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                                                                     Exhibit 5.1



                     [Letterhead of Day, Berry & Howard LLP]


                                                                December 6, 2001

Northeast Generation Company
107 Selden Street
Berlin, Connecticut 06027

Re:      Registration Statement on Form S-4
         Northeast Generation Company


Ladies and Gentlemen:

         We have acted as special counsel to Northeast Generation Company, a
Connecticut corporation (the "Company"), in connection with the preparation and
filing of a registration statement on Form S-4 (the "Registration Statement")
relating to the proposed exchange by the Company of (i) $120,000,000 aggregate
principal amount of its 4.998% Series A-1 Senior Secured Bonds due 2005 (the
"Series A-1 Bonds") for $120,000,000 aggregate principal amount of its 4.998%
Series A Senior Secured Bonds due 2005, and (ii) $320,000,000 aggregate
principal amount of its 8.812% Series B-1 Senior Secured Bonds due 2026 (the
"Series B-1 Bonds") for $320,000,000 aggregate principal amount of its 8.812%
Series B Bonds due 2026. The Series A-1 Bonds and the Series B-1 Bonds are
referred to herein as the "Exchange Bonds." The Exchange Bonds will be issued
pursuant to an indenture, dated as of October 18, 2001, between the Company and
The Bank of New York, as trustee, as supplemented by a First Supplemental
Indenture, dated as of October 18, 2001 (as so supplemented, the "Indenture").

         We have made such legal and factual examinations and inquiries,
including an examination of originals or copies certified or otherwise
identified to our satisfaction of such documents, corporate records and
instruments, as we have deemed necessary or appropriate for purposes of this
opinion.

         In our examination, we have assumed the genuineness of all signatures,
the authenticity of all documents submitted to us as originals and the
conformity to authentic original documents of all documents submitted to us as
copies.

         Based on the foregoing, we are of the opinion that, as of the date
hereof, the Exchange Bonds have been duly authorized and, when the Exchange
Bonds have been duly executed, issued, authenticated and delivered in accordance
with the terms of the Indenture and the exchange offer provided for in the
Registration Statement, will have been validly issued and

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delivered, and will constitute valid and binding obligations of the Company,
enforceable against the Company in accordance with their terms, except as may be
limited by bankruptcy, insolvency, reorganization, moratorium or similar laws
relating to or affecting creditors' rights generally, or by general principles
of equity (regardless of whether such enforceability is considered in an action
at law or in equity).

         We express no opinion as to the laws of any jurisdiction other than the
federal laws of the United States of America and the laws of the States of New
York and Connecticut.

         We consent to your filing this opinion as an exhibit to the
Registration Statement and to the reference to our firm contained under the
heading "Legal Matters" in the prospectus contained in the Registration
Statement. In giving such consent, we do not hereby concede that we are within
the category of persons whose consent is required under Section 7 of the
Securities Act of 1933 or the rules and regulations of the Securities and
Exchange Commission thereunder.

                                             Very truly yours,

                                             DAY, BERRY & HOWARD LLP






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