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                                                                   EXHIBIT 10.34


                                 PROMISSORY NOTE


$461,501.60                                                        March 7, 2002


         FOR VALUE RECEIVED, John A. Tillinghast, an individual with an address
of 77 Exeter Road, North Hampton, New Hampshire ("Maker"), hereby promises to
pay to the order of BayCorp Holdings, Ltd., a Delaware corporation, with a
principal place of business at 51 Dow Highway, Unit 7, Eliot, Maine ("Holder"),
at the Holder's business address, or at such other place as the Holder or any
subsequent holder hereof may in writing designate the principal sum of Four
Hundred Sixty-One Thousand, Five Hundred One Dollars and Sixty Cents
($461,501.60), with annual interest thereon from the date hereof on the
outstanding principal at the rate of interest stated below. This Note is entered
into in connection with the Maker's exercise of nonstatutory stock options and
is secured by the parties' Stock Pledge Agreement of even date herewith ("Pledge
Agreement").

     1.   TERM. This Note shall mature on the earlier of (i) December 31, 2003
or (ii) thirty (30) days following the payment to Great Bay Power Corporation
("Great Bay"), Little Bay Power Corporation ("Little Bay"), BayCorp Holdings,
Ltd., or its common shareholders, as the case may be, of the proceeds of the
sale of (A) Great Bay's and Little Bay's interests in the Seabrook Nuclear
Generating Station or (B) BayCorp Holdings, Ltd.'s shares of capital stock of
Great Bay and Little Bay or (C) the outstanding shares of capital stock of
BayCorp Holdings, Ltd., by merger, share exchange or otherwise. Upon maturity,
the outstanding principal balance, and all accrued but unpaid interest, and
other expenses, if any, shall be due and payable in full.

     2.   INTEREST RATE. The interest rate on outstanding principal and accrued
but unpaid interest shall be five percent (5%) per annum, which interest shall
be compounded annually and shall accrue.

     3.   NONRECOURSE NOTE. This Note is a nonrecourse note and the Holder's
sole security is and sole recourse shall be against those shares of stock
pledged by the Maker to the Holder or its designee pursuant to the parties'
Pledge Agreement.

     4.   PREPAYMENT. This Note may be prepaid in whole or in part without any
penalty. No prepayment of less than the full unpaid balance of principal and
late charges, if any, shall relieve Maker of the obligation to pay the next
installment of principal hereunder.

     5.   LATE CHARGE. In the event any payments required hereunder are not paid
when due, Maker shall, in addition to all other amounts then due, pay a late
charge (as liquidated damages) equal to five percent (5%) of the overdue
payment(s) of principal and interest. Acceptance by the Holder of payment of the
late charge shall not be deemed a waiver of any default.

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     6.   APPLICATION OF PAYMENTS. All payments by Maker hereunder shall be
applied first to late charges, if any, then to accrued interest and then to
principal due in accordance with the terms hereof.

     7.   EVENTS OF DEFAULT. Upon the occurrence of any of the following events
of default, all sums payable under this Note shall, at the option of the Holder,
become immediately due and payable without further notice or demand:

          7.1  Failure to pay the principal of, or fees or interest on, the
     Note, as the same shall become due and payable, and a continuation of such
     default for ten (10) days after written notice thereof.

          7.2  Default in the due observance or performance of any other
     covenant, condition or agreement, on the part of the Maker to be observed
     or performed pursuant to the terms hereof, or the Pledge Agreement, and a
     continuation of such default for thirty (30) days after notice thereof.

          7.3  The Maker shall (i) apply for or consent to the appointment of a
     receiver, trustee or liquidator of any of his property, (ii) admit in
     writing his inability to pay his debts as they mature, (iii) make a general
     assignment for the benefit of creditors, (iv) be adjudicated a bankrupt or
     insolvent or (v) file a voluntary petition in bankruptcy, or a petition or
     an answer seeking an arrangement with creditors or to take advantage of any
     bankruptcy, insolvency, readjustment of debt, or liquidation law or
     statute, or an answer admitting the material allegations of a petition
     filed against him in any proceeding under any such law.

          7.4  An order, judgment or decree shall be entered, without the
     application, approval or consent of the Maker by any court of competent
     jurisdiction, approving a petition seeking reorganization or approving the
     appointment of a receiver, trustee or liquidator of all or a substantial
     part of his assets, and such order, judgment or decree shall continue
     unstayed and in effect for any period of ninety (90) days.

     8.   WAIVERS. The Maker hereof waives presentment, protest and demand,
notice of protest, demand and dishonor and nonpayment of this Note, and agrees
to pay all costs of collection when incurred, including reasonable attorneys'
fees.

     9.   DELAYS AND OMISSIONS. No delay or omission on the part of the Holder
in exercising any right hereunder shall operate as a waiver of such right, or of
any other right of the Holder, nor shall any delay, omission or waiver on any
one occasion be deemed a bar to or waiver of the same or any other right on any
future occasion. No single or partial exercise of a power hereunder shall
preclude other exercises thereof, or the exercises of any other power hereunder.


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     10.  CHOICE OF LAW. This Note shall be governed exclusively by the laws of
the State of New Hampshire. Maker hereby agrees that any action hereon or
relating hereto may be maintained in a court of competent subject-matter
jurisdiction located in that state, and consents to the jurisdiction of any such
court for all purposes connected herewith.

     11.  ASSIGNMENT; BINDING EFFECT. This Note is not assignable by the Maker.
This Note is binding upon the Maker and his heirs and legal representatives, and
shall inure to the benefit of the Holder, its successors and assigns.

     IN WITNESS WHEREOF, Maker has executed this Note as of the date first
written above.




                                       /s/ John A. Tillinghast
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                                       John A. Tillinghast




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