December 3, 1996


Mr. Edward M. Stern
Consolidated Hydro, Inc.
680 Washington Boulevard
Stamford, CT  06901

Curtis Thaxter Stevens Broder & Micoleau LLC
One Canal Plaza
P.O. Box 7320
Portland, ME  04112
Att:  Stephen E. Champagne, Esq.

Dear Sirs:

         This letter will confirm our further agreements in connection with the
Closing of the Merger Agreement (the "Merger Agreement") dated as of July 1,
1996 by and among Consolidated Hydro Maine, Inc. ("CHI Maine"), CHI Universal,
Inc. ("Universal"), Consolidated Hydro, Inc. ("Parent"), Ridgewood Maine Hydro
Corporation (the "General Partner") and Ridgewood Hydro Maine Partners, L.P.
(the "Partnership") and the Option and Escrow Agreement between Universal,
Ridgewood Electric Power Trust IV, a Delaware Business Trust (the "Trust") and
Curtis Thaxter Stevens Broder & Micoleau LLC (the "Escrow Agent") attached to
the Merger Agreement as Exhibit D, in each case as amended by the letter
agreement dated November 15, 1996 (the "Letter Agreement"). Capitalized terms
used herein (unless otherwise indicated) shall have the meanings assigned in the
Merger Agreement.

          1.   The parties to the Merger Agreement hereby agree to amend the
               Merger Agreement as follows:


               a.   The definition of "Current Liabilities" contained in Section
                    1.1 is hereby amended by adding the following phase at the
                    end thereof: "provided, however, that Current Liablilities
                    shall not include the parties of any debt or lease
                    obligations which becomes due after the date the balance
                    sheet is prepared.

               b.   The last paragraph of Section 3.2.4 (as amended), is further
                    amended by deleting the phrase "Six Million Two Hundred
                    Forty-Three Thousand Three Dollars ($6,243,003)" and
                    inserting the phrase "Six Million Three Hundred Four Nine
                    Thousand Four Hundred Forty Seven Dollars ($6,349,447)" in
                    lieu thereof in order to reflect the parties estimate of a
                    December 13, 1996 Closing Date.


          2. Paragraph 6 of the Letter Agreement is amended by deleting the ent
     irety therof and inserting the following in lieu therof: "Contemporaneously
     with the execution of this letter agreement, each of the Trust and Power
     Trust V have made a transfer of immediately available funds to the Escrow
     Agent to be held in escrow hereunder on the following terms:










               a.   The amount transferred by each of the Trust and Power Trust
                    V is Six Million Three Hundred Forty Nine Thousand Four
                    Hundred Forty Seven Dollars ($6,349,447).

               b.   Such funds are to be held by the Escrow Agent and invested
                    in United States Treasury Bills pending the Closing under
                    the Merger Agreement.

               c.   In the event that the Closing under the Merger Agreement
                    shall occur after December 13, 1996, each of the Trust and
                    Power Trust V shall deliver to the Escrow Agent an
                    additional sum of Two Thousand Eight Hundred Ninety Three
                    Dollars ($2,893) for each day after December 13, 1996 that
                    such Closing is delayed.

               d.   Upon the effectiveness of the filing of the Certificate of
                    Merger as described in paragraph 5 above, the Escrow Agent
                    will make the following transfers and deliveries to the
                    addresses specified in Section 10.9 of the Option Agreement:

                    (i)  to Universal, the sum of (x) Six Million Three Hundred
                         Forty-Nine Thousand Four Hundred Forty Seven Dollars
                         ($6,349,447) plus (y) 50% of any amounts received
                         pursuant to Section 6(c) above, which amount represents
                         the payment by the Partnership of the estimated Cash
                         Consideration contemplated by Section 3.2.4 of the
                         Merger Agreement;

                    (ii) to Universal, an additional sum of (x) Six Million
                         Three Hundred Forty-Nine Thousand Four Hundred Forty
                         Seven Dollars ($6,349,447) plus (y) 50% of any amounts
                         received by the Escrow Agent pursuant to Section 6(c)
                         above, which amounts represent the payment by Power
                         Trust V (as assignee of the Trust) of the Trust
                         Exercise Price referred to in Section 1(a) of the
                         Option Agreement;

                    (iii) to each of the Trust and Power Trust V, an amount
                         equal to 50% of the balance of any funds held by the
                         Escrow Agent;

                    (iv) to the Trust, the Trust Deposits (as defined in the
                         Option Agreement);

                    (v)  to Power Trust V, deliver the Universal Deposits (as
                         defined in the Option Agreement); and

                    (vi) to each of the Partnership and Universal, at least one
                         executed copy of the Merger Agreement and the other
                         executed Closing Documents held by the Escrow Agent.










               e.   If the Closing under the Merger Agreement has not occurred
                    by December 31, 1996, then on January 2, 1997 the Escrow
                    Agent shall (i) return all sums transferred to it by the
                    Partnership and Power Trust V pursuant to paragraph 6(a)
                    above (including any interest earned therein) to the Trust,
                    (ii) deliver the Trust Deposits and the Universal Deposits
                    to the Trust and (iii) destroy the executed copies of the
                    Merger Agreement, Certificate of Merger and other Closing
                    Documents held by the Escrow Agent.

               f.   Each of the Partnership, the Trust, Power Trust V, Universal
                    and the Escrow Agent hereby agree that the provisions set
                    forth in Sections 8, 10 and 11 of the Option Agreement shall
                    also apply to the escrow created by this paragraph 6, and
                    such provisions are hereby incorporated by reference in
                    their entirety, except that the notice provision in Section
                    10.9(a) shall be deemed to apply to each of the Partnership,
                    the Trust and Power Trust V.

         3.       Except as amended hereby, the Merger Agreement and
                  the Letter Agreement continue in full force and
                  effect.

         If the foregoing accurately sets forth our agreements, please sign in
the space below.

                                      Sincerely yours,

                                      Ridgewood Maine Hydro Corporation,
                                      for itself and as the
                                      General Partner of
                                      Ridgewood Maine Hydro
                                      Partners, L.P.

                                      By:
                                         -----------------------------
                                         Name:  Robert E. Swanson
                                         Title:  President


                                      Ridgewood Electric Power Trust IV
                                      By: Ridgewood Power Corporation,
                                          Managing Shareholder

                                      By:
                                         -----------------------------
                                         Name:  Robert E. Swanson
                                         Title:  President



                                      Ridgewood Electric Power Trust V
                                      By: Ridgewood Power Corporation,
                                          Managing Shareholder

                                      By:
                                         -----------------------------
                                         Name:  Robert E. Swanson
                                         Title:  President










Accepted and Agreed:
Consolidated Hydro Maine, Inc.
CHI Universal, Inc.
Consolidated Hydro, Inc.

By:_________________________
         Edward M. Stern
         President


Accepted and Agreed:
Curtis Thaxter Stevens Broder & Micoleau LLC
One Canal Plaza
P.O. Box 7320
Portland, ME  04112

By:__________________________
         Name:
         Title: