GS AGRIFUELS PLEDGE AGREEMENT


     PLEDGE AGREEMENT (this  "Agreement"),  dated as of October 25, 2006, by and
between THE  STILLWATER  ASSET-BACKED  FUND LP, a Delaware  limited  partnership
("Lender"), and GS AGRIFUELS CORPORATION, a Delaware corporation ("Pledgor").

     WHEREAS, NextGen Acquisition Inc., a Delaware corporation (the "Borrower"),
and Lender have entered into a credit  agreement dated as of the date hereof (as
amended,  modified  or  supplemented  from time to time in  accordance  with its
terms, the "Credit Agreement");

     WHEREAS,  pursuant to the Credit Agreement, the Lender has agreed to extend
the Term Loan (as defined in the Credit Agreement) to the Borrower, pursuant to,
and subject to the terms and conditions of, the Credit Agreement;

     WHEREAS,  the Pledgor has guaranteed the  obligations of the Borrower under
the Credit  Agreement  pursuant  to a guaranty  dated as of the date hereof (the
"Guaranty"); and

     WHEREAS, by this Pledge Agreement, the Pledgor is providing the Lender with
security for its obligations under the Guaranty.

     NOW, THEREFORE, the parties hereby agree as follows:

1.   Definitions of Terms.  All capitalized  terms used herein,  but not defined
     herein, shall have the meanings set forth in the Credit Agreement.  As used
     herein, the following terms shall have the following meanings:

     (a)  "Collateral" shall have the meaning set forth in Section 2 hereof.

     (b)  "Pledged  Stock"  shall mean all of the shares of common  stock of the
          Borrower owned by the Pledgor.

     (c)  "Proceeds" shall mean any consideration  received from the exchange or
          other  disposition  of any of the Pledged  Stock,  and any other value
          received as a  consequence  of the  possession  of any Pledged  Stock,
          which accrued prior to the occurrence of an Event of Default.

2.   Grant and Perfection of Security Interest.

     (a)  As security  for the payment of the  Obligations,  the Pledgor  hereby
          pledges,  creates and grants to the  Lender,  its  successors  and its
          assigns,  a continuing  security  interest in, lien upon, and right of
          setoff  against,  and hereby assigns to the Lender,  the Pledged Stock
          and Proceeds (the "Collateral").

     (b)  The Pledgor irrevocably and unconditionally  authorizes the Lender (or
          its  agent) to file at any time and from  time to time such  financing
          statements  with  respect to the  Collateral  naming the Lender as the
          secured  party and the Pledgor as debtor,  as the Lender may  require,
          and  including  any other  information  with respect to the Pledgor or
          otherwise required by Article 9 of the Uniform Commercial Code of such
          jurisdiction as the Lender may determine in good faith,  together with
          any  amendment  and   continuations   with  respect   thereto,   which
          authorization shall apply to all financing  statements filed on, prior
          to or after the date hereof.  The Lender hereby  ratifies and approves
          all  financing  statements  naming the Lender as secured party and the
          Pledgor,  as debtor with respect to the Collateral (and any amendments
          with respect to such  financing  statements)  filed by or on behalf of
          the Lender  prior to the date hereof and  ratifies  and  confirms  the
          authorization  of the Lender to file such  financing  statements  (and
          amendments, if any). The Pledgor hereby authorizes the Lender to adopt
          on behalf of the Pledgor any symbol  required for  authenticating  any
          electronic filing.

     (c)  The  certificates  for such  Pledged  Stock,  to the extent  that such
          interests are represented by certificates, accompanied by stock powers
          or other appropriate  instruments of assignment  thereof duly endorsed
          in blank by the Pledgor,  have been  delivered  to the Lender.  If the
          Pledgor at any time receives  additional or  replacement  certificates
          with  respect to the  Collateral,  it shall  immediately  deliver such
          certificates to the Lender.

3.   Representations; Further Assurances.

     (a)  Pledgor is the legal and beneficial  owner of the Pledged Stock,  free
          and clear of all liens,  except such as are  created  pursuant to this
          Agreement.  Pledgor has the legal right to pledge and grant a security
          interest  in the same as herein  provided  without  the consent of any
          other Person other than any such consent that has been obtained.

     (b)  All of the Pledged Stock have been duly  authorized and validly issued
          and is fully paid and non-assessable, and are subject to no options to
          purchase or similar rights of any Person.  Pledgor is not and will not
          become a party to or otherwise be bound by any  agreement,  other than
          this Agreement which restricts in any manner the rights of any present
          or future holder of any of the Pledged Stock with respect thereto.

     (c)  The  Pledgor  will  not  permit  to  be  effected  any   amendment  or
          modification of the charter,  by-laws or other applicable organization
          documents of the Borrower  which would (or would be reasonably  likely
          to) materially  adversely  affect the rights or remedies of the Lender
          hereunder or the value of the Collateral.

     (d)  The Pledgor agrees to take any other actions  reasonably  requested by
          the Lender to insure the attachment, perfection of, and the ability of
          the Lender to enforce,  the security interest of the Lender in any and
          all of the Collateral,  including,  without limitation, (i) executing,
          delivering and, where  appropriate,  filing  financing  statements and
          amendments  relating  thereto under the NYUCC or other applicable law,
          to the  extent,  if any,  that  the  Pledgor's  signature  thereon  is
          required  therefor,  and  (ii)  complying  with any  provision  of any
          statute,  regulation  or  treaty  of  the  United  States  as  to  any
          Collateral  if  compliance  with  such  provision  is a  condition  to
          attachment,  perfection  or  priority  of, or ability of the Lender to
          enforce, the security interest of the Lender in such Collateral.

4.   Taxes;  Encumbrances.  At its  option,  the Lender may  discharge  past due
     taxes,  liens,  security interests or other encumbrances at any time levied
     or  placed  on  the  Collateral,  and  may  pay  for  the  maintenance  and
     preservation  of the  Collateral  to the extent the Pledgor fails to do so,
     and; provided, however, that nothing in this Section 4 shall be interpreted
     as excusing  the Pledgor  from his  performance  of any  covenants or other
     promises  with  respect  to  taxes,  liens,  security  interests  or  other
     encumbrances  and  maintenances  as  set  forth  herein  or in  the  Credit
     Agreement.

5.   Priority.  The Lender's  security  interest in the  Collateral is and shall
     remain a first priority security interest.

6.   Continuing  Obligations of the Pledgor.  The Pledgor shall remain liable to
     observe and perform all the conditions  and  obligations to be observed and
     performed  by it under each  contract,  agreement,  interest or  obligation
     relating to the Collateral, all in accordance with the terms and conditions
     thereof.

7.   Right to Receive Distributions and Vote; Remedies Upon Default.

     (a)  Pledgor  shall be entitled to receive  the  distributions  and profits
          allocable  to the Pledged  Stock and  exercise  the  voting,  consent,
          administration,  management  and other  powers,  rights  and  remedies
          relating  to the Pledged  Stock.  Upon the  occurrence  of an Event of
          Default,  all such powers and rights permitted Pledgor pursuant to the
          preceding sentence shall cease.

     (b)  Upon the occurrence and during the continuance of an Event of Default,
          the Lender  shall have the right,  with or without  legal  process and
          with or without  previous  notice or demand for  performance,  to take
          possession of the Collateral and,  generally,  to exercise any and all
          rights  afforded  to  a  secured  party  under,  and  subject  to  its
          obligations  contained in, the Uniform Commercial Code as in effect in
          any state or other applicable law.

8.   Application of Proceeds. The proceeds of any Collateral shall be applied by
     the Lender as follows:

     FIRST, to the payment of the out-of-pocket costs and expenses of the Lender
and the reasonable fees and expenses of its counsel,  and all expenses  incurred
and advances made by the Lender in connection  with the  administration  of this
Agreement, the Credit Agreement or any other Financing Agreements;

     SECOND, to the payment of the Obligations; and

     THIRD,  to the  Pledgor,  his  successors  and  assigns,  or as a court  of
competent jurisdiction may otherwise direct.

9.   Security Interest Absolute.  All rights of the Lender hereunder,  including
     without  limitation,  the  security  interest  granted  hereunder,  and all
     obligations of the Pledgor  hereunder,  shall be absolute and unconditional
     irrespective  of (i) any lack of validity or  enforceability  of the Credit
     Agreement,  any other  agreement with respect to the Term Loan or any other
     agreement or instrument  relating to any of the foregoing,  (ii) any change
     in the time,  manner or place of  payment  of, or in any other term of, the
     Term Loan, or any other  amendment or waiver of or consent to any departure
     from the Credit Agreement, or any other agreement or instrument,  (iii) any
     exchange,  release or nonperfection of any other Collateral, or any release
     or amendment or waiver of or consent to or  departure  from any  guarantee,
     for the Term Loan,  or (iv) any other  circumstance  which might  otherwise
     constitute a defense available to, or discharge of, the Pledgor, any of the
     Guarantors  or any other  obligor in respect of the Term Loan or in respect
     of this Agreement.

10.  No Waiver.  No failure on the part of the Lender to exercise,  and no delay
     in  exercising,  any right,  power or remedy  hereunder  shall operate as a
     waiver thereof, nor shall any single or partial exercise of any such right,
     power or remedy  by the  Lender  preclude  any  other or  further  exercise
     thereof or the exercise of any other right,  power or remedy.  All remedies
     hereunder  are  cumulative  and are not  exclusive  of any  other  remedies
     provided by law.  The Lender  shall not be deemed to have waived any rights
     hereunder  or under any other  agreement or  instrument  unless such waiver
     shall be in writing and signed by such parties.

11.  Lender Appointed  Attorney-in-Fact.  The Pledgor hereby appoints the Lender
     the  attorney-in-fact of the Pledgor solely for the purpose of carrying out
     the  provisions  of this  Agreement and taking any action and executing any
     instrument  which the Lender may deem  necessary or advisable to accomplish
     the purposes hereof,  which  appointment is irrevocable and coupled with an
     interest.

12.  Submission to Jurisdiction.

     (a)  Any legal action or proceeding  with respect to this  Agreement may be
          brought  in the courts of the State of New York  (located  in New York
          County) or of the United  States of America for the Southern  District
          of New York,  and, by execution  and delivery of this  Agreement,  the
          Pledgor  hereby  accepts  for itself  and in respect of his  property,
          generally  and  unconditionally,  the  jurisdiction  of the  aforesaid
          courts.

     (b)  The Pledgor hereby  irrevocably  waives,  in connection  with any such
          action or proceeding,  any objection,  including,  without limitation,
          any  objection to the laying of venue or based on the grounds of forum
          non conveniens, which she may now or hereafter have to the bringing of
          any such action or proceeding in such respective jurisdictions.

     (c)  The Pledgor hereby  irrevocably  consents to the service of process of
          any of the  aforementioned  courts in any such action or proceeding by
          the mailing of copies thereof by registered or certified mail, postage
          prepaid,  to her,  as the case may be, at her address set forth in the
          Credit Agreement.

     (d)  Nothing  herein shall affect the right of the Lender to serve  process
          in any other manner permitted by law or to commence legal  proceedings
          or otherwise proceed against the Pledgor in any other jurisdiction.

13.  Entire  Agreement;  Waiver of Jury Trial,  etc.

     (a)  This Agreement and the Guaranty constitute the entire contract between
          the parties hereto  relative to the subject matter hereof.  Nothing in
          this Agreement or in the Guaranty,  expressed or implied,  is intended
          to confer upon any party,  other than the parties hereto,  any rights,
          remedies,  obligations  or  liabilities  under  or by  reason  of this
          Agreement or the Guaranty.

     (b)  THE PLEDGOR  HEREBY WAIVES ANY RIGHT IT MAY HAVE TO A TRIAL BY JURY IN
          RESPECT OF ANY LITIGATION DIRECTLY OR INDIRECTLY ARISING OUT OF, UNDER
          OR  IN  CONNECTION   WITH  THIS  AGREEMENT  AND  THE  OTHER  FINANCING
          AGREEMENTS.

     (c)  Except as prohibited by law, each party hereto hereby waives any right
          it may have to claim  or  recover  in any  litigation  referred  to in
          paragraph (b) of this Section 13 any special,  exemplary,  punitive or
          consequential  damages or any damages  other than,  or in addition to,
          actual damages.

     (d)  Each party  hereto (i)  certifies  that no  representative,  Lender or
          attorney of the Lender has represented,  expressly or otherwise,  that
          the Lender would not, in the event of litigation,  seek to enforce the
          foregoing  waivers and (ii)  acknowledges  that it has been induced to
          enter  into this  Agreement  or the  other  Financing  Agreements,  as
          applicable,   by,  among  other   things,   the  mutual   waivers  and
          certifications herein.

14.  Binding Agreement;  Assignments.  This Agreement,  and the terms, covenants
     and  conditions  hereof,  shall be binding upon and inure to the benefit of
     the parties hereto and their respective successors and assigns, except that
     the Pledgor shall not be permitted to assign this Agreement or any interest
     herein or in the Collateral,  or any part thereof,  or any cash or property
     held by the Lender as Collateral under this Agreement.

15.  Applicable  Law. This Agreement  shall be construed in accordance  with and
     governed by the law of the State of New York (other than the  conflicts  of
     laws  principles  thereof)  except  to the  extent  that  the  validity  or
     perfection of the security interest hereunder,  or remedies  hereunder,  in
     respect  of  any  particular  collateral  are  governed  by the  laws  of a
     jurisdiction other than the State of New York.

16.  Notices.  All  communications and notices hereunder shall be in writing and
     given as provided in the Credit Agreement.

17.  Severability.  In the event any one or more of the provisions  contained in
     this  Agreement  should be held invalid,  illegal or  unenforceable  in any
     respect,  the  validity,  legality  and  enforceability  of  the  remaining
     provisions  contained  herein  shall not in any way be affected or impaired
     thereby.

18.  Section Headings. Section headings used herein are for convenience only and
     are not to affect the construction of, or to be taken into consideration in
     interpreting, this Agreement.

19.  Counterparts;  Facsimile  Signatures.  This  Agreement  may be  executed in
     counterparts,  each of which shall  constitute an original but all of which
     when taken  together shall  constitute  but one contract,  and shall become
     effective  when  copies  hereof  which,  when  taken  together,   bear  the
     signatures of each of the parties  hereto shall be delivered to the Lender.
     Delivery of an executed  counterpart  of a signature page to this Agreement
     by  telecopier  shall be  effective  as  delivery  of a  manually  executed
     signature page hereto.

     IN WITNESS  WHEREOF,  the  parties  hereto have duly  executed  this Pledge
Agreement as of the day and year first above written.


                                THE STILLWATER ASSET-BACKED FUND LP


                                By:      /s/
                                Name:
                                Title:


                                GS AGRIFUELS CORPORATION

                                By: /s/ Kevin Kreisler
                                    ------------------------------
                                Name:   Kevin Kreisler
                                Title:  Chairman and Chief Executive Officer