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                                                                  Exhibit 10.72

                          ASSET DEMARCATION AGREEMENT

       This Asset Demarcation Agreement (the "Agreement") dated December 15,
1999, by and among The Connecticut Light and Power Company (Seller), a
Connecticut corporation and Connecticut Jet Power LLC, a Delaware limited
liability company ("Connecticut Jet Power"), Devon Power LLC, a Delaware
limited liability company ("Devon Power"), Middletown -Power LLC, a Delaware
limited liability company ("Middletown Power"), Montville Power LLC, a Delaware
limited liability company ("Montville Power"), Norwalk Power LLC, a Delaware
limited liability company ("Norwalk Power"), NRG Devon Operations, Inc., a
Delaware corporation ("Devon Operations"), NRG Middletown Operations, Inc., a
Delaware corporation ("Middletown Operations"), NRG Montville Operations, Inc.,
a Delaware corporation ("Montville Operations"), and NRG Norwalk Harbor
Operations, Inc., a Delaware corporation ("Norwalk Harbor Operations")
(individually the "Buyer" or collectively the "Buyers") and NRG Energy, Inc., a
Delaware Corporation ("NRG"). Capitalized terms used herein and not separately
defined herein shall have the meaning set forth in the Agreement (as defined
below).

                                  WITNESSETH:

       WHEREAS, Seller and NRG have entered into that certain Purchase and Sale
Agreement dated July 1, 1999 (the "Purchase and Sale Agreement"), pursuant to
which Seller has agreed to sell to NRG certain Acquired Assets (the term
"Acquired Assets" and all other capitalized terms not otherwise defined herein
having the respective meanings assigned to them in the Purchase and Sale
Agreement), which constitute all or a portion of Seller's non-nuclear
generation facilities; and

       WHEREAS, pursuant to that certain General Assignment and Assumption
Agreement, dated as of November 30, 1999 (the "Buyers' General Assignment"), a
copy of which is attached hereto as Exhibit 1, NIRG has assigned to the Buyers
and the Buyers have assumed, all of NRG's rights and obligations under the
Purchase and Sale Agreement; and

       WHEREAS, a significant portion of the Acquired Assets, as well as the
T&D Assets and other assets not included in the sale, comprises Improvements
located on real property to be either conveyed to Buyers as part of the sale or
retained by Seller, but the most appropriate point of demarcation between the
portion of the Improvements to be sold to Buyers and the portion to be retained
by Seller does not necessarily correspond to the lot line of the real estate
parcel conveyed or retained, as the case may be; and

       WHEREAS, accordingly, Seller, Buyers and NRG are entering into this
Agreement to evidence their agreement on the demarcation of ownership with
respect to those Improvements not situated wholly on property owned, or to be
owned, by either Seller or Buyers.


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       NOW, THEREFORE, in consideration of the foregoing, Seller, Buyers and
NRG hereby agree as follows:

       1.     Definitions. Whenever used in this Agreement with initial
capitalization, the following terms shall have the meanings specified or
referred to in this section.

       "Buyers Improvement" means that portion of any Improvement owned by the
Buyer, as is specified with respect to each of the Buyers in the Buyers'
General Assignment, after the Closing, specifically including that portion of
any such Improvement located on the property of the Seller, up to the Ownership
Demarcation Point.

       "Improvements" means all buildings, structures (including all fuel
handling and storage facilities), machinery and equipment, fixtures,
construction in progress, including all piping, cables and similar equipment
forming part of the mechanical, electrical, plumbing or HVAC infrastructure of
any building, structure or equipment, located on and affixed to the Sites.

       "Ownership Demarcation Point" means, with respect to any Improvement,
that point where the Seller Improvement ends and the Buyers Improvements
begins. The Ownership Demarcation Point for each Improvement is identified on
Exhibit A and the Schedules attached hereto and is shown on the Plan(s)
identified in such Schedules.

       "Plans" means (a) the surveys, easement or plot plans and sketches, (b)
engineering plans, including electrical, plumbing, heating, ventilating, water
or sewer or drainage system plans, diagrams, schematics, and other pictorial
representations of physical objects, regardless of medium.

       "Seller Improvement" means that portion of any Improvement owned by the
Seller after the Closing, specifically including that portion of any such
Improvement located on the property of the Buyers, up to the Ownership
Demarcation Point.

       2.     Agreement on Demarcation. Buyers, NRG and Seller hereby agree
that the respective Ownership Demarcation Points between the Seller
Improvements and Buyers Improvements shall be as delineated on Exhibit A and
the Schedules and Plans referenced therein. Except to the extent provided
otherwise under Section 3 hereof, Seller shall be responsible for Seller
Improvements up to the Ownership Demarcation Point, and Buyers and NRG shall be
responsible for Buyers Improvements up to the Ownership Demarcation Point.

       3.     Use, Maintenance and Operation of the Improvements. The use,
maintenance and operation of the Buyers Improvements and Seller Improvements,
respectively, to the extent located on the property of the other, shall be
governed by the provisions of the Interconnection Agreement by and between
Seller and Buyers, dated July 1, 1999, as amended, or by the provisions of any
separate Operating Agreement or Service Agreement entered into by the Parties
with respect to such Improvement.

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       4.     Change or Modification of Demarcation. Either Party may at any
time propose to the other Party a change or other modification with respect to
any Ownership Demarcation Point. No such change or modification shall be valid
and binding unless both Parties execute a written amendment to this Agreement,
specifying in detail such change or modification, and attaching a Plan
depicting the new or modified Ownership Demarcation Point.

       5.     Additional Documentation of Transfer. In the event of a change in
the Ownership Demarcation Point, the Parties shall each execute and deliver to
the other such bills of sale or other instruments of transfer, and such other
documentation, as may be necessary under applicable law or regulation, or as
may be reasonably requested by the other Party to effectuate or confirm the
transfer of that portion of the Improvements affected by the modification in
the Ownership Demarcation Point.

       6.     Costs. Unless otherwise agreed by the Parties, all costs and
expenses reasonably attributable to a change or modification of an Ownership
Demarcation Point shall be borne by the Party proposing such change or
modification.

       7.     Regulation. Nothing in this Agreement shall require Buyers or NRG
to own any asset or equipment, operate or maintain any asset or equipment,
provide any service to Seller or to any other person, or take any other action
that could reasonably be expected to result in Buyers or NRG being regulated as
a public utility, electric utility, transmission company, distribution company,
or other entity subject to regulation under the Public Utility Holding Company
Act of 1935, the Federal Power Act (other than with respect to wholesale rates
under Section 205 thereof), or applicable public utility regulation in
Connecticut. The Parties agree to negotiate in good faith to modify this
Agreement to prevent such regulatory impacts from occurring and/or seek waivers
from such regulations, as necessary, and to make such modifications as may be
reasonably necessary to avoid Buyers or NRG becoming regulated as a public
utility solely as a result of this Agreement.

       8.     Representatives. Each Party shall designate an employee to act as
the representative of that Party with respect to issues arising with respect to
Ownership Demarcation Points identified in this Agreement. Any and all issues
with respect to the Ownership Demarcation Points shall in the first instance be
referred to the designated representatives of each Party for review and
decision.

       9.     Notices. All communications under this Agreement shall be in
writing and shall be delivered in person, against receipt, or sent by certified
mail, postage prepaid, return receipt requested, or by overnight delivery by a
courier service providing evidence of receipt, and properly addressed as
follows:

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       If to Seller:

       By mail:      The Connecticut Light and Power Company
                     c/o Northeast Utilities Service Company
                     P.O. Box 270
                     Hartford, CT 06141-0270
                     Attention: John B. Keane
                                Vice President - Generation Divestiture

       By delivery:  The Connecticut Light and Power Company
                     c/o Northeast Utilities Service Company
                     107 Selden Street
                     Berlin, CT 06037
                     Attention: John B. Keane
                                Vice President - Generation Divestiture

       Copy to:      Cheryl Grise, Esquire
                     Vice President, Secretary and General Counsel
                     Northeast Utilities Service Company
                     P.O. Box 270
                     Hartford, CT 06141-0270

       If to Buyers:

                     NRG Energy, Inc.
                     1221 Nicollet Mall, Suite 700
                     Minneapolis, MN 55403-2445
                     Attention:  Vice President and General Counsel
                     FAX:  (612)373-5392

       Copy to:
                     Joseph T. Kinning, Esq.
                     Gray, Plant, Mooty, Mooty & Bennett, P.A.
                     3400 City Center
                     33 South Sixth Street
                     Minneapolis, MN 55402-3796

All notices and other communications required or permitted under this Agreement
shall be effective upon delivery. Any Party may from time to time change its
address for the purpose of notices to that Party by a similar notice specifying
a new address.

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       10.    No Third Party Beneficiaries. Nothing in this Agreement, whether
express or implied, is intended to confer any rights or remedies under or by
reason of this Agreement on any persons other than the Parties and their
respective permitted successors and assigns.

       11.    No Joint Venture. Nothing in this Agreement is intended to create
an association, trust, partnership, or joint venture between the Parties, or
impose a trust, partnership or fiduciary duty, obligation, or liability on or
with respect to either Party.

       12.    Conflicts. In the event of any conflicts or inconsistencies
between the terms of this Agreement and the terms of the Purchase and Sale
Agreement, the terms of this Agreement will control.

       13.    Amendment. No waiver and no modification or amendment of any
provisions of this Agreement shall be effective unless made in writing and duly
signed by the Parties.

       14.    Counterparts.  This Agreement may be executed in one or more
counterparts, each of which is an original, but all of which together
constitute one and the same instrument.

       15.    Governing Law. The validity, interpretation and effect of this
Agreement are governed by and will be construed in accordance with the laws of
the State of Connecticut without regard to its principles of conflicts of law.

       IN WITNESS WHEREOF, Seller, Buyers and NRG have caused this Agreement to
be signed by their respective duly authorized officers, as of the date first
above written.

                                          THE CONNECTICUT LIGHT AND
                                          POWER COMPANY

                                          By:  /s/ John B. Keane
                                              ---------------------------------
                                              John B. Keane
                                              Vice President -
                                              Generation Divestiture

                                          NRG ENERGY, INC.

                                          By:  /s/ Michael J.  Young
                                              ---------------------------------
                                              Michael J.  Young
                                              Attorney in Fact

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                                          CONNECTICUT JET POWER LLC -

                                          By: NRG Connecticut Generating LLC
                                              Its Sole Member

                                              By: /s/ Bryan Riley
                                                  -----------------------------
                                                  Bryan Riley
                                                  Vice President

                                          DEVON POWER LLC

                                          By: NRG Connecticut Generating LLC
                                              Its Sole Member

                                              By: /s/ Bryan Riley
                                                  -----------------------------
                                                  Bryan Riley
                                                  Vice President

                                          MIDDLETOWN POWER LLC

                                          By: NRG Connecticut Generating LLC
                                              Its Sole Member

                                              By: /s/ Bryan Riley
                                                  -----------------------------
                                                  Bryan Riley
                                                  Vice President

                                          MONTVILLE POWER LLC

                                          By: NRG Connecticut Generating LLC
                                              Its Sole Member

                                              By: /s/ Bryan Riley
                                                  -----------------------------
                                                  Bryan Riley
                                                  Vice President

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                                          NORWALK POWER LLC

                                          By: NRG Connecticut Generating LLC
                                              Its Sole Member

                                              By:  /s/ Bryan Riley
                                                  -----------------------------
                                                  Bryan Riley
                                                  Vice President

                                          NRG DEVON OPERATIONS, INC.

                                          By:  /s/ Bryan Riley
                                              ---------------------------------
                                              Bryan Riley
                                              Vice President

                                          NRG MIDDLETOWN OPERATIONS, INC.

                                          By:  /s/ Bryan Riley
                                              ---------------------------------
                                              Bryan Riley
                                              Vice President

                                          NRG MONTVILLE OPERATIONS, INC.

                                          By:  /s/ Bryan Riley
                                              ---------------------------------
                                              Bryan Riley
                                              Vice President

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                                          NRG NORWALK HARBOR
                                          OPERATIONS, INC.

                                          By: /s/ Bryan Riley
                                              ---------------------------------
                                              Bryan Riley
                                              Vice President

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