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                                                                 EXHIBIT 10.2.2

                                  TELERGY, INC.

                              FIRST MODIFICATION TO
                            STOCK PURCHASE AGREEMENT
                                  May 11, 1999
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                                  TELERGY INC.
                 FIRST MODIFICATION TO STOCK PURCHASE AGREEMENT

      This First Modification to Stock Purchase Agreement (this "Agreement") is
entered into as of May 11, 1999, by and among Telergy, Inc., a New York
corporation with offices at One Telergy Parkway, East Syracuse, New York 13057
(the "Company"), and Niagara Mohawk Energy, Inc., ("NME") a Delaware corporation
with offices at 507 Plum Street, Syracuse, New York 13204, and Opinac North
America, Inc. (Opinac) (NME and Opinac are sometimes referred to herein
collectively as the "Purchasers") and, with respect to Sections 5.1 and 5.4
only, Kevin J. Kelly and Brian P. Kelly (the "Founders").

                                    RECITALS

      WHEREAS, NME and the Company entered into a Stock Purchase Agreement dated
November 10, 1999; and

      WHEREAS, Opinac and the Company entered into a Securities Purchase
Agreement dated May 11, 1999; and

      WHEREAS, in connection with their respective investments, the Purchasers
desires to appoint designees to the Company's Board of Directors; and

      WHEREAS, the Company has agreed to appoint NME's designee as further
provided in the Stock Purchase Agreement; and

      WHEREAS, the Company has agreed to appoint Opinac's designee as further
provided herein.

            NOW, THEREFORE, in consideration of the foregoing recitals and the
mutual promises hereinafter set forth, the parties hereto agree as follows:

      1. DESIGNATION TO BOARD OF DIRECTORS

      The Board of Directors shall elect the NME designee to the Board on or
before May 20, 1999, subject to shareholder ratification. As soon as practicable
following the date hereof, the Board of Directors of the Company shall be
composed of and fixed at a minimum of seven members, one whom shall be
designated by NME, and one of whom shall be designated by Opinac. So long as the
Purchasers collectively hold securities representing the right to hold a minimum
of 10% of the outstanding shares of Class A Common stock (or such other number
of shares of Class A Common stock and such other securities into which the Class
A Common Stock may be converted or exchanged as a result of any stock split,
stock dividend, reverse stock split, recombination, reclassification,
recapitalization, reorganization, merger, consolidation or any other similar
action ("Equivalents")), the Founders shall vote or cause to be voted their
shares of the Company's capital stock in favor of the re-election of each of the
Purchasers' designees to the Board, provided that such representation shall be
proportionate to the Purchasers' ownership of Class A Common Stock
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(including Class A Common Stock which the Purchaser has the right to acquire).
In the event Purchasers' ownership of the Class A Common Stock or its Equivalent
falls below 10% but remains equal to or greater than 5% of the outstanding
Common Stock, Purchasers collectively shall be entitled to designate only one
person to the Board of Directors, by written notice to the Company. In the event
Purchasers ownership of Class A Common Stock or its equivalent falls below 5%,
Purchasers shall not be entitled to designate any person to the Board.

      Such designees shall be entitled to access such information of the
Company and its Subsidiaries as shall permit such designees to effectively
function as Directors and shall serve as Directors consistent with the
fiduciary duties imposed at law. Likewise, the Purchasers agree that, so long
as they are the beneficial owner of capital stock of the Company, each shall
vote or cause to be voted all of its shares in favor of the re-election of the
Founders to the Board.

      Notwithstanding anything to the contrary herein, Opinac shall not be
entitled to nominate a person to the Board and the Founders obligation to vote
in favor of the Opinac designee shall become effective only upon conversion of
the Note to the Conversion Shares as provided in the Securities Purchase
Agreement. In the event such conversion has not been completed on or before July
10, 1999, unless the Company is in breach of its obligation to file pursuant to
the Hart-Scott-Rodino Antitrust Improvements Act of 1976, as amended, the
Company's obligations with respect to Opinac's designation of a person to the
Board, as well as Opinac's rights hereunder shall be of no further force and
effect and shall terminate.


1.    Miscellaneous Provisions

      This Agreement shall be governed in all respects by the laws of the State
of New York as such laws are applied to agreements between New York residents
entered into and performed entirely in New York.

      This Agreement constitutes the full and entire understanding and agreement
between the parties with regard to the subjects hereof.

      This Agreement may be amended or modified only upon the written consent of
the Company and each of the Purchasers.

      The obligations of the Company and the rights of the Purchasers under
this Agreement may be waived only with the written consent of the Purchasers.

      All notices required or permitted hereunder shall be in writing and shall
be deemed effectively given for NME and the Company if given in the manner and
method set forth in the Stock Purchase Agreement dated November 10, 1998, and
for Opinac and the Company if given in the manner and method set forth in the
Securities Purchase Agreement dated May 11, 1999.

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      Each of the parties shall pay all costs and expenses that it incurs with
respect to the negotiation, execution, delivery and performance of this
Agreement.

      In the event that any dispute among the parties to this Agreement should
result in litigation, the prevailing party in such dispute shall be entitled to
recover from the losing party all fees, costs and expenses of enforcing any
right of such prevailing party under or with respect to this Agreement,
including without limitation, such reasonable fees and expenses of attorneys and
accountants, which shall include, without limitation, all fees, costs and
expenses of appeals.

      This Agreement may be executed in any number of counterparts, each of
which shall be an original, but all of which together shall constitute one
instrument.

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      IN WITNESS WHEREOF, the parties hereto have executed this Agreement as of
the date set forth in the first paragraph hereof.

                                    COMPANY:

                                    TELERGY, INC.

                                    By: /s/Brian Kelly
                                        --------------------------
                                    Name: Brian Kelly
                                    Title: C.E.O.


                                    PURCHASERS:

                                    OPINAC NORTH AMERICA, INC.

                                    By: /s/Albert J. Budney, Jr.
                                        -------------------------
                                    Name: Albert J. Budney, Jr.
                                    Title: President


                                    NIAGARA MOHAWK ENERGY, INC.

                                    By:  /s/J. Phillip Frazier
                                        --------------------------
                                    Name: J. Phillip Frazier
                                    Title: C.E.O. & President


                                    FOUNDERS:

                                    /s/Kevin J. Kelly
                                    ----------------------------
                                    Kevin J. Kelly, individually

                                    /s/Brian Kelly
                                    ----------------------------
                                    Brian P. Kelly, individually