SUBSCRIPTION AGREEMENT

Exhibit 99.3

SUBSCRIPTION AGREEMENT

THIS SUBSCRIPTION AGREEMENT (this "AGREEMENT") is entered into as of
the date set forth on the signature page hereof by and between Clean Energy
Fuels Corp., a Delaware corporation (together with its successors and permitted
assigns, the "COMPANY"), and Boone Pickens Interests, Ltd. (the "INVESTOR").

RECITALS

Subject to the terms and conditions of this Agreement, the Investor
desires to subscribe for and purchase, and the Company desires to issue and sell
to the Investor, certain shares of the Company's common stock, par value $0.0001
per share (the "COMMON STOCK").

AGREEMENT

NOW, THEREFORE, in consideration of the foregoing recitals, which are
incorporated herein by this reference, and for other good and valuable
consideration, the receipt and sufficiency of which are hereby acknowledged, the
parties hereto agree as follows:

1. SUBSCRIPTION AND ISSUANCE OF COMMON STOCK. Subject to the terms and
conditions of this Agreement, the Company will issue and sell to the Investor
and the Investor subscribes for and will purchase from the Company the number of
shares of Common Stock set forth on the signature page hereof (the "SHARES") for
the aggregate purchase price set forth on the signature page hereof, which shall
be equal to the product of the number of Shares subscribed for by the Investor
multiplied by the Purchase Price. The Purchase Price will be equal to the market
closing price on the date of sale as reported in the Wall Street Journal.

2. REPRESENTATIONS AND WARRANTIES OF INVESTOR. The Investor represents
and warrants to the Company that the statements contained in this Section 2 are
truthful and accurate as of the date hereof:

a. This Agreement is a valid and binding obligation of the
Investor, enforceable against the Investor in accordance with its terms. The
Investor is not required to make any filing with, or to obtain any permit,
authorization, consent or approval from, any government or regulatory agency or
any other third party in connection with the execution and delivery of this
Agreement by the Investor, or the performance by the Investor of the
transactions contemplated hereby, other than such filings as may be required
under Section 13 or Section 16 of the Securities Exchange Act of 1934, as
amended (the "Exchange Act"), or any state blue sky laws. There is no action,
suit, claim, proceeding or investigation pending or, to the knowledge of the
Investor, threatened against the Investor which would prevent or hinder the
Investor's performance of any obligations under this Agreement.

b. The Investor is familiar with the business, properties,
operations and condition (financial and otherwise) of the Company, and has such
information which the Investor considers necessary or appropriate to evaluate
the risks and merits of an investment in the Shares.



c. The Investor has such knowledge and experience in
financial, tax and business matters, including substantial experience in
evaluating and investing in common stock and other securities, so as to enable
the Investor to utilize the information described in Section 2(b) to evaluate
the risks and merits of an investment in the Shares and to protect the
Investor's own interests.

d. The Investor is acquiring the Shares for the Investor's own
account only and with no present intention of distributing or selling the Shares
in violation of the Securities Act of 1933, as amended (the "Securities Act"),
and has no arrangement or understanding with any person regarding the
distribution or sale of the Shares in violation of the Securities Act. The
Investor resides or is otherwise located at the address set forth on the
signature page hereof.

e. The Investor understands that the Shares have not been
registered under the Securities Act and are offered and sold to the Investor
pursuant to an exemption from registration under the Securities Act. The
Investor further understands that the certificate representing the Shares will
have the following restrictive legend printed thereon.

THE SHARES REPRESENTED HEREBY HAVE NOT BEEN REGISTERED UNDER THE
SECURITIES ACT OF 1933, AS AMENDED (THE "ACT"), OR UNDER THE SECURITIES
LAWS OF ANY OTHER JURISDICTIONS. THESE SHARES ARE SUBJECT TO
RESTRICTIONS ON TRANSFERABILITY AND RESALE AND MAY NOT BE TRANSFERRED
OR RESOLD EXCEPT AS PERMITTED UNDER THE ACT AND THE APPLICABLE STATE
SECURITIES LAWS, PURSUANT TO REGISTRATION OR EXEMPTION THEREFROM. THE
ISSUER OF THESE SECURITIES MAY REQUIRE AN OPINION OF COUNSEL IN FORM
AND SUBSTANCE SATISFACTORY TO THE ISSUER TO THE EFFECT THAT ANY
PROPOSED TRANSFER OR RESALE IS IN COMPLIANCE WITH THE ACT AND ANY
APPLICABLE STATE SECURITIES LAWS.

f. As indicated above, the Investor's right to transfer the
Shares offered and sold hereby will be restricted. These restrictions will
require the Investor to hold the Shares indefinitely, unless the Shares are
subsequently registered under the Securities Act and qualified or registered
under other applicable state laws, or unless an exemption from such
qualification or registration is available and confirmed by an opinion of
counsel acceptable to the Company. The Investor understands that the Company has
no present intention to register the Shares. After the periods of time described
below, there may, but will not necessarily be, an exemption available under
Section 4(1) of the Securities Act in accordance with SEC Rule 144. Rule 144
allows for limited sales of restricted securities pursuant to Section 4(1) of
the Securities Act after the securities have been held for one year, provided
certain conditions are satisfied, including availability of public information
about the issuer, restrictions on the amount of securities sold within a three
month period, restrictions on the manner of sale, and the filing of a notice
with the SEC. Rule 144 currently provides that the foregoing restrictions do not
apply to a person who has held securities for six months and who has not been an
"affiliate" of the issuer during the three months preceding the sale, other than
the public information requirement. The term "affiliate" is defined in Rule 144
as a person who directly or indirectly controls, is controlled by or is under
common control with the issuer. Executive officers, directors and persons who
directly or indirectly own or control over 5% of the stock of an issuer are
often deemed to be affiliates. The Company is under no obligation to take steps
to ensure the availability of Rule 144, and the Investor should not assume that
the Shares may be resold at any particular time in the future. The holding
period for Rule 144 will commence when the Investor has paid the consideration
for the Shares.

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g. The Investor has not been aware of publication of any
advertisement in connection with the issuance and sale of the Shares.

h. The Investor is an "accredited investor" as such term is
defined in Rule 501(a) of Regulation D promulgated under the Securities Act.

i. The Investor has obtained independent legal and tax advice
concerning this Agreement and the tax consequences thereof to the Investor, or
if not, has expressly waived the Investor's right to do so. The Investor has not
relied on the Company or its representatives for any legal or tax advice.

j. The Investor understands that the Company is under no
obligation to sell the Shares to the Investor unless the Company accepts and
signs this Agreement.

3. REPRESENTATIONS AND WARRANTIES OF THE COMPANY. The Company
represents and warrants to the Investor that the statements contained in this
Section 3 are truthful and accurate as of the date hereof.

a. The execution and delivery of this Agreement by the
Company, and the performance of the Company's obligations hereunder, have been
duly authorized by the board of directors of the Company, including the audit
committee thereof, and no other proceedings on the part of the Company are
necessary to authorize this Agreement and the transactions contemplated hereby.
This Agreement is a valid and binding obligation of the Company, enforceable
against the Company in accordance with its terms.

b. The Company is not required to make any filing with, or to
obtain any permit, authorization, consent or approval from, any government or
regulatory agency or any other third party in connection with the execution and
delivery by the Company of this Agreement and the performance by the Company of
the transactions contemplated hereby (except for such notices and filings as may
be required by the Securities Act or the Exchange Act and any applicable state
securities law after the completion of the transaction). There is no action,
suit, claim, proceeding or investigation pending or, to the knowledge of the
Company, threatened against the Company which would prevent or hinder the
Company's performance of its obligations under this Agreement.

4. SURVIVAL. All representations, warranties, agreements and covenants
made in this Agreement shall survive the execution of this Agreement.

5. FURTHER ASSURANCES. The Investor shall execute such documents and
other papers and take such further actions as may be reasonably required or
desirable to carry out the provisions hereof and the transactions contemplated
hereby.

6. ENTIRE AGREEMENT; MODIFICATION; WAIVER. This Agreement contains the
entire agreement of the parties with respect to the transactions contemplated
hereby, and supersedes all prior agreements, representation and warranties,
written or oral, with respect thereto. This Agreement may be amended only by a
written instrument signed by each of the parties, and the terms hereof may be
waived only by a written instrument signed by each of the parties or, in the
case of a waiver, by the party waiving compliance. All notices given herein
shall be in writing and shall be delivered to the addresses set forth on the
signature page below, or to such other addresses as the Investor or the Company
may designate.

7. NO ASSIGNMENT. Neither this Agreement, nor any of the rights
hereunder, may be assigned by the Investor without the written consent of the
Company.


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8. GOVERNING LAW; DISPUTES. This Agreement shall be governed by and
construed in accordance with the substantive and procedural laws of the State of
California applicable to agreements made and to be performed entirely within
California. The parties hereby agree that any suit, action or other legal
proceeding relating to this Agreement or the transactions contemplated hereby
shall be conducted only in Orange County in the State of California. Each party
hereby irrevocably consents and submits to the exclusive personal jurisdiction
of, and venue in any federal or state court sitting in, such county for any such
proceeding.

9. EXPENSES. Each party shall bear all expenses incurred on behalf of
such party in connection with the preparation, execution and performance of this
Agreement and the transactions contemplated hereby.

10. COUNTERPARTS; EXHIBITS; HEADINGS. This Agreement may be executed in
any number of original or facsimile counterparts, all of which together shall
constitute one and the same instrument. The exhibits attached hereto are
incorporated herein by this reference. The headings herein are for reference
only and shall not affect the interpretation of this Agreement.

11. NOTICE. Notices and other communications to be given to a party
hereunder shall be in writing (including facsimile or other similar electronic
transmission), personally delivered or sent by facsimile or other electronic
transmission, overnight delivery with a nationally recognized delivery service
or by registered or certified mail, return receipt requested, postage prepaid,
to the Investor at the last address furnished to the Company by the Investor in
writing or, in the case of the Company, at the principal offices of the Company,
or at such other address as Investor or the Company may designate by giving
written notice to the other party. Notices or other communications shall be
deemed to be effective upon the earlier of (i) when received by the addressee,
if delivered by hand, facsimile or similar form of electronic transmission, (ii)
one (1) day after sent by facsimile or deposit with a nationally recognized
overnight delivery service and (iii) two (2) days after mailing, if mailed.

12. SEVERABILITY. If any provision of this Agreement or application
thereof is held invalid, the invalidity shall not affect other provisions or
applications of the Agreement (or any of the agreements incorporated by
reference) which can be given effect without the invalid provision or
application.

[SIGNATURE PAGE FOLLOWS]






IN WITNESS WHEREOF, the parties have duly executed and delivered this
Subscription Agreement as of September 24, 2008.

"THE COMPANY"

Clean Energy Fuels Corp.

By:/s/ Rick Wheeler
---------------------------------------
Rick Wheeler, Chief Financial Officer

3020 Old Ranch Parkway, Suite 200
Seal Beach, CA 90740
Fax: 562-546-0097
E-mail address: rwheeler@cleanenergyfuels.com


"INVESTOR"

Name of Investor: BOONE PICKENS INTERESTS, LTD. Address:

By: Robert L. Stillwell 8117 Preston Road #260
------------------- ----------------------

Name: Robert L. Stillwell Dallas TX 75225
------------------------------------ ---------------

Title: MANAGING PARTNER Fax: 217 750 9773
---------------- ------------

E-mail address: ronb@bpcap.net
--------------

By: /s/ Ronald D. Bassett
------------------------------------
Name: Ronald D. Bassett

Title: Managing Partner


Number of Shares subscribed for: 319,488


Aggregate Purchase Price (see Section 1): $4,999,987.20


Exact name to appear on stock certificate: Boone Pickens Interests, Ltd.


[SIGNATURE PAGE TO SUBSCRIPTION AGREEMENT]