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[ROBINSON & COLE LETTERHEAD]

                                 March 29, 2000

Securities and Exchange Commission                                   EXHIBIT 5.1
450 Fifth Street N.W.
Washington, D.C.  20549

Re:    FUELCELL ENERGY, INC.
       REGISTRATION STATEMENT ON FORM S-3
       COMMISSION FILE NO. 333-32972

Ladies and Gentlemen:

         We are counsel for FuelCell Energy, Inc. (the "Company") which has
filed a Registration Statement on Form S-3 (the "Registration Statement") for
registration of 1,495,000 shares of common stock of the Company, par value
$.0001 per share ("Common Stock").

         For purposes of this opinion, we have reviewed such questions of law
and examined such corporate records, certificates and other documents as we have
considered necessary or appropriate. We have also examined such certificates of
public officials, corporate documents and records, and other certificates,
opinions and instruments, and have engaged in such other investigation as we
have deemed necessary in connection with the opinion hereinafter set forth. We
have assumed the authenticity of all documents submitted to us as originals, the
genuineness of all signatures, the legal capacity of natural persons, the
conformity to the originals of all documents submitted to us as copies, the
valid execution of all agreements and documents referred to herein by all
parties thereto other than the Company and the enforceability of such agreements
against all parties other than the Company.

         Based on the foregoing we are of the opinion that when up to a maximum
of 1,495,000 shares of Common Stock are issued by the Company pursuant to the
Registration Statement, such shares will, when sold and paid for in accordance
with the Registration Statement, be validly issued, fully paid and
nonassessable.
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Securities and Exchange Commission
March 29, 2000
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         We hereby consent to the use of this opinion as an exhibit to the
Registration Statement and to the reference to our firm under the caption "Legal
Matters" in the Registration Statement and the Prospectus.

                                                    Very truly yours,

                                                    ROBINSON & COLE LLC


                                                    ____________________________
                                                    Richard A. Krantz, a partner

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