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As filed with the Securities and Exchange Commission on July 11, 2008

Registration No. 333-            

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UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

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FORM S-3
REGISTRATION STATEMENT
UNDER
THE SECURITIES ACT OF 1933

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Clean Energy Fuels Corp.
(Exact Name of Registrant as Specified in Its Charter)

Delaware (State or Other Jurisdiction of Incorporation or Organization)

3020 Old Ranch Parkway, Suite 200 Seal Beach, California 90740 (562) 493-2804 (Address, Including Zip Code, and Telephone Number, Including Area Code, of Registrant's Principal Executive Offices)

33-0968580 (I.R.S. Employer Identification Number)

Andrew J. Littlefair
President and Chief Executive Officer
Clean Energy Fuels Corp.
3020 Old Ranch Parkway, Suite 200
Seal Beach, California 90740
(562) 493-2804
(Name, Address, Including Zip Code, and Telephone Number, Including Area Code, of Agent for Service)

Copies To:
John J. Hentrich, Esq.
Robert L. Wernli, Jr., Esq.
Sheppard, Mullin, Richter & Hampton LLP
12275 El Camino Real, Suite 200
San Diego, California 92130-2006
(858) 720-8900

           Approximate Date of Commencement of Proposed Sale to the Public: From time to time after this registration statement becomes effective.

           If the only securities being registered on this Form are being offered pursuant to dividend or interest reinvestment plans, please check the following box:    o

           If any of the securities being registered on this Form are to be offered on a delayed or continuous basis pursuant to Rule 415 under the Securities Act of 1933, other than securities offered only in connection with dividend or interest reinvestment plans, check the following box:    ý

           If this Form is filed to register additional securities for an offering pursuant to Rule 462(b) under the Securities Act, please check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering.    o

           If this Form is a post-effective amendment filed pursuant to Rule 462(c) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering.    o

           If this Form is a registration statement pursuant to General Instruction I.D. or a post-effective amendment thereto that shall become effective upon filing with the Commission pursuant to Rule 462(e) under the Securities Act, check the following box.    o

           If this Form is a post-effective amendment to a registration statement filed pursuant to General Instruction I.D. filed to register additional securities or additional classes of securities pursuant to Rule 413(b) under the Securities Act, check the following box.    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 the definitions of "large accelerated filer," "accelerated filer" and "smaller reporting company" in Rule 12b-2 of the Exchange Act.

Large accelerated filer o

Accelerated filer o

Non-accelerated filer ý (Do not check if a smaller reporting company)

Smaller reporting company o

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CALCULATION OF REGISTRATION FEE

Title of Each Class of Securities to be Registered			Amount to be Registered(1)		Proposed Maximum Offering Price Per Unit(1)		Proposed Maximum Aggregate Offering Price(1)(2)		Amount of Registration Fee(3)(4)
Preferred Stock, par value $0.0001 per share
Common Stock, par value $0.0001 per share
Warrants
	Total						$150,000,000		$5,895

(1)

The amount to be registered, proposed maximum offering price per unit, and proposed maximum aggregate offering price are not being specified for each class of securities being registered pursuant to General Instruction II.D. to Form S-3 and Rule 457(o). The registrant will determine such amounts from time to time in connection with the issuance by the registrant of the securities registered hereunder.

(2)

This registration statement registers an indeterminate number of shares of preferred stock, shares of common stock and warrants as shall have an aggregate initial offering price not to exceed $150,000,000 that the registrant may sell from time to time, including any consideration which may be received for securities which are issuable upon the conversion, exchange or exercise of other securities. Such amount represents the offering price of any shares of preferred stock, shares of common stock or warrants. Any securities registered hereunder may be sold separately or as units with other securities registered hereunder. Pursuant to Rule 457(i) under the Securities Act of 1933, the securities being registered hereunder include such currently indeterminate number of shares of preferred stock, shares of common stock and warrants as may be issuable by the registrant upon the conversion or exchange of preferred stock that provide for conversion or exchange, or upon the exercise of warrants. Separate consideration may or may not be received for securities that are issuable upon the conversion, exchange or exercise of other securities. In accordance with Rule 416 under the Securities Act, this registration statement shall be deemed to cover any additional securities that may from time to time be offered or issued to prevent dilution resulting from stock splits, stock dividends or similar transactions.

(3)

Estimated solely for purposes of determining the registration fee pursuant to Rule 457(o) of the Securities Act.

(4)

No payment of registration fee is being made in connection with the filing of this registration statement. Rather, $5,895 of the registration fee for this registration statement is being offset, pursuant to Rule 457(p) under the Securities Act, by the registration fees paid in connection with unsold securities registered by the registrant under Registration Statement No. 333-137124 (initially filed on September 6, 2006).

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           The registrant hereby amends this registration statement on such date or dates as may be necessary to delay its effective date until the registrant shall file a further amendment that specifically states that this registration statement shall thereafter become effective in accordance with Section 8(a) of the Securities Act of 1933, as amended, or until this registration statement shall become effective on such date as the Securities and Exchange Commission, acting pursuant to said Section 8(a), may determine.

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PRELIMINARY PROSPECTUS
SUBJECT TO COMPLETION, DATED JULY 11, 2008

The information in this prospectus is not complete and may be changed. We may not sell these securities until the registration statement filed with the Securities and Exchange Commission is effective. This prospectus is not an offer to sell these securities and it is not soliciting an offer to buy these securities in any state where the offer or sale is not permitted.

$150,000,000

PREFERRED STOCK
COMMON STOCK
WARRANTS

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        We may offer and sell any combination of the securities described in this prospectus from time to time in one or more offerings, in one or more series and in amounts, at prices and on terms that we will determine at the time of the offering, up to an aggregate dollar amount of $150,000,000. We will provide the specific terms of the securities, including their offering prices and terms, and the methods by which we will sell them, in supplements to this prospectus. We may offer and sell the securities on an immediate, continuous or delayed basis directly to investors or through underwriters, dealers or agents, or through a combination of these methods. If we use agents, underwriters or dealers to sell any securities, we will name them and describe their compensation in the applicable prospectus supplement.

        The prospectus supplements may also add, update or change other information contained in this prospectus. You should read this prospectus, the applicable prospectus supplement and the documents incorporated by reference in this prospectus and any prospectus supplements carefully before you make your investment decision.

        Our common stock is traded on the NASDAQ Global Market under the symbol "CLNE." On July 11, 2008, the last reported sale price for our common stock on the NASDAQ Global Market was $12.92 per share. Each prospectus supplement will indicate if the securities offered thereby will be listed on any securities exchange.

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        Our business and an investment in our securities involve significant risks. You should read the section entitled "Risk Factors" on page 3 of this prospectus and the risk factors incorporated by reference into this prospectus as described in that section before investing in our securities.

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        Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or passed upon the adequacy or accuracy of this prospectus. Any representation to the contrary is a criminal offense.

        This prospectus may not be used to sell securities unless accompanied by a prospectus supplement which will describe the method and terms of the offering, including the specific plan of distribution.

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The date of this prospectus is                        , 2008

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TABLE OF CONTENTS

		Page
Prospectus Summary		1
Risk Factors		3
Special Note Regarding Forward-Looking Statements		3
Use of Proceeds		4
Description of Securities		4
Description of Capital Stock		4
Description of Warrants		7
Plan of Distribution		11
Where You Can Find Additional Information		13
Information Incorporated by Reference		13
Legal Matters		14
Experts		14

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        In this prospectus and any accompanying prospectus supplement, unless otherwise indicated or the context otherwise requires, references to "Clean Energy" refers to Clean Energy Fuels Corp., and references to "our company," "we," "us," or "our" refers to Clean Energy and its consolidated subsidiaries.

        You should rely only on the information contained or incorporated by reference in this prospectus and any prospectus supplement. We have not authorized anyone to provide you with different information. If anyone provides you with different or inconsistent information, you should not rely on it. We are not making an offer to sell these securities in any jurisdiction where the offer or sale is not permitted. You should read this prospectus and the accompanying prospectus supplement, including the documents incorporated by reference in this prospectus and accompanying prospectus supplement, when making your investment decision. The information in this prospectus is accurate as of the date on the front cover. You should not assume that the information contained in this prospectus is accurate as of any other date.

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PROSPECTUS SUMMARY

        This summary highlights important features of this offering and the information included or incorporated by reference in this prospectus. This summary does not contain all of the information that you should consider before making a future investment decision with respect to our securities. You should read both this prospectus and the accompanying prospectus supplement carefully, including the "Risk Factors," together with any documents incorporated by reference before investing in securities in this offering. In this prospectus and any accompanying prospectus supplement, unless otherwise indicated or the context otherwise requires, references to "our company," "we," "us," or "our" refer to Clean Energy Fuels Corp. and its consolidated subsidiaries.

Overview

        This prospectus is part of a registration statement that we filed with the Securities and Exchange Commission, or SEC, using a "shelf" registration process. Under this process, we may from time to time offer and sell to the public any or all of the securities described in the registration statement in one or more offerings. This prospectus provides you with a general description of the securities we may offer. Each time we offer to sell any of the securities registered under this prospectus, we will provide a supplement to this prospectus that will contain specific information about the terms of that offering. The prospectus supplement may also add, update or change information contained in this prospectus or in the documents incorporated by reference into this prospectus. If there is any inconsistency between the information in this prospectus and the information in the prospectus supplement, you should rely on the information in the prospectus supplement. It is important for you to consider the information contained in this prospectus and any prospectus supplement together with additional information described under the heading "Where You Can Find Additional Information."

        This prospectus contains summaries of certain provisions contained in some of the documents described herein, but reference is made to the actual documents for complete information. All of the summaries are qualified in their entirety by the actual documents. Copies of some of the documents referred to herein have been filed or will be filed as exhibits to the registration statement of which this prospectus is a part or will be incorporated by reference from a current report on Form 8-K that we file with the SEC, and you may obtain copies of those documents as described below under "Where You Can Find Additional Information."

Our Company

        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 offer a comprehensive solution to enable our customers to run their fleets on natural gas. We design, build, finance and operate fueling stations and supply our customers with CNG and LNG. We also help them acquire and finance natural gas vehicles and obtain local, state and federal clean air rebates and incentives. CNG and LNG are cheaper than gasoline and diesel, and are well suited for use by vehicle fleets that consume high volumes of fuel, refuel at centralized locations, and are increasingly required to reduce emissions. According to the U.S. Department of Energy's Energy Information Administration (EIA), the amount of natural gas consumed in the United States for vehicle use nearly doubled between 2000 and 2007. We believe we are positioned to capture a substantial share of the growth in the use of natural gas as a vehicle fuel in the United States given our leading market share and the comprehensive solutions we offer.

        We sell natural gas vehicle fuels in the form of both CNG and LNG. CNG is generally used in automobiles and other light to medium-duty vehicles as an alternative to gasoline. CNG is produced from natural gas that is supplied by local utilities to CNG vehicle fueling stations, where it is compressed and dispensed into vehicles in gaseous form. LNG is generally used in trucks and other medium to heavy-duty vehicles as an alternative to diesel, typically where a vehicle must carry a greater volume of fuel. LNG is natural gas that is super cooled at a liquefaction facility to -162 degrees

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Celsius (-260 degrees Fahrenheit) until it condenses into a liquid, which takes up about 1/600th of its original volume as a gas. We deliver LNG to fueling stations via our fleet of 60 tanker trailers. At the stations, LNG is stored in above ground containers until dispensed into vehicles in liquid form.

        We serve fleet vehicle operators in a variety of markets, including public transit, refuse hauling, airports, taxis, seaports, and regional trucking. We believe the fleet market will continue to present a high growth opportunity for natural gas vehicle fuels. Some of the largest potential markets are seaports, airports, public transit and refuse hauling. For example, two of the largest seaports in the United States, Los Angeles and Long Beach, together have adopted a plan to mandate the use of alternative fuels for vehicle fleets serving those seaports, and other seaports are also considering alternative fuels. In addition, there is considerable room for growth in our key markets of public transit and refuse hauling, with approximately 19% of public transit buses and approximately 1% of refuse haulers currently using natural gas fuels, as stated by INFORM, Inc., a national nonprofit organization focused on environmental concerns (INFORM), and by the American Public Transportation Association.

        We generate revenues primarily by selling CNG and LNG, and to a lesser extent by building, operating and maintaining CNG and LNG fueling stations. We serve over 275 fleet customers operating over 14,000 natural gas vehicles. We own, operate or supply 170 natural gas fueling stations in Arizona, California, Colorado, Maryland, Massachusetts, Nevada, New Mexico, New York, Texas, Washington, Georgia, Wyoming and Canada. Additionally, we have formed a joint venture that owns and operates a CNG fueling station in Lima, Peru.

        We own and operate an LNG liquefaction plant near Houston, Texas, which we call the Pickens Plant, capable of producing up to 35 million gallons of LNG per year. We are also in the process of building an LNG liquefaction plant in California. We expect this plant will be operational in the fall of 2008, assuming we do not experience significant construction delays. We anticipate this plant will initially be capable of producing up to 60 million gallons of LNG per year, and will be expandable to produce up to 90 million gallons of LNG per year.

Corporate Information

        Our principal executive offices are located at 3020 Old Ranch Parkway, Suite 200, Seal Beach, California 90740, and our main telephone number is (562) 493-2804. Our internet address is www.cleanenergyfuels.com. Except for the documents referred to under "Where You Can Find Additional Information" which are specifically incorporated by reference into this prospectus, information contained on our website or that can be accessed through our website does not constitute a part of this prospectus. We have included our website address only as an interactive textual reference and do not intend it to be an active link to our website.

The Offering

        We may offer any of the following securities from time to time:

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shares of our preferred stock;



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shares of our common stock; or



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warrants to purchase any of the above securities.

        When we use the term securities in this prospectus, we mean any of the securities we may offer with this prospectus from time to time, unless we indicate otherwise. When we issue new securities, we may offer them for sale to or through underwriters, dealers and agents, including our subsidiaries, or directly to purchasers. The applicable prospectus supplement will include any required information about the firms we use and the discounts or commissions we may pay them for their services.

Listing

        The applicable prospectus supplement will specify if any securities are to be listed or quoted on a securities exchange or quotation system. Our common stock is listed on the NASDAQ Global Market and trades under the symbol "CLNE."

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RISK FACTORS

        An investment in our securities involves a high degree of risk. You should carefully consider the risk factors contained in the accompanying prospectus supplement as well as those set forth in our most recent annual report on Form 10-K on file with the SEC, which is incorporated by reference in this prospectus. Before making an investment decision, you should carefully consider these risks as well as other information we include or incorporate by reference in this prospectus and the accompanying prospectus supplement. The risks and uncertainties not presently known to us or that we currently deem immaterial may also materially harm our business, operating results and financial condition and could result in a complete loss of your investment.

SPECIAL NOTE REGARDING FORWARD-LOOKING STATEMENTS

        Certain statements in this prospectus or incorporated by reference herein may constitute "forward-looking" statements within the meaning of Section 27A of the Securities Act of 1933 and Section 21E of the Securities Exchange Act of 1934. Forward-looking statements are based upon current assumptions, expectations and beliefs concerning future developments and their potential effect on our business. These forward-looking statements are not guarantees of future performance and involve risks, uncertainties and assumptions that are difficult to predict. Actual outcomes and results may differ materially from what is expressed or forecast in these forward-looking statements. Factors that might cause or contribute to such differences include, but are not limited to, those discussed in "Risk Factors" above. These forward-looking statements speak only as of the date they were made and we undertake no obligation to publicly update or revise any forward-looking statements, whether as a result of new information, future events or otherwise. Words such as "expects," "intends," "plans," "projects," "believes," "estimates," and similar expressions are used to identify these forward looking statements, but their absence does not mean that a statement is not forward looking. Forward-looking statements in this prospectus or incorporated by reference herein may include, but are not limited to, statements regarding:

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projected capital expenditures and related funding requirements;



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potential acquisitions of complementary businesses in the natural gas fueling industry



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developments and trends in the natural gas vehicle market;



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growth of the market for natural gas vehicle fuels;



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expanded use of natural gas vehicles at the Los Angeles and Long Beach seaports;



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future prices of crude oil, gasoline and diesel compared to natural gas;



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future prices and expanded use of other alternative fuels such as biodiesel or ethanol;



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the impact of environmental regulations on the cost of crude oil, gasoline, diesel and diesel engines;



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the impact of environmental regulations on the use of natural gas as a vehicle fuel;



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future supply, demand and prices for natural gas;



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anticipated completion of our California LNG plant; and



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the availability of tax incentives and grant programs that provide incentives for using natural gas as a vehicle fuel.

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USE OF PROCEEDS

        Unless we specify otherwise in the accompanying prospectus supplement, we currently intend to use the net proceeds from the sale of the securities for general corporate purposes. These purposes may include repayment of debt, repurchase or redemption of our common stock, working capital needs, capital expenditures, acquisitions (particularly in the natural gas fueling infrastructure, service and production industries) and any other general corporate purpose. Pending application of the net proceeds, we may temporarily invest the net proceeds in short-term marketable securities.

        If a material part of the net proceeds is to be used to repay indebtedness, we will set forth the interest rate and maturity of such indebtedness in the accompanying prospectus supplement.

        We may not receive any cash proceeds from the sale of shares of preferred stock, shares of common stock, or warrants pursuant to this prospectus and the accompanying prospectus supplement if we issue the securities as consideration for services performed or goods provided to us, in repayment of outstanding indebtedness, or upon the conversion, exchange or exercise of outstanding securities.

        We may set forth additional information on the use of the net proceeds from the sale of securities we offer under this prospectus in the prospectus supplement relating to the specific offering.

DESCRIPTION OF SECURITIES

        The following description of our preferred stock, common stock and warrants to purchase any of the above securities summarizes the material terms and provisions of these securities. We will describe in the prospectus supplement relating to the offering of any securities the particular terms of the securities being offered by that prospectus supplement. If applicable, we will also include information in the prospectus supplement about material United States federal income tax considerations, if any, relating to the securities, and the securities exchange, if any, on which the securities will be listed. The terms of these securities may also be affected by Delaware law.

DESCRIPTION OF CAPITAL STOCK

        The following summary of the terms of our capital stock is qualified in its entirety by reference to the full text of our certificate of incorporation and bylaws. Stockholders are urged to read our certificate of incorporation and bylaws in their entirety for the actual terms of our capital stock. These documents are filed as exhibits to the registration statement of which this prospectus forms a part. See the section entitled "Where You Can Find Additional Information."

Authorized Capital Stock

        Our authorized capital stock consists of 99,000,000 shares of common stock, par value $0.0001 per share, and 1,000,000 shares of preferred stock, par value $0.0001 per share. As of July 9, 2008, there were 44,309,137 shares of common stock outstanding. As of July 9, 2008, no shares of preferred stock were outstanding.

Common Stock

        Subject to preferences that may apply to shares of preferred stock outstanding at the time, the holders of outstanding shares of our common stock are entitled to receive dividends out of assets legally available at the times and in the amounts that our board of directors may determine from time to time. Upon our liquidation, dissolution or winding-up, the holders of common stock are entitled to share in all assets remaining after payment of all liabilities and the liquidation preferences of any outstanding preferred stock.

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        Each holder of common stock is entitled to one vote for each share of common stock held on all matters submitted to a vote of stockholders. We have not provided for cumulative voting for the election of directors in our certificate of incorporation.

        Our common stock is not entitled to preemptive rights and is not subject to conversion or redemption.

        The transfer agent and registrar for our common stock is Computershare Trust Company, N.A.

        Our common stock is quoted on the NASDAQ Global Market under the trading symbol "CLNE."

Preferred Stock

        Our board of directors is authorized, subject to limitations imposed by Delaware law and NASDAQ rules, to issue up to a total of 1,000,000 shares of preferred stock in one or more series, without further stockholder approval. Our board of directors will be authorized to establish from time to time the number of shares to be included in each series, and to fix the rights, preferences and privileges of the shares of each wholly unissued series and any of its qualifications, limitations or restrictions. Our board of directors is authorized to increase or decrease the number of shares of any series, but not below the number of shares of that series then outstanding, without any further vote or action by the stockholders.

        The board of directors may authorize the issuance of preferred stock with voting or conversion rights that could adversely affect the voting power or other rights of the holders of the common stock. The issuance of preferred stock, while providing flexibility in connection with possible acquisitions and other corporate purposes, could, among other things, have the effect of delaying, deferring or preventing a change in control of our company and might harm the market price of our common stock and the voting and other rights of the holders of common stock.

        A prospectus supplement relating to a series of preferred stock will describe terms of that series of preferred stock, including:

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the designation and stated value of that series;



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the number of shares we are offering;



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the initial public offering price at which the shares will be sold;



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the dividend rate of that series, the conditions and dates upon which those dividends will be payable, whether those dividends will be cumulative or noncumulative, and, if cumulative, the date from which dividends will accumulate;



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the process for any auction and remarketing, if any;



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the relative ranking and preferences of that series as to dividend rights and rights upon any liquidation, dissolution or winding up of the affairs of our company;



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any redemption, repurchase, or sinking fund provisions;



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any conversion or exchange rights of the holder or us;



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any voting rights;



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any preemptive rights;



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any restrictions on transfer, sale or other assignment;



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any restrictions on further issuances;



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whether interests in the preferred stock will be represented by depositary shares;

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a discussion of any material United States federal income tax considerations applicable to the preferred stock;



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any application for listing of that series on any securities exchange or market;



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any limitations on the issuance of any class or series of preferred stock ranking senior to or on a parity with the series of preferred stock as to dividend rights and rights upon liquidation, dissolution or winding up of our company's affairs; and



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any other specific terms, preferences, rights or limitations of, or restrictions on, that series of preferred stock.

Anti-Takeover Effects of Delaware Law and our Certificate of Incorporation and Bylaws

        Certain provisions of Delaware law, our certificate of incorporation and our bylaws contain provisions that could have the effect of delaying, deferring or discouraging another party from acquiring control of us. These provisions, which are summarized below, are expected to discourage coercive takeover practices and inadequate takeover bids. These provisions are also designed to encourage persons seeking to acquire control of us to first negotiate with our board of directors. We believe that the benefits of increased protection of our potential ability to negotiate with an unfriendly or unsolicited acquiror outweigh the disadvantages of discouraging a proposal to acquire us because negotiation of these proposals could result in an improvement of their terms.

Delaware Law

        We are subject to the provisions of Section 203 of the Delaware General Corporation Law regulating corporate takeovers. In general, those provisions prohibit a Delaware corporation from engaging in any business combination with any interested stockholder for a period of three years following the date that the stockholder became an interested stockholder, unless:

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before the date of the transaction, the board approved either the business combination or the transaction which resulted in the stockholder becoming an interested stockholder;



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upon consummation of the transaction that resulted in the stockholder becoming an interested stockholder, the interested stockholder owned at least 85% of the voting stock of the corporation outstanding at the time the transaction commenced, excluding for purposes of determining the number of shares outstanding (1) shares owned by persons who are directors and also officers and (2) shares owned by employee stock plans in which employee participants do not have the right to determine confidentially whether shares held subject to the plan will be tendered in a tender or exchange offer; or



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on or after the date the business combination is approved by the board, the transaction is authorized at a meeting of stockholders by at least two-thirds of the outstanding voting stock that is not owned by the interested stockholder.

        Section 203 defines "business combination" to include the following:

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any merger or consolidation involving the corporation and the interested stockholder;



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any sale, transfer, pledge or other disposition of 10% or more of the assets of the corporation involving the interested stockholder;



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subject to certain exceptions, any transaction that results in the issuance or transfer by the corporation of any stock of the corporation to the interested stockholder;

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any transaction involving the corporation that has the effect of increasing the proportionate share of the stock of any class or series of the corporation beneficially owned by the interested stockholder; or



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the receipt by the interested stockholder of the benefit of any loans, advances, guarantees, pledges or other financial benefits provided by or through the corporation.

        In general, Section 203 defines an interested stockholder as any entity or person beneficially owning 15% or more of the outstanding voting stock of the corporation and any entity or person affiliated with or controlling or controlled by any of these entities or persons.

        A Delaware corporation may opt out of this provision either with an express provision in its original certificate of incorporation or in an amendment to its certificate of incorporation or bylaws approved by its stockholders. However, we have not opted out, and do not currently intend to opt out, of this provision. The statute could prohibit or delay mergers or other takeover or change in control attempts and, accordingly, may discourage attempts to acquire us.

Charter and Bylaws

        In addition, some provisions of our certificate of incorporation and bylaws may be deemed to have an anti-takeover effect and may delay, defer or prevent a tender offer or takeover attempt that a stockholder might deem to be in the stockholder's best interest. The existence of these provisions could limit the price that investors might be willing to pay in the future for shares of our common stock. These provisions include:

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Authorized but unissued shares.  The authorized but unissued shares of common stock and preferred stock are available for future issuance without stockholder approval, subject to certain limitations imposed by NASDAQ. These additional shares may be used for a variety of corporate purposes, such as for acquisitions and employee benefit plans. The existence of authorized but unissued and unreserved common stock and preferred stock could render more difficult or discourage an attempt to obtain control of us by means of a proxy contest, tender offer, merger or otherwise.



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Special meetings of stockholders.  Special meetings of stockholders may only be called by our board of directors or our chief executive officer.



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Amendment to bylaws.  Our board of directors is authorized to make, alter or repeal our bylaws without further stockholder approval.



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Advance notice of director nominations and matters to be acted upon at meetings.  Our bylaws contain advance notice requirements for nominations for directors to our board of directors and for proposing matters that can be acted upon by stockholders at stockholder meetings.

DESCRIPTION OF WARRANTS

        We may issue warrants for the purchase of shares of preferred stock, shares of common stock or any of the above securities in one or more series. We may issue warrants independently or together with shares of preferred stock or shares of common stock, and the warrants may be attached to or separate from these securities. While the terms summarized below will apply generally to any warrants that we may sell, we will describe the particular terms of any series of warrants in more detail in the applicable prospectus supplement. The terms of any warrants offered under a prospectus supplement may differ from the terms described below.

        We will incorporate by reference from reports that we file with the SEC the form of warrant agreement, including a form of warrant certificate, that describes the terms of the particular series of warrants we are offering before the issuance of the related series of warrants. The following summaries

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of material provisions of the warrants and the warrant agreements are subject to, and qualified in their entirety by reference to, all the provisions of the warrant agreement and warrant certificate applicable to the particular series of warrants that we may offer under this prospectus and the accompanying prospectus supplement. We urge you to read the applicable prospectus supplements related to the particular series of warrants that we may offer under this prospectus, as well as any related free writing prospectuses, and the complete warrant agreements and warrant certificates that contain the terms of the warrants.

General

        You should review the applicable prospectus supplement for the specific terms of any warrants that may be offered, including the following:

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the title of the warrants;



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the aggregate number of the warrants;



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the price or prices at which the warrants will be issued;



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the designation, stated value, terms (including liquidation, dividend, conversion and voting rights), number of shares and purchase price per share of the class or series of preferred stock purchasable upon the exercise of warrants to purchase shares of preferred stock;



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the number of shares and the purchase price per share of common stock purchasable upon the exercise of warrants to purchase shares of common stock;



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if applicable, the date on and after which the warrants and the related securities will be separately transferable;



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the effect of any merger, consolidation, sale or other disposition of our business on the warrant agreements and the warrants;



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the terms of any rights to redeem or call the warrants;



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any provisions for changes to or adjustments in the exercise price or number of securities issuable upon exercise of the warrants;



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the date on which the right to exercise the warrants will commence and the date on which the right will expire;



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if applicable, the minimum or maximum number of warrants that may be exercised at any one time;



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the manner in which the warrant agreements and warrants may be modified;



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information relating to book-entry procedures, if any;



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if applicable, a discussion of material United States federal income tax considerations of holding or exercising the warrants; and



•

any other terms of the warrants, including terms, procedures and limitations relating to the exchange and exercise of the warrants.

        Before exercising their warrants, holders of warrants will not have any of the rights of holders of the securities purchasable upon such exercise, including the right to receive dividends, if any, or, payments upon our liquidation, dissolution or winding up or to exercise voting rights, if any.

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Exercise of Warrants

        Each warrant will entitle the holder to purchase the securities that we specify in the applicable prospectus supplement at the exercise price that we describe in the applicable prospectus supplement. Unless we otherwise specify in the applicable prospectus supplement, holders of the warrants may exercise the warrants at any time up to the specified time on the expiration date that we set forth in the applicable prospectus supplement. After the close of business on the expiration date, unexercised warrants will become void.

        Holders of the warrants may exercise the warrants by delivering the warrant certificate representing the warrants to be exercised together with specified information, and paying the required amount to the warrant agent in immediately available funds, as provided in the applicable prospectus supplement. We will set forth on the reverse side of the warrant certificate and in the applicable prospectus supplement the information that the holder of the warrant will be required to deliver to the warrant agent.

        Upon receipt of the required payment and the warrant certificate properly completed and duly executed at the corporate trust office of the warrant agent or any other office indicated in the applicable prospectus supplement, we will issue and deliver the securities purchasable upon such exercise. If fewer than all of the warrants represented by the warrant certificate are exercised, then we will issue a new warrant certificate for the remaining amount of warrants. If we so indicate in the applicable prospectus supplement, holders of the warrants may surrender securities as all or part of the exercise price for warrants.

Enforceability of Rights By Holders of Warrants

        Each series of warrants will be issued under a separate warrant agreement to be entered into between a warrant agent and us. Each warrant agent will act solely as our agent under the applicable warrant agreement and will not assume any obligation or relationship of agency or trust with any holder of any warrant. A single bank or trust company may act as warrant agent for more than one issue of warrants. A warrant agent will have no duty or responsibility in case of any default by us under the applicable warrant agreement or warrant, including any duty or responsibility to initiate any proceedings at law or otherwise, or to make any demand upon us. Any holder of a warrant may, without the consent of the related warrant agent or the holder of any other warrant, enforce by appropriate legal action its right to exercise, and receive the securities purchasable upon exercise of, its warrants.

Amendments and Supplements to the Warrant Agreements

        We may amend or supplement a warrant agreement without the consent of the holders of the applicable warrants to cure ambiguities in the warrant agreement, to cure or correct a defective provision in the warrant agreement, or to provide for other matters under the warrant agreement that we and the warrant agent deem necessary or desirable, so long as, in each case, such amendments or supplements do not materially adversely affect the interests of the holders of the warrants.

Warrant Adjustments

        Unless the applicable prospectus supplement states otherwise, the exercise price of, and the number of securities covered by, a warrant to purchase shares of preferred stock or common stock will

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be adjusted proportionately if we subdivide or combine our preferred stock or common stock, as applicable. In addition, unless the prospectus supplement states otherwise, if we, without payment:

•

issue capital stock or other securities convertible into or exchangeable for preferred stock or common stock, or any rights to subscribe for, purchase or otherwise acquire either class of capital stock, as a dividend or distribution to holders of our preferred stock or common stock;



•

pay any cash to holders of our preferred stock or common stock other than a cash dividend paid out of our current or retained earnings or other than in accordance with the terms of the preferred stock;



•

issue any evidence of our indebtedness or rights to subscribe for or purchase our indebtedness to holders of our preferred stock or common stock; or



•

issue preferred stock or common stock or additional stock or other securities or property to holders of our preferred stock or common stock by way of spinoff, split-up, reclassification, combination of shares or similar corporate rearrangement,

then the holders of preferred stock or common stock warrants, as applicable, will be entitled to receive upon exercise of the warrants, in addition to the securities otherwise receivable upon exercise of the warrants and without paying any additional consideration, the amount of stock and other securities and property those holders would have been entitled to receive had they held the preferred stock or common stock, as applicable, issuable under the warrants on the dates on which holders of those securities received or became entitled to receive the additional stock and other securities and property.

        Except as stated above, the exercise price and number of securities covered by a preferred stock or common stock warrant, and the amounts of other securities or property to be received, if any, upon exercise of those warrants, will not be adjusted or provided for if we issue those securities or any securities convertible into or exchangeable for those securities, or securities carrying the right to purchase those securities or securities convertible into or exchangeable for those securities.

        Holders of preferred stock or common stock warrants may have additional rights under the following circumstances:

•

certain reclassifications, capital reorganizations or changes of the preferred stock or common stock, as applicable;



•

certain share exchanges, mergers, or similar transactions involving our company and which result in changes of the preferred stock or common stock, as applicable; or



•

certain sales or dispositions to another entity of all or substantially all of our property and assets.

        If one of the above transactions occurs and holders of our preferred stock or common stock are entitled to receive stock, securities or other property with respect to or in exchange for their securities, the holders of the preferred stock or common stock warrants then outstanding, as applicable, will be entitled to receive upon exercise of their warrants the kind and amount of shares of stock and other securities or property that they would have received upon the applicable transaction if they had exercised their warrants immediately before the transaction.

Currently Outstanding Warrants

        In December 2006, we issued to Boone Pickens, a director and our largest stockholder, a warrant to purchase 15,000,000 shares of common stock at an exercise price of $10.00 per share. The warrant is fully exercisable in whole or in part by cash payment of the exercise price and expires five years following the date of grant.

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PLAN OF DISTRIBUTION

        We may sell the securities in one or more of the following ways from time to time:

•

to or through underwriters or dealers;



•

directly to one or more purchasers;



•

through agents; or



•

through a combination of any of these methods of sale.

        We may effect the distribution of the securities from time to time in one or more transactions either:

•

at a fixed price or prices which may be changed;



•

at market prices prevailing at the time of sale;



•

at prices relating to such prevailing market prices; or



•

at negotiated prices.

        The prospectus supplements relating to an offering of offered securities will set forth the terms of such offering, including:

•

the name or names of any underwriters, dealers or agents;



•

the purchase price of the offered securities and the proceeds we will receive from the sale;



•

any underwriting discounts and commissions or agency fees and other items constituting underwriters' or agents' compensation; and



•

any initial public offering price, any discounts or concessions allowed or reallowed or paid to dealers and any securities exchanges on which such offered securities may be listed.

        We may grant underwriters who participate in the distribution of securities an option to purchase additional securities to cover over-allotments, if any, in connection with the distribution.

        Underwriters, dealers or agents may receive compensation in the form of discounts, concessions or commissions from us or our purchasers, as their agents in connection with the sale of securities. These underwriters, dealers or agents may be considered to be underwriters under the Securities Act. As a result, discounts, commissions or profits on resale received by the underwriters, dealers or agents may be treated as underwriting discounts and commissions. The prospectus supplement will identify any such underwriter, dealer or agent and describe any compensation received by them from us.

        Any initial public offering prices, discounts or concessions allowed or reallowed or paid to dealers may be changed from time to time.

        If underwriters are used in the sale, the underwriters will acquire the offered securities for their own account and may resell them from time to time in one or more transactions, including negotiated transactions, at a fixed public offering price or at varying prices determined at the time of sale. The offered securities may be offered either to the public through underwriting syndicates represented by one or more managing underwriters or by one or more underwriters without a syndicate. Unless otherwise set forth in a prospectus supplement, the obligations of the underwriters to purchase any series of securities will be subject to certain conditions precedent, and the underwriters will be obligated to purchase all of such series of securities, if any are purchased.

        We may authorize underwriters, dealers or agents to solicit offers by certain purchasers to purchase the securities from us at the public offering price set forth in the prospectus supplement pursuant to delayed delivery contracts providing for payment and delivery on a specified date in the

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future. The contracts will be subject only to those conditions set forth in the prospectus supplement, and the prospectus supplement will set forth any commissions we pay for solicitation of these contracts.

        We may enter into derivative transactions with third parties, or sell securities not covered by this prospectus to third parties in privately negotiated transactions. If the applicable prospectus supplement indicates, in connection with those derivatives, the third parties may sell securities covered by this prospectus and the applicable prospectus supplement, including in short sale transactions. If so, the third party may use securities pledged by us or borrowed from us or others to settle those sales or to close out any related open borrowings of stock, and may use securities received from us in settlement of those derivatives to close out any related open borrowings of stock. The third party in such sale transactions will be an underwriter and will be identified in the applicable prospectus supplement or in a post-effective amendment.

        In connection with underwritten offerings of the offered securities and in accordance with applicable law and industry practice, underwriters may over-allot or effect transactions that stabilize, maintain or otherwise affect the market price of the offered securities at levels above those that might otherwise prevail in the open market in accordance with Regulation M under the Exchange Act, including by entering stabilizing bids, effecting syndicate covering transactions or imposing penalty bids, each of which is described below.

•

A stabilizing bid means the placing of any bid, or the effecting of any purchase, for the purpose of pegging, fixing or maintaining the price of a security.



•

A syndicate covering transaction means the placing of any bid on behalf of the underwriting syndicate or the effecting of any purchase to reduce a short position created in connection with the offering.



•

A penalty bid means an arrangement that permits the managing underwriter to reclaim a selling concession from a syndicate member in connection with the offering when offered securities originally sold by the syndicate member are purchased in syndicate covering transactions.

        Those activities may cause the price of the securities to be higher than it would otherwise be. If commenced, the underwriters may discontinue any of the activities at any time. We make no representation or prediction as to the direction or magnitude of any effect that such transactions may have on the price of the securities. For a description of these activities, see the information under the heading "Underwriting" in the applicable prospectus supplement.

        These transactions may be effected on the NASDAQ Global Market, in the over-the-counter market, or otherwise. Underwriters are not required to engage in any of these activities, or to continue such activities if commenced.

        If a dealer is used in the sale, we will sell such offered securities to the dealer, as principal. The dealer may then resell the offered securities to the public at varying prices to be determined by that dealer at the time for resale. The names of the dealers and the terms of the transaction will be set forth in the prospectus supplement relating to that transaction.

        Offered securities may be sold directly by us to one or more institutional purchasers, or through agents designated by us from time to time, at a fixed price or prices, which may be changed, or at varying prices determined at the time of sale. Any agent involved in the offer or sale of the offered securities in respect of which this prospectus is delivered will be named, and any commissions payable by us to such agent will be set forth, in the prospectus supplement relating to that offering. Unless otherwise indicated in such prospectus supplement, any such agent will be acting on a best efforts basis for the period of its appointment.

        Underwriters, dealers and agents may be entitled under agreements entered into with us to indemnification by us against certain civil liabilities, including liabilities under the Securities Act, or to

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contribution with respect to payments that the underwriters, dealers or agents may be required to make in respect thereof. Underwriters, dealers and agents may be customers of, engage in transactions with, or perform services for us and our affiliates in the ordinary course of their business for which they receive compensation.

        Unless otherwise specified in the related prospectus supplement, all securities we offer, other than common stock, will be a new issue of securities, will have no prior trading market, and may or may not be listed on a national securities exchange. Any underwriters to whom we sell securities for public offering and sale may make a market in the securities, but such underwriters will not be obligated to do so and may discontinue any market making at any time without notice. Any shares of common stock sold pursuant to a prospectus supplement will be included in the NASDAQ Global Market. We may apply to list any series of shares of preferred stock or warrants on a securities exchange, but we are not obligated to do so. Therefore, there may not be liquidity or a trading market for any series of securities.

WHERE YOU CAN FIND ADDITIONAL INFORMATION

        We file annual, quarterly and current reports, proxy statements and other information with the SEC as required by the Exchange Act. You can find, copy and inspect information we file with the SEC (including exhibits to such documents) at the SEC's Public Reference Room at 100 F Street, N.E., Room 1580, Washington, D.C. 20549. You may obtain additional information about the Public Reference Room by calling the SEC at 1-800-SEC-0330. In addition, the SEC maintains a site on the internet at http://www.sec.gov/ that contains reports, proxy statements and other information that we file electronically with the SEC. You may also review such reports, proxy statements and other documents we file with the SEC on our website at http://www.cleanenergyfuels.com/. Information included on our website is not a part of this prospectus.

        This prospectus is part of a registration statement that we filed with the SEC. The registration statement contains more information than this prospectus regarding the securities and us, including exhibits and schedules. You can obtain a copy of the registration statement from the SEC at any address listed above or from the SEC's website.

INFORMATION INCORPORATED BY REFERENCE

        We are "incorporating by reference" information into this prospectus. This means that we are disclosing important information to you by referring you to another document that has been filed separately with the SEC. The information incorporated by reference is considered to be part of this prospectus, and information that we file later with the SEC will automatically update and supersede the information contained in documents filed earlier with the SEC or contained in this prospectus. We incorporate by reference into this prospectus the documents listed below and any future filings made by us with the SEC under Section 13(a), 13(c), 14 and 15(d) of the Exchange Act after the initial filing of this registration statement that contains this prospectus and prior to the time that we or the underwriters sell all of the securities offered by this prospectus or the earlier termination of the offering (except in each case the information contained in such documents to the extent "furnished" and not "filed"):

•

Annual Report on Form 10-K for the fiscal year ended December 31, 2007, filed on March 19, 2008;



•

Quarterly Report on Form 10-Q for the quarter ended March 31, 2008, filed on May 15, 2008;



•

Current Reports on Form 8-K filed on April 7, 2008, June 20, 2008 and July 3, 2008; and



•

The description of our common stock which is contained in the Registration Statement on Form 8-A filed with the SEC on May 18, 2007.

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        You may obtain copies, without charge, of documents incorporated by reference in this prospectus, by requesting them in writing or by telephone from us as follows: Clean Energy Fuels Corp., Attn: Investor Relations, 3020 Old Ranch Parkway, Suite 200, Seal Beach, California 90740, (562) 493-2804. Exhibits to the filings will not be sent, unless those exhibits have been specifically incorporated by reference in this prospectus.

LEGAL MATTERS

        Except as set forth in the applicable prospectus supplement, Sheppard, Mullin, Richter & Hampton LLP, San Diego, California, will pass upon certain legal matters in connection with the securities for us. Underwriters, dealers or agents, whom we will identify in a prospectus supplement, may have their counsel opine about certain legal matters relating to the securities.

EXPERTS

        Our consolidated financial statements and schedule as of December 31, 2007 and 2006, and for each of the years in the three-year period ended December 31, 2007, have been incorporated by reference herein and in the registration statement in reliance upon the report of KPMG LLP, independent registered public accounting firm, incorporated by reference herein, and upon the authority of said firm as experts in auditing and accounting.

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PART II

INFORMATION NOT REQUIRED IN PROSPECTUS

Item 14.    Other Expenses of Issuance and Distribution

        The following table sets forth the estimated fees and expenses, other than underwriting discounts and commissions, expected to be incurred in connection with the offering or offerings described in this registration statement.

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(*)

Estimated pursuant to Rule 511 of Regulation S-K.

Item 15.    Indemnification of Directors and Officers

        Section 145 of the Delaware General Corporation Law provides for the indemnification of officers, directors and other corporate agents in terms sufficiently broad to indemnify such persons under certain circumstances for liabilities (including reimbursement for expenses incurred) arising under the Securities Act. Article 7 of the registrant's Amended and Restated Certificate of Incorporation and Article VIII of the registrant's Amended and Restated Bylaws provide for indemnification of the registrant's directors, officers, employees and other agents to the extent and under the circumstances permitted by the Delaware General Corporation Law.

        As permitted by Delaware law, the registrant also has entered into indemnification agreements with each of its directors and officers that require the registrant to indemnify such persons, to the fullest extent authorized or permitted under Delaware law, against any and all costs and expenses (including attorneys', witness or other professional fees) actually and reasonably incurred by such persons in connection with the investigation, defense, settlement or appeal of any action, hearing, suit or other proceeding, whether pending, threatened or completed, to which any such person may be made a witness or a party by reason of (1) the fact that such person is or was a director, officer, employee or agent of the registrant or its subsidiaries, whether serving in such capacity or otherwise acting at the request of the registrant or its subsidiaries, and (2) anything done or not done, or alleged to have been done or not done, by such person in that capacity. The indemnification agreements also require the registrant to advance expenses incurred by directors and officers within 20 days after receipt of a written request, provided that such persons undertake to repay such amounts if it is ultimately determined that they are not entitled to indemnification. Additionally, the agreements set forth certain procedures that will apply in the event of a claim for indemnification thereunder, including a presumption that directors and officers are entitled to indemnification under the agreements, and that the registrant has the burden of proof to overcome that presumption in reaching any contrary determination. The registrant is not required to provide indemnification under the agreements for certain matters, including: (1) indemnification beyond that permitted by Delaware law; (2) indemnification for liabilities for which the officer or director is reimbursed pursuant to such insurance as may exist for such person's benefit; (3) indemnification related to disgorgement of profits under Section 16(b) of the Exchange Act; (4) in connection with certain proceedings initiated against

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the registrant by the director or officer; or (5) indemnification for settlements the director or officer enters into without the registrant's written consent. The indemnification agreements require us to maintain directors' and officers' insurance in full force and effect while any director or officer continues to serve in such capacity, and so long as any such person may incur costs and expenses related to legal proceedings as described above.

Item 16.    Exhibits

        A list of exhibits filed herewith is contained in the exhibit index that immediately precedes such exhibits and is incorporated herein by reference.

Item 17.    Undertakings

        (a)   The undersigned registrant hereby undertakes:

        (1)   To file, during any period in which offers or sales are being made, a post-effective amendment to this registration statement:

        (i)    To include any prospectus required by section 10(a)(3) of the Securities Act of 1933;.

        (ii)   To reflect in the prospectus any facts or events arising after the effective date of the registration statement (or the most recent post-effective amendment thereof) which, individually or in the aggregate, represent a fundamental change in the information set forth in the registration statement. Notwithstanding the foregoing, any increase or decrease in volume of securities offered (if the total dollar value of securities offered would not exceed that which was registered) and any deviation from the low or high end of the estimated maximum offering range may be reflected in the form of prospectus filed with the Commission pursuant to Rule 424(b) if, in the aggregate, the changes in volume and price represent no more than 20 percent change in the maximum aggregate offering price set forth in the "Calculation of Registration Fee" table in the effective registration statement.

        (iii)  To include any material information with respect to the plan of distribution not previously disclosed in the registration statement or any material change to such information in the registration statement;

Provided, however, That paragraphs (a)(1)(i), (a)(1)(ii) and (a)(1)(iii) of this section do not apply if the information required to be included in a post-effective amendment by those paragraphs is contained in reports filed with or furnished to the Commission by the registrant pursuant to section 13 or section 15(d) of the Securities Exchange Act of 1934 that are incorporated by reference in the registration statement, or is contained in a form of prospectus filed pursuant to Rule 424(b) that is part of the registration statement.

        (2)   That, for the purpose of determining any liability under the Securities Act of 1933, each such post-effective amendment shall be deemed to be a new registration statement relating to the securities offered therein, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof.

        (3)   To remove from registration by means of a post-effective amendment any of the securities being registered which remain unsold at the termination of the offering.

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        (4)   That, for the purpose of determining liability under the Securities Act of 1933 to any purchaser:

        (i)    If the registrant is relying on Rule 430B:

        (A)  Each prospectus filed by the registrant pursuant to Rule 424(b)(3) shall be deemed to be part of the registration statement as of the date the filed prospectus was deemed part of and included in the registration statement; and

        (B)  Each prospectus required to be filed pursuant to Rule 424(b)(2), (b)(5) or (b)(7) as part of a registration statement in reliance on Rule 430B relating to an offering made pursuant to Rule 415(a)(1)(i), (vii) or (x) for the purpose of providing the information required by Section 10(a) of the Securities Act of 1933 shall be deemed to be part of and included in the registration statement as of the earlier of the date such form of prospectus is first used after effectiveness or the date of the first contract of sale of securities in the offering described in the prospectus. As provided in Rule 430B, for liability purposes of the issuer and any person that is at that date an underwriter, such date shall be deemed to be a new effective date of the registration statement relating to the securities in the registration statement to which the prospectus relates, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof. Provided, however, that no statement made in a registration statement or prospectus that is part of the registration statement or made in a document incorporated or deemed incorporated by reference into the registration statement or prospectus that is part of the registration statement will, as to a purchaser with a time of contract of sale prior to such effective date, supersede or modify any statement that was made in the registration statement or prospectus that was part of the registration statement or made in any such document immediately prior to such effective date.

        (ii)   If the registrant is subject to Rule 430C, each prospectus filed pursuant to Rule 424(b) as part of a registration statement relating to an offering, other than registration statements relying on Rule 430B or other than prospectuses filed in reliance on Rule 430A, shall be deemed to be part of and included in the registration statement as of the date it is first used after effectiveness. Provided, however, that no statement made in a registration statement or prospectus that is part of the registration statement or made in a document incorporated or deemed incorporated by reference into the registration statement or prospectus that is part of the registration statement will, as to a purchaser with a time of contract of sale prior to such first use, supersede or modify any statement that was made in the registration statement or prospectus that was part of the registration statement or made in any such document immediately prior to such date of first use.

        (5)   That, for the purpose of determining liability of the registrant under the Securities Act of 1933 to any purchaser in the initial distribution of the securities: The undersigned registrant undertakes that in a primary offering of securities of the undersigned registrant pursuant to this registration statement, regardless of the underwriting method used to sell the securities to the purchaser, if the securities are offered or sold to such purchaser by means of any of the following communications, the undersigned registrant will be a seller to the purchaser and will be considered to offer or sell such securities to such purchaser:

        (i)    Any preliminary prospectus or prospectus of the undersigned registrant relating to the offering required to be filed pursuant to Rule 424;

        (ii)   Any free writing prospectus relating to the offering prepared by or on behalf of the undersigned registrant or used or referred to by the undersigned registrant;

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        (iii)  The portion of any other free writing prospectus relating to the offering containing material information about the undersigned registrant or its securities provided by or on behalf of the undersigned registrant; and

        (iv)  Any other communication that is an offer in the offering made by the undersigned registrant to the purchaser.

        (b)   The undersigned registrant hereby undertakes that, for purposes of determining any liability under the Securities Act of 1933, each filing of the registrant's annual report pursuant to Section 13(a) or Section 15(d) of the Securities Exchange Act of 1934 (and, where applicable, each filing of an employee benefit plan's annual report pursuant to Section 15(d) of the Securities Exchange Act of 1934) that is incorporated by reference in the registration statement shall be deemed to be a new registration statement relating to the securities offered therein, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof.

        (c)   That:

        (i)    For purposes of determining any liability under the Securities Act of 1933, the information omitted from the form of prospectus filed as part of this registration statement in reliance upon Rule 430A and contained in a form of prospectus filed by the registrant pursuant to Rule 424(b) (1) or (4) or 497(h) under the Securities Act shall be deemed to be part of this registration statement as of the time it was declared effective.

        (ii)   For the purpose of determining any liability under the Securities Act of 1933, each post-effective amendment that contains a form of prospectus shall be deemed to be a new registration statement relating to the securities offered therein, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof.

        Insofar as indemnification for liabilities arising under the Securities Act of 1933 may be permitted to directors, officers and controlling persons of the registrant pursuant to the foregoing provisions, or otherwise, the registrant has been advised that in the opinion of the Securities and Exchange Commission such indemnification is against public policy as expressed in the Act and is, therefore, unenforceable. In the event that a claim for indemnification against such liabilities (other than the payment by the registrant of expenses incurred or paid by a director, officer or controlling person of the registrant in the successful defense of any action, suit or proceeding) is asserted by such director, officer or controlling person in connection with the securities being registered, the registrant will, unless in the opinion of its counsel the matter has been settled by controlling precedent, submit to a court of appropriate jurisdiction the question whether such indemnification by it is against public policy as expressed in the Act and will be governed by the final adjudication of such issue.

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SIGNATURES

        Pursuant to the requirements of the Securities Act of 1933, the registrant certifies that it has reasonable grounds to believe that it meets all of the requirements for filing on Form S-3 and has duly caused this registration statement to be signed on its behalf by the undersigned, thereunto duly authorized, in the City of Seal Beach, State of California, on this 11th day of July, 2008.

		CLEAN ENERGY FUELS CORP.
		By:		/s/  ANDREW J. LITTLEFAIR       Andrew J. Littlefair President and Chief Executive Officer

        Pursuant to the requirements of the Securities Act of 1933, as amended, this registration statement has been signed by the following persons in their capacities and on the date indicated.

Signature		Title		Date
/s/  ANDREW J. LITTLEFAIR       Andrew J. Littlefair		Director, Chief Executive Officer and President (Principal Executive Officer)		July 11, 2008
/s/  RICHARD R. WHEELER       Richard R. Wheeler		Chief Financial Officer (Principal Financial Officer and Principal Accounting Officer)		July 11, 2008
Directors:
Warren I. Mitchell John S. Herrington James C. Miller III Boone Pickens Kenneth M. Socha Vincent C. Taormina

By:

/s/  ANDREW J. LITTLEFAIR       Andrew J. Littlefair Attorney-in-Fact

July 11, 2008

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EXHIBIT INDEX

        The following documents are filed as exhibits to this registration statement:

Exhibit No.		Description		Filed Herewith		Incorporated by Reference to
1.1		Form of Underwriting Agreement				*
4.1		Restated Certificate of Incorporation				Exhibit 3.1 to Registration Statement on Form S-1, File No. 333-137124 filed on March 27, 2007
4.2		Amended and Restated Bylaws				Exhibit 3.2 to Registration Statement on Form S-1, File No. 333-137124 filed on March 27, 2007
4.3		Form of Common Stock Certificate				Exhibit 4.1 to Registration Statement on Form S-1, File No. 333-137124 filed on March 27, 2007
4.4		Form of Preferred Stock Certificate		×
4.5		Form of Certificate of Designations				*
4.10		Form of Warrant Agreement				*
4.11		Form of Warrant Certificate				*
5.1		Form of Legal Opinion of Sheppard, Mullin, Richter & Hampton LLP(1)		×
12.1		Computation of Ratio/Deficiency of Earnings to Fixed Charges				*
23.1		Consent of KPMG LLP		×
23.2		Consent of Sheppard, Mullin, Richter & Hampton LLP (included in Exhibit 5.1)		×
24.1		Power of Attorney		×

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(1)

The actual legal opinion will be filed by amendment hereto, or as an exhibit to a report filed pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 and incorporated herein by reference, prior to effectiveness.

*

To be filed by amendment hereto or as an exhibit to a report filed pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 and incorporated herein by reference.

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QuickLinks

TABLE OF CONTENTS
PROSPECTUS SUMMARY
RISK FACTORS
SPECIAL NOTE REGARDING FORWARD-LOOKING STATEMENTS
USE OF PROCEEDS
DESCRIPTION OF SECURITIES
DESCRIPTION OF CAPITAL STOCK
DESCRIPTION OF WARRANTS
PLAN OF DISTRIBUTION
WHERE YOU CAN FIND ADDITIONAL INFORMATION
INFORMATION INCORPORATED BY REFERENCE
LEGAL MATTERS
EXPERTS
PART II INFORMATION NOT REQUIRED IN PROSPECTUS

Item 14. Other Expenses of Issuance and Distribution
Item 15. Indemnification of Directors and Officers
Item 16. Exhibits
Item 17. Undertakings

SIGNATURES
EXHIBIT INDEX