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                                                        Exhibit 10.27.4


                      EQUITY COMMITMENT GUARANTY

          This EQUITY COMMITMENT GUARANTY (this "Guaranty" or this
"Agreement"), dated as of December 10, 1997, by NRG ENERGY, INC., a
Delaware corporation ("Guarantor"), in favor of NRG (MORRIS) COGEN, LLC
(the "Borrower") and THE CHASE MANHATTAN BANK, as collateral agent for
the Banks (as defined below) (in such capacity, the "Collateral Agent")
under the Construction and Term Loan Agreement, dated as of September
15, 1997 (the "Credit Agreement"), among the Borrower, the Collateral
Agent, the banks party thereto (the "Banks") and The Chase Manhattan
Bank, as agent for the Banks (in such capacity, the "Agent Bank").

                               RECITALS

A.   As a condition precedent to the Agent Bank, the Collateral Agent
and the Banks entering into the Credit Agreement and the Banks making
the Loans and extending other credit to the Borrower thereunder,
Guarantor executed an Equity Commitment Agreement, dated as of
September 15, 1997 (the "Equity Commitment Agreement"), in favor of the
Borrower and the Collateral Agent.

B.   Pursuant to that certain Membership Interest Purchase Agreement,
dated as of the date hereof, Guarantor is selling all of its membership
interests in the Borrower to NRGG Funding Inc. ("NRGG Funding").

C.   Pursuant to an Assignment and Assumption Agreement, dated as of
the date hereof (the "Assignment and Assumption Agreement"), between
Guarantor and NRGG Funding, NRGG Funding is assuming all of Guarantor's
obligations under the Equity Commitment Agreement.

D.   Guarantor owns 45% of the outstanding shares of capital stock of
NRG Generating and NRG Generating owns 100% of the outstanding shares
of capital stock of NRGG Funding.

E.   It is a condition to the Banks' willingness to continue to make
Loans and extend other credit to the Borrower under the Credit
Agreement that Guarantor enter into this Agreement.

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F.   Guarantor acknowledges that it will obtain substantial benefit if
the Banks continue to make Loans and extend other credit to the
Borrower under the Credit Agreement.

G.   The obligations of Guarantor hereunder are being incurred
concurrently with the assumption by NRGG Funding of Guarantor's
obligations under the Equity Commitment Agreement pursuant to the
Assignment and Assumption Agreement.

H.   Capitalized terms used but not otherwise defined herein shall have
the respective meanings given them in the Equity Commitment Agreement
(including terms incorporated therein from the Credit Agreement).


                               AGREEMENT

     NOW, THEREFORE, in consideration of the premises set forth above
and other good and valuable consideration, receipt of which is hereby
acknowledged, Guarantor hereby agrees as follows:

1.   Guaranty by Guarantor of NRGG Funding Obligation.  Guarantor
unconditionally and irrevocably guarantees payment to the Borrower and
to the Collateral Agent, for the benefit of the Agent Bank and the
Banks, when due of any and all amounts payable by NRGG Funding to the
Borrower from time to time pursuant to Sections 1 and 2 of the Equity
Commitment Agreement and performance in full of all of NRGG Funding's
obligations under Sections 1 and 2 of the Equity Commitment Agreement.

2.   Additional Provisions to Guarantor Obligations.

     (a) In addition to the obligations under Section 1 of this Agreement,
         Guarantor agrees to pay upon demand all fees and expenses incurred by
         the Collateral Agent and the Borrower in successfully enforcing against
         Guarantor any of its obligations and liabilities hereunder or the terms
         hereof, including, without limitation, reasonable fees and expenses of
         legal counsel.  Guarantor waives notice of acceptance of this Agreement
         and of any obligation to which it applies or may apply under the terms
         hereof, and waives diligence, presentment, demand of payment, notice of
         dishonor or non-payment, protest, notice of protest, of any such
         obligations, suit or taking other action by the Collateral Agent or the
         Borrower against, and giving any notice of default or other notice

                                   2

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     to,  or  making any demand on, any party liable thereon (including
Guarantor).

     (b)  Guarantor's obligation under this Agreement is an absolute,
          unconditional, continuing and irrevocable guaranty of payment
          and performance and is in no way conditioned on or contingent
          upon any attempt to enforce in whole or in part NRGG
          Funding's obligations to the Collateral Agent and the
          Borrower under the Equity Commitment Agreement.  If NRGG
          Funding fails to pay or perform any liabilities or
          obligations to the Collateral Agent or the Borrower under
          Section 1 or 2 of the Equity Commitment Agreement as and when
          they are due, Guarantor shall forthwith pay and perform such
          liabilities or obligations, with any such payment to be made
          in immediately available funds.  Each failure by NRGG Funding
          to pay or perform any liabilities or obligations arising
          under Section 1 or 2 of the Equity Commitment Agreement shall
          give rise to a separate cause of action hereunder, and
          separate suits may be brought hereunder as each cause of
          action arises.

     (b)  The Collateral Agent and the Borrower may, at any time and from
          time to time without the consent of or notice to Guarantor, except
          such notice as may be required by applicable Law which cannot be
          waived, without incurring responsibility to Guarantor or impairing
          or releasing the obligations of Guarantor hereunder, upon or without
          any terms or conditions and in whole or in part, (i) exercise or
          refrain from exercising any rights against NRGG Funding or others
          (including Guarantor) or otherwise act or refrain from acting; (ii)
          release any other guarantor from its obligations without obtaining
          the consent of Guarantor and without affecting or impairing the
          obligations of Guarantor hereunder; (iii) settle or compromise any
          obligations hereby guaranteed and/or any obligations incurred
          directly or indirectly in respect thereof or hereof, and may
          subordinate the payment of all or any part thereof to the payment
          of any obligations which may be due to the Collateral Agent, the
          Borrower or others; (iv) sell, exchange, release, surrender,
          realize upon or otherwise deal with in any manner
          or in any order any property by whomsoever pledged or mortgaged to
          secure or howsoever securing the liabilities or obligations hereby
          guaranteed or any liabilities or obligations incurred directly or
          indirectly in respect thereof or hereof and/or any offset there
          against; (v) apply any sums by

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     whomsoever paid or howsoever realized to any obligations  of  NRGG
Funding  to  the  Collateral Agent or the Borrower regardless  of  what
obligations remain unpaid; (vi) consent to or waive any breach  of,  or
any act, omission or default under, the Equity Commitment Agreement  or
otherwise  amend, modify or supplement the Equity Commitment  Agreement
or  any  of such other instruments or agreements; and/or (vii)  act  or
fail  to  act  in  any manner referred to in this Agreement  which  may
deprive Guarantor of its right, if any, to subrogation or reimbursement
against NRGG Funding or any other Person to recover full indemnity  for
any  payments  made  pursuant to this Agreement  or  of  its  right  of
contribution against any other party.

     (d)  No invalidity, irregularity or unenforceability of the
          obligations hereby guaranteed shall affect, impair or be a
          defense to this Agreement.

     (e)  In the event that, notwithstanding the provisions of Section
          2(b) hereof, this Agreement shall be deemed revocable in
          accordance with applicable Law, then any such revocation
          shall become effective only upon actual receipt by the
          Collateral Agent and the Borrower of written notice of
          revocation signed by Guarantor.  No revocation or termination
          hereof shall affect in any manner rights arising under this
          Agreement with respect to obligations and liabilities
          outstanding on the date of receipt by the Collateral Agent
          and the Borrower of written notice of such revocation or
          termination and the sole effect of any revocation and
          termination hereof shall be to exclude from this Agreement
          obligations and liabilities thereafter arising which are
          unconnected with obligations and liabilities theretofore
          arising or transactions theretofore entered into (Guarantor
          shall remain liable for all obligations incurred hereunder
          prior to such revocation or termination).

3.   Representations and Warranties.  Guarantor makes the
representations and warranties set forth below to the Borrower and to
the Collateral Agent, acting for its own benefit and for the benefit of
the other Secured Parties, which representations and warranties shall
survive the execution and delivery of this Agreement:

     (a)  Guarantor is a corporation duly organized, validly existing
          and in good standing under the laws of the State of Delaware
          and has the corporate power and authority to execute and
          deliver this Agreement and to perform its obligations
          hereunder.

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     (b)  Guarantor has taken all necessary corporate action to
          authorize its execution and delivery of this Agreement and
          the performance of its obligations hereunder.

     (c)  This Agreement has been duly executed and delivered by
          Guarantor and constitutes the legal, valid and binding
          obligation of Guarantor, enforceable against Guarantor in
          accordance with its terms, subject to applicable bankruptcy,
          insolvency and other similar Laws affecting creditors' rights
          generally and subject to general equitable principles.

     (d)  All Governmental Approvals and actions necessary in
          connection with the execution and delivery by Guarantor of
          this Agreement and the performance of its obligations
          hereunder have been obtained or performed and remain valid
          and in full force and effect.

     (e)  The execution, delivery and performance of this Agreement, the
          compliance by Guarantor with the provisions hereof and the consumma-
          tion of the transactions contemplated hereby, will not (i) conflict
          with or result in a breach or violation of any of the respective char-
          ters or bylaws of Guarantor or any of its subsidiaries or any material
          franchise or license of Guarantor or any of the terms or provisions
          thereof, (ii) constitute a default or cause an acceleration of any
          obligation under, or result in the imposition or creation of (or the
          obligation to create or impose) any Lien with respect to, any bond,
          note, debenture or other evidence of Indebtedness or any indenture,
          mortgage, deed of trust or other agreement or instrument to which
          Guarantor or any of its subsidiaries is a party or by which it or any
          of them is bound, or to which any properties of Guarantor or any of
          its subsidiaries is or may be subject, (iii) contravene any order of
          any court or Governmental Authority or body having jurisdiction over
          Guarantor or any of its subsidiaries or any of their properties or
          (iv) or conflict with any statute, rule or regulation or administra-
          tive or court decree applicable to Guarantor or any of its subsid-
          iaries or any of their respective properties, in the case of
          clauses (ii), (iii) and (iv) which conflict, breach, violation,
          default or contravention, singly or in the aggregate with each other
          conflict, breach, violation, default or contravention, could
          reasonably be expected to result in a Material Adverse Effect.
          As used in this clause (e) and otherwise in this Agree-

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     ment,  the  term "Material Adverse Effect" shall mean  a  material
adverse  effect  on  either  (A)  the operations,  business,  financial
condition  or  property of Guarantor or any of its  subsidiaries  on  a
consolidated  basis or (B) the ability of Guarantor  to  perform  in  a
timely manner its obligations under this Agreement.

     (f)  There is no legislation, litigation, action, suit, proceeding
          or investigation pending or (to the best of Guarantor's
          knowledge after due inquiry) threatened against Guarantor
          before or by any court, administrative agency, arbitrator or
          Governmental Authority which if adversely determined
          individually or in the aggregate, (i) could reasonably be
          expected to result in a Material Adverse Effect or (ii)
          questions the validity, binding effect or enforceability
          hereof, any action taken or to be taken pursuant hereto or
          any of the transactions contemplated hereby.

     (g)  All quarterly and annual financial statements heretofore
          delivered by or in respect of Guarantor to the Collateral
          Agent, the Agent Bank, the Banks or the Borrower are true,
          correct and complete as of the dates referred to therein, do
          not fail to disclose any material liabilities, whether direct
          or contingent, fairly present the financial condition of
          Guarantor as of the date thereof and are prepared in
          accordance with GAAP.

     (h)  Guarantor possesses all franchises, certificates, licenses,
          permits and other Governmental Approvals necessary for it to
          own its properties, conduct its business and perform its
          obligations under this Agreement.

     (i)  Guarantor is not an "investment company", or a company
          "controlled" by an "investment company", within the meaning
          of the ICA.

     (j)  Guarantor is a "subsidiary company" of a "holding company" as
          those terms are defined in the Public Utility Holding Company
          Act of 1935, as amended ("PUHCA"); however, Guarantor is
          exempt from all provisions of PUHCA by virtue of Section
          3(a)(2) thereof.

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4.   Covenants:  Guarantor agrees that:

     (a)  Guarantor shall maintain in full force and effect all
          consents of any governmental or other authority that are
          required to be obtained by it with respect to this Agreement
          and will obtain any that may become necessary in the future.

     (b)  Guarantor shall comply in all material respects with all
          applicable Laws and orders to which it may be subject if
          failure so to comply would materially impair its ability to
          perform its obligations under this Agreement.

          (i)  Annual Financial Statements.  Guarantor shall deliver to
               the Collateral Agent and the Borrower, within one
               hundred twenty (120) days after the close of each fiscal
               year of Guarantor, the consolidated and consolidating
               balance sheets of Guarantor and its consolidated
               Affiliates as at the end of such fiscal year and the
               related consolidated and consolidating statements of
               income, retained earnings and cash flows for such fiscal
               year, in each case setting forth comparative figures for
               the preceding fiscal year and certified, in the case of
               the consolidated financial statements, by independent
               certified public accountants of recognized national
               standing in the United States.

          (ii) Notice of Default or Litigation.  Promptly, and in any
               event within two (2) Business Days after an Authorized
               Officer of Guarantor obtains knowledge thereof,
               Guarantor shall give to the Collateral Agent and the
               Borrower notice of the occurrence of any event or of any
               litigation or governmental proceeding pending (a)
               against Guarantor or any of its Affiliates which could
               affect the business, operations, property, assets,
               condition (financial or otherwise) or prospects of
               Guarantor so as to materially and adversely affect the
               ability of Guarantor to perform its obligations
               hereunder or (b) with respect to this Agreement, which
               event or pending proceeding is likely to materially and
               adversely affect the business, operations, property,
               assets, condition (financial or otherwise) or prospects
               of Guarantor and its Affiliates taken as a whole.

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          (iii)     Other Information.  From time to time, Guarantor
               shall provide to the Collateral Agent and the Borrower
               such other information or documents (financial or
               otherwise) regarding Guarantor as the Collateral Agent
               or the Borrower may reasonably request and as may be
               available to Guarantor without undue cost or effort.

5.   Subrogation.  Guarantor shall not exercise any rights which it may
acquire by way of subrogation under this Agreement, by any payment made
hereunder or otherwise, until all of the liabilities and obligations of
NRGG Funding to the Collateral Agent and the Borrower under the Equity
Commitment Agreement shall have indefeasibly been paid in full in cash
or cash equivalents.  If any amount shall be paid to Guarantor on
account of such subrogation rights at any time when all such
liabilities and obligations shall not have been indefeasibly paid in
full in cash or cash equivalents, such amount shall be held in trust
for the benefit of the Collateral Agent and the Borrower and shall
forthwith be paid to the Collateral Agent or the Borrower, as
applicable, and applied to such liabilities and obligations, whether
matured or unmatured.

6.   Successions or Assignments.

     (a)  This Agreement shall inure to the benefit of the respective
          successors or assigns of the Collateral Agent and the
          Borrower who shall have, to the extent of their interest, the
          rights of the Collateral Agent and the Borrower hereunder.

     (b)  This Agreement is binding upon Guarantor and its successors
          and assigns.  Guarantor is not entitled to assign its
          obligations hereunder to any other Person without the written
          consent of the Collateral Agent and the Borrower, which may
          be granted or withheld in the Collateral Agent's or the
          Borrower's sole discretion (in the case of the Collateral
          Agent, as directed by the Agent Bank, acting in accordance
          with the Credit Agreement), and any purported assignment in
          violation of this provision shall be void.

7.   Waivers.

     (a)  No delay on the part of the Collateral Agent or the Borrower in
          exercising any of its rights (including those hereunder) and no
          partial or single

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     exercise  thereof  and no action or non-action by  the  Collateral
Agent  or  the Borrower, with or without notice to Guarantor or  anyone
else, shall constitute a waiver of any rights or shall affect or impair
this Agreement.

     (b)  Guarantor agrees that, if the Collateral Agent or the
          Borrower bring any judicial proceedings in relation to any
          such matter, Guarantor will not interpose any counterclaim or
          setoff of any nature.

     (c)  If any amount payable by Guarantor hereunder is not paid as
          and when due, then Guarantor authorizes the Collateral Agent
          and the Borrower to proceed, without prior notice, by right
          of set-off, counterclaim or otherwise, against any assets of
          Guarantor that may at any time be in the possession of the
          Collateral Agent or the Borrower or any branch or office
          thereof, to the full extent of all amounts payable to the
          Collateral Agent and the Borrower hereunder.

     (d)  Guarantor waives any and all notice of the creation, renewal,
          extension or accrual of any of the obligations of NRGG
          Funding under Sections 1 and 2 of the Equity Commitment
          Agreement and notice of or proof of reliance by the
          Collateral Agent or the Borrower upon this Agreement.

     (e)  Guarantor waives diligence, presentment, protest, demand for
          payment and notice of default to or upon NRGG Funding with
          respect to the obligations under Sections 1 and 2 of the
          Equity Commitment Agreement.

8.   Interpretation.  The Section headings in this Agreement are for
the convenience of reference only and shall not affect the meaning or
construction of any provision hereof.

9.   Notices.  All notices in connection with this Agreement shall be
given by notice in writing, hand-delivered or sent by facsimile
transmission, or by certified mail return-receipt requested (airmail,
if overseas), postage prepaid.  All such notices shall be sent to the
appropriate telecopier number or address, as the case may be, set forth
below or to such other number or address as shall have been
subsequently specified by written notice to each other party hereto,
and shall be sent with copies, if any, as indicated below.  All such
notices shall be effective upon receipt.  The addresses for notice
shall be as follows:

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     (a)  The address of Guarantor is:

          NRG ENERGY, INC.
          1221 Nicollet Mall, Suite 700
          Minneapolis, MN 55403-2445
          Attention:  President
          Telephone No.:  (612) 373-5400
          Telecopier No.:  (612) 373-5430

          With a copy to:

          NRG ENERGY, INC.
          1221 Nicollet Mall, Suite 700
          Minneapolis, MN 55403-2445
          Attention:  General Counsel

     (b)  The address of the Collateral Agent is:

          THE CHASE MANHATTAN BANK
          450 West 33rd Street, 15th Floor
          New York, NY 10001
          Attention:     A. Marsula, Assistant Vice President,
International Project                                       Finance,
Global Trust Services
          Telephone No.:  (212) 946-7557
          Telecopier No.:  (212) 946-8177/8178

     (c)  The address of the Borrower is:

          NRG (MORRIS) COGEN, LLC
          1221 Nicollet Mall, Suite 700
          Minneapolis, MN  55403-2445
          Attention:  President
          Telephone No.:  (612) 373-5400
          Telecopier No.:  (612) 373-5430

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          With a copy to:

          NRG (MORRIS) COGEN, LLC
          1221 Nicollet Mall, Suite 700
          Minneapolis, MN  55403-2445
          Attention:  General Counsel

10.  Amendments.  Notwithstanding anything contained herein that may be
construed to the contrary, as between Guarantor, the Collateral Agent
and the Borrower, this Agreement may be amended only with the written
consent of the Collateral Agent, the Borrower and Guarantor, with the
Collateral Agent acting as directed by the Agent Bank (acting upon the
instructions of the Required Banks).

11.  Jurisdiction; Governing Law.

     (a)  Any action or proceeding relating in any way to this
          Agreement may be brought and enforced in the courts of the
          State of New York.  Any such process or summons in connection
          with any such action or proceeding may be served by mailing a
          copy thereof by certified or registered mail, or any
          substantially similar form of mail, addressed to the
          applicable party as provided for notices hereunder.  By
          execution and delivery of this Agreement, Guarantor
          irrevocably agrees to designate, appoint and empower CT
          Corporation System, with its offices as of the date hereof at
          1633 Broadway, New York, New York 10019, to receive for an on
          its behalf service of process in the State of New York and
          further irrevocably consents to the service of process
          outside the territorial jurisdiction of said courts by
          mailing copies thereof in accordance with the immediately
          preceding sentence.  Guarantor represents and warrants that
          it has taken, and will continue to take, all actions
          necessary to retain CT Corporation System as its registered
          agent for service of process in the State of New York for the
          term hereof.

     (b)  This Agreement and the rights and obligations of the parties
          hereto shall be governed by and construed in accordance with
          the Laws of the State of New York without reference to
          principles of conflict of laws (other than Section 5-1401 of
          the New York General Obligations Law).

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12.  Integration of Terms.  This Agreement contains the entire
agreement among the parties hereto relating to the subject matter
hereof and supersedes all oral statements and prior writings with
respect thereto.

13.  Termination; Reinstatement of Guaranty.

     (a)  Subject to the provisions of Section 13(b) hereof, this
          Agreement shall terminate following the payment in full of
          all amounts due hereunder or under Sections 1 and 2 of the
          Equity Commitment Agreement.

     (b)  Notwithstanding the provisions of Section 13(a) hereof, this
          Agreement shall be reinstated if at any time following the
          termination of this Agreement under Section 13(a) hereof, any
          payment or performance by Guarantor under this Agreement or
          NRGG Funding under Section 1 or 2 of the Equity Commitment
          Agreement is rescinded or must otherwise be returned by the
          Collateral Agent, the Borrower or any other Person upon the
          insolvency, bankruptcy, reorganization, dissolution or
          liquidation of NRG Generating or Guarantor and is so
          rescinded or returned to the party or parties making such
          payment or performance, all as though such payment had not
          been made.  Such period of reinstatement shall continue until
          satisfaction of the conditions contained in, and shall
          continue to be subject to, the provisions of this Section 13.

14.  Waiver of Jury Trial.  THE COLLATERAL AGENT (AND THE AGENT BANK
AND THE BANKS AS THIRD PARTY BENEFICIARIES HEREUNDER), THE BORROWER AND
GUARANTOR HEREBY KNOWINGLY, VOLUNTARILY AND INTENTIONALLY WAIVE ANY
RIGHTS THEY MAY HAVE TO A TRIAL BY JURY IN RESPECT OF ANY LITIGATION
BASED HEREON, OR ARISING OUT OF, UNDER OR IN CONNECTION WITH, THIS
AGREEMENT, OR ANY COURSE OF CONDUCT, COURSE OF DEALING, STATEMENTS
(WHETHER VERBAL OR WRITTEN) OR ACTIONS OF THE COLLATERAL AGENT, THE
BORROWER, GUARANTOR OR NRG GENERATING.  THIS PROVISION IS MATERIAL
INDUCEMENT FOR THE COLLATERAL AGENT, THE BORROWER AND GUARANTOR TO
ENTER INTO THIS AGREEMENT.

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<PAGE>

     IN WITNESS WHEREOF, Guarantor has caused this Equity Commitment
Guaranty to be duly executed and delivered as of the day and year first
written above.


                              NRG ENERGY, INC.


                              By:/s/ David H. Peterson
                                   Name: David H. Peterson
                                   Title: President & CEO


Acknowledged and Accepted:

THE CHASE MANHATTAN BANK,
  as Collateral Agent

By: /s/ Annette M. Marsula
      Name: Annette M. Marsula
      Title: Assistant Vice President


NRG (MORRIS) COGEN, LLC

By: /s/ Craig Mataczynski
      Name: Craig Mataczynski
      Title: President