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                                                                   EXHIBIT 4.2.2

EXECUTION COPY

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                         NEW YORK STATE ENERGY RESEARCH
                            AND DEVELOPMENT AUTHORITY


                                       AND


                  CONSOLIDATED EDISON COMPANY OF NEW YORK, INC.


                                   ----------


                   FIRST SUPPLEMENTAL PARTICIPATION AGREEMENT


                           Dated as of October 1, 2002

                                       to

                             PARTICIPATION AGREEMENT

                            Dated as of June 1, 2001


                                   ----------

                                   relating to

               $224,600,000 Facilities Revenue Bonds, Series 2001A
             (Consolidated Edison Company of New York, Inc. Project)


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          THIS FIRST SUPPLEMENTAL PARTICIPATION AGREEMENT, made and dated as of
October 1, 2002 (the "Supplemental Agreement") to the PARTICIPATION AGREEMENT
made and dated as of June 1, 2001, by and between NEW YORK STATE ENERGY RESEARCH
AND DEVELOPMENT AUTHORITY (the "Authority"), a body corporate and politic,
constituting a public benefit corporation, and CONSOLIDATED EDISON COMPANY OF
NEW YORK, INC., a corporation duly organized and existing and qualified to do
business as a public utility under the laws of the State of New York (the
"Company"),

                          W I T N E S S E T H  T H A T:

          WHEREAS, pursuant to special act of the Legislature of the State of
New York (Title 9 of Article 8 of the Public Authorities Law of New York, as
from time to time amended and supplemented, herein called the "Act"), the
Authority has been established as a body corporate and politic, constituting a
public benefit corporation; and

          WHEREAS, pursuant to the Act, the Authority is empowered to contract
with any power company to participate in the construction of facilities to be
used for the furnishing of electric energy to the extent required by the public
interest in development, health, recreation, safety, conservation of natural
resources and aesthetics; and

          WHEREAS, pursuant to the Act, the Authority is also authorized to
extend credit and make loans from bond proceeds to any person for the
construction, acquisition, installation, reconstruction, improvement,
maintenance, equipping, furnishing or leasing of any special energy project (as
defined in the Act) including, but not limited to, facilities for the
distribution of steam or for the reimbursement to any person for costs incurred
in connection with a special energy project completed or not completed at the
time of such credit or loan, which credits or loans may, but need not, be
secured by mortgages, contracts, leases or other instruments, upon such terms
and conditions as the Authority shall determine reasonable in connection with
such credits or loans; and

          WHEREAS, the Authority is also authorized under the Act to borrow
money and issue its negotiable bonds and notes to provide sufficient monies for
achieving its corporate purposes including the refunding of outstanding
obligations of the Authority; and

          WHEREAS, the Authority is also authorized under the Act to enter into
any contracts and to execute all instruments necessary or convenient for the
exercise of its corporate powers and the fulfillment of its corporate purposes;
and

          WHEREAS, the Authority and the Company have entered into the
Participation Agreement, dated as of June 1, 2001 (the "Agreement"), providing
for the refunding of 7 1/2% Electric Facilities Revenue Bonds, Series 1991 A
(Consolidated Edison Company of New York, Inc. Project) and 6 3/4% Facilities
Revenue Bonds, Series 1992 A (Consolidated Edison Company of New York, Inc.
Project) (collectively, the "Prior Bonds") of the Authority which were issued to
finance the acquisition, construction and installation of certain additional
facilities for the furnishing of electric energy within the Company's service
area and as part of such participation,

                                       (1)
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that the Authority issue bonds pursuant to the Act to provide funds to refund
the Prior Bonds; and

          WHEREAS, on June 6, 2001, the Authority issued its Facilities Revenue
Bonds, Series 2001A (Consolidated Edison Company of New York, Inc. Project) in
an aggregate principal amount of $224,600,000 (the "Bonds") under and pursuant
to the Trust Indenture dated as of June 1, 2001 (the "Indenture"), between the
Authority and The Bank of New York, as trustee (the "Trustee"), for the purpose
of paying a portion of the redemption price of the Prior Bonds; and

          WHEREAS, Section 8.04 of the Agreement and Section 14.07 of the
Indenture provide that the Authority and the Company may, in accordance with the
terms thereof, modify, amend or supplement the Agreement; and

          WHEREAS, the Company has requested that the Indenture and the
Agreement be amended to provide that a Liquidity Facility shall not be required
while Bonds bear interest at a Term Rate for a Calculation Period of greater
than 13 months and to clarify certain terms of the Indenture; and

          WHEREAS, simultaneously with the execution and delivery of this
Supplemental Agreement, the Authority and the Trustee have executed and
delivered the First Supplemental Trust Indenture, dated as of October 1, 2002,
to the Indenture (the "Supplemental Indenture"); and

          WHEREAS, all acts, conditions and things necessary or required by the
Constitution and statutes of the State of New York or otherwise, to exist,
happen, and be performed as prerequisites to the execution of this Supplemental
Agreement, do exist, have happened, and have been performed;

          NOW, THEREFORE, for and in consideration of the premises and of the
mutual covenants and agreements hereinafter set forth, the Authority agrees with
the Company, with the written consent of the Trustee, as follows:

                                    ARTICLE I

                           AUTHORIZATION; DEFINITIONS

          Section 1.01. SUPPLEMENTAL AGREEMENT. This Supplemental Agreement is
amendatory and supplemental to the Agreement, and is entered into in accordance
with Section 8.04 of the Agreement and Article XIV of the Indenture; and except
as modified, amended and supplemented by this Supplemental Agreement, the
provisions of the Agreement are in all respects ratified and confirmed and shall
remain in full force and effect.

                                       (2)
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                                   ARTICLE II

                           AMENDMENTS TO THE AGREEMENT

          SECTION 2.01  AMENDMENT TO SECTION 4.09 OF THE AGREEMENT. Section 4.09
is hereby amended to read in its entirety as follows:

     The Company agrees not to request that the interest rate mode applicable to
     the Bonds be adjusted to an Adjustable Rate or a Fixed Rate unless on the
     effective date of the applicable Change in the Interest Rate Mode the Bonds
     shall be rated at least "A" by S&P or "A" by Moody's or "A" by Fitch or an
     equivalent rating by any nationally recognized rating agency. Such rating
     of the Bonds may, but is not required to, be achieved by obtaining a
     Support Facility which meets the requirements of Article VI of the
     Indenture.

     The Company further agrees that it will maintain a Liquidity Facility
     issued by a financial institution rated not less than "A" by at least one
     nationally recognized rating agency in effect with respect to the Bonds at
     all times, except with respect to Bonds bearing an Auction Rate, a Term
     Rate for a Calculation Period of greater than 13 months or a Fixed Rate.

                                   ARTICLE III

                                  MISCELLANEOUS

          Section 3.01. CONSENT TO SUPPLEMENTAL INDENTURE. The Company hereby
consents to the execution and delivery of the Supplemental Indenture.

          Section 3.02. EFFECTIVE DATE; COUNTERPARTS. This Supplemental
Agreement may be simultaneously executed in counterparts. Each such counterpart
so executed shall be deemed to be an original, and all together shall constitute
but one and the same instrument. This Supplemental Agreement shall become
effective upon execution and delivery on October 9, 2002 in accordance with, and
satisfaction of other requirements and conditions of, the Agreement and the
Indenture. Notwithstanding the date of such execution and delivery, for
convenience and purposes of reference this Supplemental Agreement shall be dated
as of October 1, 2002 and may be cited and referred to as the "First
Supplemental Participation Agreement dated as of October 1, 2002".

                   [Signature Page of this Agreement Follows]

                                       (3)
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          IN WITNESS WHEREOF, the parties hereto have caused this Supplemental
Agreement to be duly executed as of the day and year first written above.

                                           NEW YORK STATE ENERGY RESEARCH
                                             AND DEVELOPMENT AUTHORITY



                                           By
                                             -----------------------------------
                                                President

(SEAL)

Attest:



------------------------
  Assistant Secretary

                                           CONSOLIDATED EDISON COMPANY
                                               OF NEW YORK, INC.



                                           By
                                             -----------------------------------
                                                Name:
                                                Title:

(SEAL)

Attest:



------------------------
  Assistant Secretary


            [Signature Page of Supplemental Participation Agreement]

                                       (4)