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                                                                   Exhibit 10.28


                              EMPLOYMENT AGREEMENT


         THIS EMPLOYMENT AGREEMENT (the "Agreement"), made this 5th day of May,
1998 is entered into by BayCorp Holdings, Ltd., a Delaware corporation with its
principal place of business at 100 Main Street, Suite 201, Dover, New Hampshire
03820 (the "Company"), and John A. Tillinghast, residing at 77 Exeter Road,
North Hampton, New Hampshire 03862 (the "Employee").

                                    RECITALS

         A.       Great Bay Power Corporation, the Company's subsidiary, has
previously employed the Employee pursuant to an Employment Agreement dated
October 8, 1996 (the "Prior Agreement").

         B.       In lieu of the Prior Agreement, the Company desires to employ
the Employee, and the Employee desires to be employed by the Company. In
consideration of the mutual covenants and promises contained herein, and other
good and valuable consideration, the receipt and sufficiency of which are hereby
acknowledged by the parties hereto, the parties agree as follows:

         I.       TERM OF EMPLOYMENT. The Company hereby agrees to employ the
Employee, and the Employee hereby accepts employment with the Company, upon the
terms set forth in this Agreement, for the period commencing on the date hereof
(the "Commencement Date") and ending on May 4, 1999 (such period, as it may be
extended, the "Employment Period"), unless sooner terminated in accordance with
the provisions of Section 4. The term of this Employment Agreement shall
automatically "roll over" for an additional period of one year commencing on 
May 5, 1999 unless either party wishes to terminate this 


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Agreement and then, in that event, either party, at its sole discretion, shall
give notice to the other party no later than February 4, 1999 that this
Agreement shall terminate on May 4, 1999.

         2.       TITLE; CAPACITY. The Employee shall serve as Chairman of the
Board of Directors of the Company (the "Board") and Chief Engineer. The Employee
shall be subject to the supervision of, and shall have such authority as is
delegated to him by, the full Board and the Company's President and Chief
Executive Officer (the "CEO"). The Employee hereby accepts such employment and
agrees to undertake the duties and responsibilities inherent in such positions.
The Employee agrees to devote his time. attention and energies to the business
and interests of the Company during the Employment Period, subject to the
following provisions. The Employee will perform such duties commensurate with
his positions and titles and shall perform said duties as may be assigned to him
by the Board or the CEO for approximately 400 hours per year. The Company may
require that such hours be divided in such a way that the Employee performs at
least 80 hours of services during each three-month period during the Employment
Period. Subject to the foregoing, the Employee will use his best judgment and
his knowledge of the Company's needs in determining the specific days upon which
the agreed upon hours will be performed. The Employee may be required to work in
excess of 400 hours per year only upon mutual consent. The Company acknowledges
and agrees that the Employee shall be permitted to serve as a director of other
corporations and businesses to the extent that such service (i) does not
conflict or interfere in any way with the Employee's obligations and duties
under this Agreement, and (ii) is not for or on behalf of any person or entity
engaged in a business which is directly competitive with the business of the
Company.



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         3.       COMPENSATION.

                  3.1      COMPENSATION. The Company shall pay the Employee, in
monthly installments, compensation of $250 per hour for the Employment Period.
The Employee shall also receive the Company's standard compensation for serving
as a director.

                  3.2      BENEFITS. The Employee shall be entitled (subject to
eligibility) to any employee benefits that the Board has adopted or that may be
adopted during the Employment Period for the benefit of employees of the Company
generally. The Employee shall not be entitled to the benefit of any provisions
of the Company vacation policy.

                  3.3      REIMBURSEMENT OF EXPENSES. The Company shall
reimburse the Employee for all reasonable travel, entertainment and other
expenses incurred or paid by the Employee in connection with, or related to, the
performance of his duties, responsibilities or services under this Agreement,
upon presentation by the Employee of documentation, expense statements, vouchers
and/or such other supporting information as the Company may request; provided,
however, that the amount available for such travel, entertainment and other
expenses may be fixed in advance by the Board.

                  3.4      DIRECTORS' AND OFFICERS' LIABILITY INSURANCE. During
the Employment Period, the Company shall maintain in force and effect, a
directors' and officers' liability insurance policy in form and substance
reasonably satisfactory to the Employee and the Employee's personal legal
counsel.

         4.       EMPLOYMENT TERMINATION. The employment of the Employee by the
Company pursuant to this Agreement shall terminate upon the occurrence of any of
the following:

                  4.1      Expiration of the Employment Period in accordance
with Section 1;

                  4.2      At the election of the Company, for cause,
immediately upon written 


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notice by the Company to the Employee. For the purposes of this Section 4.2,
cause for termination shall be deemed to exist upon (a) a good faith finding by
the Board of failure of the Employee to perform his assigned duties of the
Company, dishonesty, gross negligence or misconduct, or (b) the conviction of
the Employee of, or the entry of a pleading of guilty or nolo contendere by the
Employee to, any crime involving moral turpitude or any felony;

                  4.3      Thirty (30) days after the death or disability of the
Employee. As used in this Agreement, the term "disability" shall mean the
inability of the Employee, due to a physical or mental disability, for a period
of 90 days, whether or not consecutive, during any 360-day period to perform the
services contemplated under this Agreement. A determination of disability shall
be made by a physician satisfactory to both the Employee and the Company,
PROVIDED THAT if the Employee and the Company do not agree on a physician, the
Employee and the Company shall each select a physician and these two together
shall select a third physician, whose determination as to disability shall be
binding on all parties.

         5.       EFFECT OF TERMINATION; SURVIVAL.

                  5.1      EFFECT OF TERMINATION. In the event the Employee's
employment is terminated pursuant to Section 4 above, the Company shall pay to
the Employee the compensation and benefits otherwise payable to him under
Section 3 through the last day of his actual employment by the Company, except
that the option previously granted to the Employee shall be payable as set forth
in the Incentive Stock Option Agreement dated April 24, 1995.

                  5.2      SURVIVAL. The provisions of Sections 6 and 7 shall
survive the termination of this Agreement.

         6.       RESTRICTIONS.

                  (a)      During the Employment Period and for a period of one
(1) year after the


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termination or expiration thereof, the Employee will not directly or indirectly:

                           (i)      recruit, solicit or induce, or attempt to
induce, an employee or employees of the Company to terminate their employment
with, or otherwise cease their relationship with, the Company; or

                          (ii) solicit, divert or take away, or attempt to
divert or to take away, the business or patronage of any of the clients,
customers or accounts, or prospective clients, customers or accounts, of the
Company which were contacted, solicited or served by the Employee while employed
by the Company, or engage in a business directly competitive with the Company's
business, whether as a partner, employee, consultant, or otherwise.

                  (b)      If any restriction set forth in this Section 6 is
found by any court of competent jurisdiction to be unenforceable because it
extends for too long a period of time or over too great a range of activities or
in too broad a geographic area, it shall be interpreted to extend only over the
maximum period of time, range of activities or geographic area as to which it
may be enforceable.

                  (c)      The restrictions contained in this Section 6 are
necessary for the protection of the business and goodwill of the Company and are
considered by the Employee to be reasonable for such purpose. The Employee
agrees that any breach of this Section 6 will cause the Company substantial and
irrevocable damage and therefore, in the event of any such breach, in addition
to such other remedies which may be available, the Company shall have the right
to seek specific performance and injunctive relief.

         7.       PROPRIETARY INFORMATION AND DEVELOPMENTS.

                  7.1      PROPRIETARY INFORMATION.

                           (a)      Employee agrees that all information and
know-how, whether or





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not in writing, of a private, secret or confidential nature concerning the
Company's business or financial affairs (collectively, "Proprietary
Information") is and shall be the exclusive property of the Company. By way of
illustration, but not limitation, Proprietary Information may include projects,
developments, plans, research data, financial data, personnel data, computer
programs, and customer and supplier lists. Employee will not disclose any
Proprietary Information to others outside the Company or use the same for any
unauthorized purposes without written approval by an officer of the Company,
either during or after his employment, unless and until such Proprietary
Information has become public knowledge without fault by the Employee.

                           (b)      Employee agrees that all files, letters,
memoranda, reports, records, data, or other tangible material containing
Proprietary Information, whether created by the Employee or others, which shall
come into his custody or possession, shall be and are the exclusive property of
the Company to be used by the Employee only in the performance of his duties for
the Company.

                           (c)      Employee agrees that his obligation not to
disclose or use information, know-how and records of the types set forth in
paragraphs (a) and (b) above, also extends to such types of information,
know-how, records and tangible property of customers of the Company or suppliers
to the Company or other third parties who may have disclosed or entrusted the
same to the Company or to the Employee in the course of the Company's business.

                  7.2      OTHER AGREEMENT. The Prior Agreement is hereby
terminated from and after the date hereof. Employee hereby represents that he is
not bound by the terms of any agreement with any previous employer or other
party to refrain from using or disclosing any 


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trade secret or confidential or proprietary information in the course of his
employment with the Company or to refrain from competing, directly or
indirectly, with the business of such previous employer or any other party.
Employee further represents that his performance of all the terms of this
Agreement and as an employee of the Company does not and will not breach any
agreement to keep in confidence proprietary information, knowledge or data
required by him in confidence or in trust prior to his employment with the
Company.

         8.       NOTICES. All notices required or permitted under this
Agreement shall be in writing and shall be deemed effective upon personal
delivery or upon deposit in the United States Post Office, by registered or
certified mail, postage prepaid, addressed to the other party at the address
shown above, or at such other address or addresses as either party shall
designate to the other in accordance with this Section 8.

         9.       PRONOUNS. Whenever the context may require, any pronouns used
in this Agreement shall include the corresponding masculine, feminine or neuter
forms, and the singular forms of nouns and pronouns shall include the plural,
and vice versa.

         10.      ENTIRE AGREEMENT. This Agreement constitutes the entire
agreement between the parties and supersedes all prior agreements and
understandings, whether written or oral, relating to the subject matter of this
Agreement.

         11.      AMENDMENT. This Agreement may be amended or modified only by a
written instrument executed by both the Company and the Employee.

         12.      GOVERNING LAW. This Agreement shall be construed, interpreted
and enforced in accordance with the internal laws of the State of New Hampshire.

         13.      SUCCESSORS AND ASSIGNS. This Agreement shall be binding upon
and inure to the benefit of both parties and their respective successors and
assigns, including any corporation 


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with which or into which the Company may be merged or which may succeed to its
assets or business, provided, however, that the obligations of the Employee are
personal and shall not be assigned by him.




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         14.      MISCELLANEOUS.

                  14.1     No delay or omission by the Company in exercising any
right under this Agreement shall operate as a waiver of that or any other right.
A waiver or consent given by the Company on any one occasion shall be effective
only in that instance and shall not be construed as a bar or waiver of any right
on any other occasion.

                  14.2     The captions of the sections of this Agreement are
for convenience of reference only and in no way define, limit or affect the
scope or substance of any section of this Agreement.

                  14.3     In case any provision of this Agreement shall be
invalid, illegal or otherwise unenforceable, the validity, legality and
enforceability of the remaining provisions shall in no way be affected or
impaired thereby.



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         IN WITNESS WHEREOF, the parties hereto have executed this Agreement as
of the day and year set forth above.




                                        BAYCORP HOLDINGS, LTD.


                                        By: /s/ Frank W. Getman Jr.
                                            ----------------------------------- 
                                            Name: Frank W. Getman Jr.
                                            Title: President & CEO




                                        EMPLOYEE


                                            /s/ John A. Tillinghast
                                            ----------------------------------- 
                                            John A. Tillinghast



ACCEPTED AND AGREED TO
  WITH RESPECT TO SECTION 7.2


GREAT BAY POWER CORPORATION


By: /s/ Frank W. Getman Jr.
    -----------------------------------
    Name: Frank W. Getman Jr.
    Title: President