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EXHIBIT 10.5
                             STOCK PLEDGE AGREEMENT


      THIS STOCK PLEDGE AGREEMENT is made as of the 27th day of March, 2002 by
and between Frank W. Getman Jr., an individual residing at 410 Richards Avenue,
Portsmouth, New Hampshire (the "Pledgor"), and BayCorp Holdings, Ltd., a
Delaware corporation, with a principal place of business at 51 Dow Highway, Unit
7, Eliot, Maine (the "Company").

      WHEREAS, the Pledgor is exercising certain incentive stock options and
nonstatutory stock options to acquire shares of the Company's common stock;

      WHEREAS, the Pledgor is exercising 22,066 incentive stock options at an
exercise price of Four Dollars and Ninety Cents ($4.90) per share for a total
number of 22,066 shares of the Company's common stock (the "Shares") at an
aggregate purchase price of One Hundred Eight Thousand, One Hundred Twenty Three
Dollars and Forty Cents ($108,123.40) ("Purchase Price");

      WHEREAS, the Pledgor is borrowing the Purchase Price from the Company
pursuant to the terms of the Pledgor's promissory note dated as of the date
hereof (the "Note");

      WHEREAS, as the sole collateral for the Note, the Pledgor has agreed to
pledge the Shares pursuant to the terms hereof; and

      WHEREAS, the Company shall take possession of the Shares pursuant to the
terms of this Pledge Agreement.

      NOW THEREFORE, in consideration of the covenants and mutual promises set
forth herein, the parties agree as follows:

      1.    PLEDGE. The Pledgor hereby pledges the Shares to secure the payment
of the Note.

      2.    DEPOSIT. The Pledgor hereby deposits with the Company certificates
evidencing the Shares and stock transfer powers for the Shares which are
endorsed in blank (the "Stock Powers"). The Company shall hold such Shares and
Stock Powers subject to the terms of this Pledge Agreement.

      3.    ENCUMBRANCE; HOLDING CERTIFICATES. The Company shall not encumber or
dispose of the Shares except as provided in this Pledge Agreement. The Company
shall keep and preserve the certificates until such time that the Company is
required to deliver the certificates to the Pledgor in accordance with Section
8, 10, or 11, or until such time that the Company is required or allowed to
otherwise dispose of the certificates in accordance with the terms of this
Pledge Agreement.

      4.    DIVIDENDS. During the term of this Pledge Agreement, and so long as
the Pledgor is not in default under the Note, all dividends and other amounts
payable with respect to the

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Shares shall be collectible by the Pledgor for his own use and benefit, unless
otherwise provided herein.

      5.    VOTING. During the term of this Pledge Agreement, and so long as the
Pledgor is not in default under the Note, the Pledgor shall have the right to
vote the Shares on all corporate questions and may exercise all rights and
privileges of ownership thereof, provided, however, the Pledgor shall not
further pledge the equity in the Shares as collateral or otherwise encumber the
Shares in any way.

      6.    SHARE DIVIDENDS. In the event that, during the term of this Pledge
Agreement, any share dividend, reclassification, readjustment, or other change
is declared or made in the capital structure of the Company, all new,
substituted, and additional shares, or other securities, issued by reason of any
such change shall be immediately delivered to and held by the Company under the
terms of this Pledge Agreement in the same manner as the Shares held hereunder.

      7.    WARRANTS. In the event that during the term of this Pledge Agreement
subscription warrants or any other rights or options of any kind shall be issued
in connection with the Shares held hereunder, such warrants, rights and options
shall be immediately assigned by the Pledgor to the Company under this Pledge
Agreement.

      8.    SALE OF SHARES. Notwithstanding any other provision of this Pledge
Agreement, the Pledgor may sell the Shares held pursuant to this Pledge
Agreement during the term hereof so long as the proceeds of such sale are first
applied to pay the outstanding amount due under the Note. Upon notice that the
Pledgor desires to sell the Shares, the Company shall release the certificates
to the Pledgor so that the Pledgor can consummate a sale of the Shares in
accordance with this Section 8. In the event that the sale is not consummated,
the Pledgor shall return the certificates to the Company to be held subject to
the terms of this Pledge Agreement.

      9.    DEFAULT. If the Pledgor is in default under the Note, the Company,
after giving the Pledgor prior written notice, may retain or sell the Shares. If
the Company retains the Shares, it may execute the Stock Powers in its own name.
The Company shall calculate the total value of the retained Shares based on the
then current and readily ascertainable market price and shall remit to the
Pledgor the excess of the total value of the Shares over the amount due under
the Note. Alternatively, the Company shall use commercially reasonable efforts
to sell the Shares. In the event of a sale, the Company may execute the Stock
Powers in favor of the person or entity purchasing the Shares. The Company shall
account to the Pledgor for the proceeds of such sale and shall remit to the
Pledgor the excess of the sale proceeds over the amount due under the Note plus
the reasonable costs of the sale. The decision whether to retain or sell the
Shares shall be made in the Company's sole discretion.

      10.   SATISFACTION OF NOTE. If the Pledgor has not reacquired possession
of the certificates as provided in Section 8 above, upon the Pledgor's
satisfaction of the Note, the Company shall deliver the certificates and Stock
Powers to the Pledgor.


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      11.   PARTIAL SATISFACTION OF NOTE. If the Pledgor pays a portion of the
outstanding principal amount due under the Note, the Pledgor shall be entitled
to receive from the Company a portion of the Shares pledged hereunder. Upon such
partial payment of the Note, the Company shall retain that number of Shares
having an aggregate fair market value equal to two times the Pledgor's remaining
indebtedness, and the Company shall release to the Pledgor a certificate or
certificates evidencing the excess Shares. The Company shall calculate the
number of Shares to be released hereunder and it shall not be obligated to
release fractional Shares. The Shares released to Pledgor in accordance with
this Section 11 shall no longer be subject to the provisions of this Pledge
Agreement.

      12.   DISPUTE. In the event of a dispute between the Pledgor and the
Company as to the disposition of Shares and/or any funds and/or any other rights
held by the Company from time to time acquired in connection with this Pledge
Agreement, or as to the propriety of any acts or refusal to act by the Company
under this Pledge Agreement, the Company may, following the giving of ten (10)
days prior written notice to the Pledgor, in the form and the manner described
for giving notice in this Agreement, deposit in a court of competent
jurisdiction, the certificates, Stock Powers and any funds then held thereunder.

      13.   NOTICES. All notices or communications provided for herein or
incidental to the transactions contemplated hereby shall be in writing and shall
be deemed duly given if delivered personally or sent by certified or registered
mail, return receipt requested, to the parties at the following addresses or
such other addresses as a party may theretofore have specified by notice in
writing as aforesaid:

                  To Pledgor:       Frank W. Getman
                                    410 Richards Avenue
                                    Portsmouth, New Hampshire 03801

                  To the Company:   BayCorp Holdings, Ltd.
                                    51 Dow Highway, Unit 7
                                    Eliot, Maine 03903

      14.   GOVERNING LAW; JURISDICTION. This Pledge Agreement shall be
construed and interpreted according to the laws of the State of New Hampshire.
The parties agree that any suit or action shall only be brought and maintained
in the New Hampshire state courts and the federal courts sitting in New
Hampshire, and the parties hereby consent to such jurisdiction.

      15.   AMENDMENT. This Agreement may only be amended by a writing signed by
both of the parties hereto.

                            [Signature Page Follows]


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      IN WITNESS WHEREOF, the undersigned have placed their hands and seals on
the date first above-written. COMPANY:


                                     BAYCORP HOLDINGS, LTD.


                                     By: /s/ Patrycia T. Barnard
                                        ---------------------------------------
                                        Name:  Patrycia T. Barnard
                                        Title: Treasurer and Vice President of
                                               Finance

                                     PLEDGOR:


                                     /s/ Frank W. Getman Jr.
                                     ------------------------------------------
                                     Frank W. Getman Jr.