ADVISORY AGREEMENT
This Advisory Agreement (the "Agreement") is entered into as of the date signed
below by TECOGEN INC., a Delaware corporation ("Tecogen" and, together with its
subsidiaries, the "Company"), and John N. Hatsopoulos (the "Advisor").
1.Service as an Advisor. The Advisor hereby resigns from all officer positions
with the Company effective on June 30, 2018 or the date of the 2018 Annual
Meeting of Shareholders of Tecogen, whichever is sooner. Such action is entirely
voluntary on the part of the Advisor. The Advisor shall remain as an employee of
Tecogen and shall perform such advisory tasks as shall be reasonably requested
by the Board of Directors of Tecogen or its chief executive officer. The Advisor
shall not be required to spend any specific amount of time in his advisory
capacity. It is anticipated that the Advisor’s activities will largely consist
of assisting in Company financings and investor relations. In addition, Advisor
shall be invited to attend all Board of Directors’ meetings. After the effective
date of his resignation, the Advisor will be referred to as “Chairman Emeritus”
of Tecogen as an honorary title. The Advisor shall at all times act in a manner
that he believes will be in the best interests of the Company.
2.    Term. This Agreement may be terminated at any time by either party with or
without cause, provided that the Company may terminate this Agreement only with
the prior approval of the Tecogen Board of Directors. If Tecogen terminates this
Agreement, Tecogen shall continue to make available to the Advisor, at no cost
to the Advisor, all of the employee benefits he was receiving prior to
termination for a period ending at the later of three years from the effective
date of his resignation as an officer of Tecogen or one year after termination
by Tecogen. The provisions of Sections 6 through 9 of this Agreement shall
survive termination. Upon termination by either party, Tecogen shall promptly
pay to the Advisor all accrued compensation and shall reimburse all of his
reimbursable expenses incurred through termination.
3.    Compensation. Until termination of this Agreement, Tecogen shall provide
to Advisor the benefits described on Schedule 1 to this Agreement as his sole
compensation hereunder.
4.    Expenses. The Company agrees to reimburse the Advisor promptly for
reasonable out-of-pocket expenses incurred in connection with the Advisor's
services. It is anticipated that the Advisor will travel on Company business
from time to time, such travel to be in accordance with guidelines specified by
the chief executive officer of Tecogen. Unless otherwise specified in writing by
such chief executive officer, the Advisor shall be entitled to take two trips to
Europe and three to the continental United States per calendar year on Company
business during the term of this Agreement. The Advisor shall retain appropriate
documentation of all business expenses, such as receipts and travel documents,
and submit them to the Company within 90 days of incurring them.
5.    Rights and Obligations of Advisor. Advisor acknowledges and agrees that he
may be considered an “insider” of the Company. The Advisor understands that he
must comply with all applicable securities laws and will continue to be bound by
the Company’s policies on insider trading and its Code of Business Conduct and
Ethics.
6.    Covenants.
6.1    The parties acknowledge that this Agreement has no effect on the
Advisor’s role as a director of American DG Energy, Inc. and Ultera
Technologies, Inc.
6.2    After the effective date of his resignation as an officer of Tecogen, the
Advisor shall have no power or authority to bind the Company or its affiliates
in any respect that is inconsistent with his status of not being an officer of
the Company. The Advisor agrees to take no action that expresses or implies that
the Advisor has such power or authority.
 
7.    Confidential Information; Developments; Mutual Agreements.

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7.1    The Advisor shall keep confidential and not use for his own benefit any
trade secrets or other confidential information of the Company.
7.2    The Company shall own all right, title and interest relating to all
inventions, improvements, discoveries, methods, developments, software, and
works of authorship, whether patentable or not, which are created, made,
conceived or reduced to practice by the Advisor or jointly with others in the
course of the Advisor's performance of services under this Agreement or using
the Company's confidential information or property (collectively,
"Developments"). The Advisor hereby assigns all Developments to Tecogen.
8.    Mutual Releases; Indemnification. The Advisor hereby releases the Company
and its directors and officers from all claims he may have arising from his
service as an officer and director of the Company. The Company hereby releases
the Advisor from all claims it may have arising from the Advisor’s service as an
officer and director of the Company. The Advisor shall continue to be entitled
to all indemnification obligations of the Company, under its charter, bylaws or
other agreements, as if he continued to be an officer and director of the
Company.
9.    Publicity. The Company shall have the right to use the name, biography and
picture of the Advisor on the Company's website, marketing and advertising
materials consistent with past practice.
10.    No Conflicts. The Advisor represents and warrants to the Company that the
Advisor is free to enter into this Agreement and the services to be provided
pursuant to this Agreement are not in conflict with any other contractual or
other obligation to which the Advisor is bound.
11.    Notices. All notices under this Agreement must be given in writing by
first class mail, return receipt requested, recognized overnight delivery
service, or in a .pdf version via receipted email at the addresses indicated in
this Agreement or any other address designated in writing by either party in
accordance with this Section 11.
Notice to Tecogen:
Tecogen, Inc.
45 First Avenue
Waltham, MA 02451
Attention: CEO
Notice to the Advisor: To the address set forth below or to such other
address(es) supplied to the Company by the Advisor from time to time.
12.    Entire Agreement; Amendments; Counterparts. This Agreement constitutes
the entire agreement and understanding of the parties, and supersedes any and
all previous agreements and understandings, whether oral or written, between the
parties with respect to the matters set forth in this Agreement. This Agreement
may be executed and delivered by an email of a scanned signed copy of this
Agreement in any number of counterparts, each of which together shall constitute
one and the same instrument.
IN WITNESS WHEREOF, the parties hereto have executed this Agreement as of the
following date.
Dated: January __, 2018
TECOGEN INC.
By:_____________________
Name: Bonnie Brown
Title: CAO

__________________
John N. Hatsopoulos
Address: _________________________
                 _________________________