 2010, 2011 and 2012. In addition, beginning in 2011, we also benefitted from increased revenues from compressor sales and fueling station installations as a result of our acquisitions of IMW Industries, Ltd. (“IMW”) and Wyoming Northstar Incorporated and its affiliated companies (“Northstar”), which occurred during the third and fourth quarters of 2010.

Our fuel cost of sales also increased during these periods, which was attributable primarily to increased costs related to delivering more CNG and LNG to our customers in 2010 through 2012 and the first quarter of 2013. Starting in 2011, the cost of sales related to compressors sold through IMW and fueling station installations performed by Northstar also contributed to the increase.   Cost of sales can vary between periods due to timing of station construction sale activity.

Since the last half of 2009, we have experienced reduced margins in certain markets, particularly in the municipal transit and refuse sectors. The reduction in margins is primarily a result of increased competition and sales agreements with larger entities that have greater pricing leverage. Also, in many cases, our agreements with our customers, including governmental agencies, are subject to a competitive bidding process and we have been required to reduce our prices to maintain our contracts as they come up for bid. In addition, in 2010 and 2011, we won several contracts with a transit agency in California that have significant volume but smaller margins than we typically generate on our fuel sales. As a result of all of these factors, the overall average margin on our fuel sales across our business decreased in 2011.

We believe that our margins on fuel sales will improve in the future to the extent we are successful in increasing our retail CNG and LNG fueling operations, which is where we earn our highest margins. If our retail CNG and LNG fueling operations do not grow, we may experience further reduced margins. We may also lose contracts with governmental customers if we are unwilling or unable to reduce our prices or lose in the competitive bidding process, which would reduce our volumes. We will need to increase our business with non-government entities to replace volumes lost in competitive bid procurements when we are not successful in retaining the contracts.

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During 2012 and the first three months in 2013, prices for oil, gasoline, and diesel fuel were generally substantially higher than the price for natural gas. Oil hit a high of $107.07 in February 2012 and settled at $97.23 per barrel on March 31, 2013. In California, average retail prices for gasoline were $3.68 per gallon in January 2012, hit a high of $4.71 per gallon in October 2012, and settled at $4.11 per gallon at March 31, 2013. Average retail prices for diesel fuel in California were $4.05 per diesel gallon in January 2012, hit a high of $4.50 per diesel gallon in September 2012, and settled at $4.15 per diesel gallon at March 31, 2013. Higher gasoline and diesel prices improve our margins on fuel sales to the extent we price our fuel at a discount to gasoline or diesel and natural gas prices do not increase by a corresponding amount. During this time period, the price for natural gas increased slightly. The NYMEX price for natural gas fluctuated from $3.08 per MMbtu in January 2012 to $3.71 per MMbtu in December 2012, and settled at $3.43 per MMbtu in March 2013. The average retail sales price of our CNG fuel sold in the Los Angeles metropolitan area ranged from $2.75 per gallon for the month of January 2012 to $2.90 per gallon for the month of March 2013. The average retail sales price of our LNG fuel sold in the Los Angeles metropolitan area ranged from $2.48 per gallon during January 2012 to $2.70 per gallon for the month of March 2013.

Recent developments.  In January 2013, certain federal fuel tax credits were extended through December 31, 2013 and made retroactive to January 1, 2012. The amount attributed to 2012, $20.8 million, has been recorded by us in the first quarter of 2013, the period in which the law was passed. In March 2013, we sold our ownership interest in our joint venture in Peru for approximately $6.1 million after receiving a dividend distribution of approximately $1.1 million (see note 9 to our condensed consolidated financial statements). In January and February 2013, an aggregate of $4.0 million of principal and accrued interest under an SLG Note (as defined and discussed elsewhere in this Item 2 and in note 12 to our condensed consolidated financial statements) was converted by the holder into 268,664 shares of our common stock.