<PAGE>

                                                                   EXHIBIT 10.15

                                      LEASE

                                     Between

                                 SOVEREIGN BANK

                                       and

                             WORLD ENERGY SOLUTIONS

                                 446 Main Street
                               Worcester, MA 01608
<PAGE>

                                      LEASE

     Lease dated September 8, 2004, between SOVEREIGN BANK, A federal savings
bank, having an address 1130 Berkshire Boulevard, Wyomissing, PA 19610
(hereinafter referred to as "Landlord") and WORLD ENERGY SOLUTIONS, a Delaware
corporation having an address at 446 Main Street, Worcester, MA 01608
(hereinafter collectively referred to as "Tenant").

     Landlord and Tenant agree with each other as follows:

ARTICLE 1 - THE PREMISES

     446 Main Street, Worcester, Massachusetts, is referred to as the
"Building". The land and easements appurtenant to the land are described on
Exhibit "A" annexed to this Lease and made a part of it. The land and its
appurtenances and the Building are referred to as the "Property".

     Landlord hereby leases to Tenant, and Tenant hereby hires from Landlord, an
area deemed to be 5,104 rentable square feet (which includes a common area
factor) on the 14th floor of the Building corresponding to the hatched area
depicted on Exhibit "A-1," attached hereto. The premises leased is referred to
as the "Demised Premises" or the "Premises".

ARTICLE 2 - TERM

     This Lease shall be for a term of five (5) years commencing on the
"Commencement Date," which shall be the date which is the first day of the
calendar month after the date on which the "Landlord's Work" required to be done
by Landlord and referenced on Exhibit "D" attached hereto, is "Substantially
Complete" and the Premises are delivered to Tenant, and "Substantially Complete"
shall be evidenced by a certificate of occupancy for the Landlord's Work and a
joint walk-through to develop a punch list. Landlord shall perform, at
Landlord's sole cost and expense, the Landlord's Work described in Exhibit D.
Landlord shall endeavor to have the Landlord's Work completed and the Premises
delivered on or before November 1, 2004. In the event that Landlord has not
Substantially Completed the Premises on or before December 30, 2004 ("Outside
Date"), then Tenant shall have the right to terminate this Lease by written
notice to Landlord at any time after the Outside Date but prior to the date that
Landlord actually Substantially Completes the Premises, and Tenant shall receive
a return of any security deposit paid to Landlord.

     Tenant shall have the right to access the Premises prior to the
Commencement Date, provided that Tenant shall have provided Landlord with a
certificate of insurance in accordance with the terms of this Lease prior to
such access.

     The Expiration Date shall be five years after the Commencement Date. The
period commencing with the Commencement Date and ending with the Expiration Date
is referred to as the "Term". The parties shall, by written confirmation,
establish the Commencement Date and the Expiration Date after delivery of the
Premises to Tenant.


                                       2

<PAGE>

ARTICLE 3 - BASE RENT

     Section 3.1 Base Rent

     Tenant shall pay Landlord as Base Rent for each year during the Term
payable in equal monthly installments on the first day of each month in advance,
without set off or demand:

<TABLE>
<S>            <C>                    <C>
Lease Year 1   $ 76,560.00 annually   $6,380.00 monthly
           2     89,320.00             7,443.33
           3     96,976.00             8,081.33
           4     96,976.00             8,081.33
           5    100,804.00             8,400.33
</TABLE>

     (a) If the Commencement Date is not the first day of a month, the
installment of Base Rent for the initial partial month shall be equitably
prorated and shall be due in advance.

     (b) Tenant shall also pay all sales taxes and all other governmental fees,
charges or taxes on the Base Rent. All payments required under this Lease, other
than Base Rent, shall be deemed "Additional Rent."

ARTICLE 4 - ADDITIONAL RENT - OPERATING EXPENSES AND TAXES

     Section 4.1 Operating Expenses

     (a) Commencing January 1, 2006, Tenant shall pay Landlord as Additional
Rent throughout the Term 2.09% ("Tenant's Share") of the amount by which annual
Total Operating Expenses (as defined below) incurred by Landlord during each
calendar year exceed Total Operating Expenses for calendar Base Year 2005 ("Base
Operating Expenses"). Tenant's Share is equal to the proportion that the
rentable square foot area of the Premises bears to the total usable square foot
office area of the Building, deemed to be 244,072 square feet.

     (b) Tenant's Share of annual Operating Expenses shall be paid in monthly
installments on the first day of each month, in advance, in an amount estimated
by Landlord and subject to adjustment from time to time. Subsequent to the end
of each calendar year, Landlord shall furnish Tenant with a statement of the
actual amount of Tenant's share of Total Operating Expenses for the period. If
the total amount paid by Tenant for any year shall be less than the actual
amount due from Tenant as shown on the statement, Tenant shall pay Landlord the
deficiency within ten (10) days after the furnishing of such statement. If the
total amount paid by Tenant shall exceed the actual amount due from Tenant for
such year, the excess shall be credited against the next installment due from
Tenant under this section, or, if it shall be for the last calendar year of the
term, then, the excess shall be returned with Landlord's statement for such
calendar year.

     Should the Term commence or end on a day other than the first day of a
calendar year, then the Operating Expense charge for the partial year shall be
equitably prorated.

     "Total Operating Expenses" shall mean all expenses paid or incurred by
Landlord or on Landlord's behalf in respect of the repair, maintenance and
operation of the Property and the


                                       3

<PAGE>

curbs, sidewalks and plazas adjoining the same, adjusted as if the Building were
"Fully Occupied" (as hereinafter defined), including, but not limited to:

          (i) salaries, wages, medical, surgical, union and general welfare
benefits (including group life insurance) and pension payments for employees of
Landlord and Landlord's management company engaged in the repair, operation and
maintenance of the Property;

          (ii) payroll taxes, workmen's compensation, uniforms and related
expenses for employees of Landlord and Landlord's management company;

          (iii) the cost of all charges for gas, steam, electricity, any
alternate source of energy, heat, ventilation, air-conditioning, water, sewer
and other utilities furnished to the Property (including the common areas and
leased areas), together with any taxes on the same;

          (iv) the cost of painting and redecorating (other than in leased
areas);

          (v) the cost of all charges for insurance including rent, casualty,
liability and fidelity insurance;

          (vi) the cost and/or rentals of all supplies (including cleaning
supplies), tools, materials and equipment, and sales and other taxes thereon;

          (vii) cost or depreciation of hand tools and other movable equipment;

          (viii) the cost of all charges for window and other cleaning and
janitorial and security services;

          (ix) charges of independent contractors;

          (x) repairs and replacements made by Landlord at its expense, however,
to the extent any replacements are capital, such replacements shall be treated
under subsection (xi) or (xiii) below, as applicable;

          (xi) alterations and improvements to the Property, including any
capital improvements, made by reason of the laws and requirements of any public
authorities or the requirements of insurance bodies and if capital improvements,
amortization over the useful life of the improvement thereon with interest
imputed at the annual rate of ten percent (10%);

          (xii) management fees or, if no managing agent is employed by
Landlord, a sum equal to five percent (5%) of the gross income of the Property;

          (xiii) the cost of any capital improvements to the Property and/or of
any machinery or equipment installed on the Property which has the effect of
reducing the expenses which otherwise would be included in Operating Expenses
amortized over the useful life of the improvements with interest thereon imputed
at the annual rate of ten percent (10%), but such cost allocated to Tenant shall
not be in excess of the actual cost savings to the Operating Expenses;


                                       4

<PAGE>

          (xiv) reasonable legal, accounting and other professional fees
incurred except legal fees incurred in writing leases for other tenants; and

          (xv) all other charges properly allocable to the repair, operation
and/or maintenance of the Property in accordance with generally accepted
accounting principles.

     If following the calendar year in which Base Operating Expenses are
computed the Landlord is not furnishing any particular work or service (the cost
of which if performed by the Landlord, would constitute an Operating Expense) to
any portion of the Property for any reason whatsoever (other than capital
expenditures incurred in the Base Year), then the Operating Expenses for such
period shall be increased by an amount equal to the additional cost which would
have been incurred by Landlord had Landlord furnished such work or service.
Fully Occupied shall mean occupancy of one hundred (100%) percent of the
rentable square footage of office space in the Building.

     Section 4.2 Taxes

     Tenant shall pay Landlord as Additional Rent throughout the Term 2.09%
("Tenant's Share") of the amount by which total Taxes levied for each tax year
exceed Base Taxes. Base Taxes shall mean Taxes payable by Landlord with respect
to the Property for the tax year in which the Commencement Date occurs.

     Landlord shall estimate the tax charge and bill the same to the Tenant on a
monthly basis subject to revision from time to time. If the total amount paid by
Tenant for any tax year shall be less than the actual amount due from Tenant as
shown on such statement, Tenant shall pay Landlord the deficiency within ten
(10) days after the furnishing of such statement. If the total amount paid by
Tenant shall exceed such actual amount due from Tenant the excess shall be
credited against the next installment due from Tenant under this section.

     Should the Term commence or end on a day other than the first day of a tax
year, then the Tax charge for the partial year shall be equitably prorated.

     Taxes, as used herein, shall include present real estate taxes payable on
the Property, any tax substituted in lieu thereof or in addition thereto,
including any tax measured by rental income received by Landlord, but excluding
Federal income taxes.

ARTICLE 5 - USE

     Section 5.1 Use of the Premises

     Tenant shall use and occupy the Premises for general office purposes only
and for no other purpose. Tenant shall abide by and not violate any of the Rules
and Regulations set forth in Exhibit "C", as they may be amended from time to
time.

     Tenant shall comply with all requirements of, and obtain all necessary
permits and licenses required by, laws or governmental authorities and
requirements of insurance carriers to operate its particular business in the
Premises; permits, licenses and requirements applicable to the Building and
Property generally shall be the responsibility of Landlord.


                                       5

<PAGE>

     Tenant shall have access to the Building 24 hours per day, 7 days per week
with the use of a security access card system.

     Section 5.2 Proper Care

     Tenant shall take good care of the Premises and shall not commit waste in
the Premises. Tenant, at its expense, shall promptly make all repairs in and
about the Premises, other than to Building systems or structural elements, which
shall be the responsibility of Landlord.

     Section 5.3 Interference

     Business machines and mechanical equipment belonging to Tenant shall be
placed and maintained, at Tenant's expense, in special settings to eliminate any
noise or vibrations they may cause. In the event Tenant's machines or equipment
cause any interference whatsoever with the normal operation of the Building or
other occupants, they shall be removed from the Premises.

     Section 5.4 Permitted Loads

     The maximum allowable load on any portion of the floor of the Premises is
40 pounds per square foot with an allowance of 20 pounds per square foot for
partitions. No excess load will be allowed except with Landlord's prior written
consent, which consent may be withheld in Landlord's sole discretion. If
Landlord gives consent to a greater load which requires modification to the
Building, Landlord shall perform the same and Tenant shall pay Landlord all
costs for such modifications.

     Section 5.5 Additional Electricity and Cost

     Tenant's use of electricity in the Premises shall not exceed 5 watts per
useable square foot of space in the Demised Premises total connected load,
including lighting, per useable square foot of space in the Demised Premises.
Tenant shall not, without Landlord's prior written consent, connect any
appliance, apparatus or device to the Building's electric system which will in
any way change or alter the capacity of the electric system serving the
Premises. Landlord shall have the right to perform surveys of Tenant's
electrical use and adjust electrical charges to Tenant if Tenant exceeds the use
of 5 watts per useable square foot. Tenant shall pay such charges within ten
(10) days after demand therefore. Should Landlord grant such consent, all
appliances, apparatus or devices required therefore and for the measurement
thereof shall be provided by Landlord and the cost shall be paid by Tenant. As a
condition to granting such consent, Landlord may require Tenant to agree to an
increase in Base Rent to an amount which will reflect the cost of the additional
service to be furnished by Landlord.

     The parties shall execute a supplementary agreement to reflect the
increase, which Agreement shall be effective from the date the additional
service is made available to Tenant. The increase shall be effective whether or
not such supplementary agreement is executed.


                                       6

<PAGE>

ARTICLE 6 - CONDITION OF THE PREMISES AND TENANT IMPROVEMENTS

     Section 6.1 Condition of the Premises

     Tenant accepts the Demised Premises "As Is" as of the Commencement Date,
subject to punch list items remaining as part of Landlord's Work.

     Section 6.2 When Demised Premises Ready for Occupancy

     Landlord shall deliver the Demised Premises to Tenant upon substantial
completion of the Landlord's Work, as described in Article 2.

     Section 6.3 Tenant Plans

     If, at any time after completion of the Landlord's Work, Tenant desires to
make nonstructural improvements to the Premises ("Tenant Improvements"), Tenant,
at Tenant's expense, shall have plans and specifications necessary for the
finishing of the Premises and related improvements prepared by an architect or
engineer licensed to practice in Massachusetts. The plans and specifications
shall be submitted to the Landlord for Landlord's approval, which approval shall
not be unreasonably withheld. Landlord's approval shall not constitute a
representation that the plans meet the requirements of law or governmental
authorities having jurisdiction. Tenant shall pay Landlord's cost to review such
plans within ten (10) days of a demand therefore. Tenant, at Tenant's expense,
shall file all plans. Prior to commencing any construction, Tenant shall obtain
builders risk insurance with a company and in an amount satisfactory to Landlord
and supply Landlord with a certificate of such coverage, naming Landlord as
additional insured. All construction shall be done in accordance with the
approved plans and specifications and Building rules. Within thirty (30) days
following completion of Tenant Improvements, Tenant shall submit to Landlord "as
built" plans of Tenant's Improvements. Tenant shall file all statements required
by the City of Worcester relative to certified costs of any construction
performed in the Demised Premises within thirty (30) days after completion of
such work.

     Section 6.4 Modifications

     Tenant shall not make any structural or other modifications without
obtaining Landlord's prior written consent, which consent may be withheld in
Landlord's sole discretion.

     Section 6.5 Use of Landlord's Services and Equipment

     In the event Tenant, its servants, agents and independent contractors shall
utilize any services of Landlord's personnel or shall utilize any equipment,
machinery or other items which are the property of Landlord, Tenant shall pay
Landlord Landlord's standard charges for such services or equipment and
machinery use on demand.


                                       7

<PAGE>

ARTICLE 7 - SUBORDINATION AND ATTORNMENT

     Section 7.1 Subordination

     At Landlord's election, this Lease shall be subordinate or superior to the
lien of any present or future mortgage ("Superior Mortgage") or master lease
("Superior Lease") irrespective of the time of execution or recording of the
mortgage or master lease. If, from time to time, Landlord shall elect that this
Lease be subordinate to the lien of any mortgage or master lease, Landlord may
exercise the election by giving notice to Tenant but such election shall be
binding upon Tenant only if Tenant receives a commercially reasonable
nondisturbance agreement from the Mortgagee. However, from time to time
thereafter, Landlord may elect that this Lease be paramount to the lien of a
mortgage, and may exercise its election by giving notice to Tenant. The exercise
of any of the elections provided in this Section shall not exhaust Landlord's
right to elect differently thereafter, from time to time. At the election of
Landlord, this clause shall be self-operative and no further instrument shall be
required. Upon Landlord's request, from time to time, Tenant shall:

     (a) confirm in writing and in recordable form that this Lease is
subordinate or paramount (as Landlord may elect) to the lien of any mortgage or
master lease; and/or

     (b) execute an instrument making this Lease subordinate or paramount (as
Landlord may elect) to the lien of any mortgage or master lease, in such form as
may be required by any applicable mortgagee or master lessor.

     Section 7.2 Attornment

     Tenant shall attorn to any transferee, assignee or purchaser of Landlord's
interest in the property and recognize such party as Landlord under this Lease
("Successor Landlord").

     Upon such attornment this Lease shall continue in full force and effect as
a direct lease between Successor Landlord and Tenant upon all of the terms,
conditions and covenants as are set forth in this Lease, except that Successor
Landlord shall not:

     (a) be liable for any previous act or omission of Landlord under this
Lease;

     (b) be subject to any offset not expressly provided for in this Lease which
shall have accrued to Tenant against Landlord; or

     (c) be bound by any previous modification of this Lease or by any previous
prepayment of more than one month's Base Rent, unless such modification or
prepayment shall have been expressly approved in writing by the lessor of the
master lease or the holder of the mortgage.

     Section 7.3 Notice to Mortgagee and Right to Cure

     If any act or omission of Landlord would give Tenant the right to cancel or
terminate this Lease or to claim a partial or total eviction, Tenant shall not
exercise such right until:


                                       8

<PAGE>

     (a) it has given written notice of such act or omission to Landlord and the
holder of any mortgage of the Building ("Superior Mortgagee") and the holder of
any master lease to which this Lease is subject ("Superior Lessor"), whose name
and address shall previously have been furnished to Tenant; and

     (b) until a reasonable period for remedying such act or omission shall have
elapsed following the giving of such notice and following the time when such
Superior Mortgagee or Superior Lessor shall have become entitled to remedy the
same, provided such Superior Mortgagee or Superior Lessor shall with due
diligence give Tenant notice of intention to, and commence and continue to,
remedy such act or omission.

ARTICLE 8 - ASSIGNMENT, SUBLETTING, PLEDGING OR ENCUMBERING OF LEASE

     Section 8.1 Assignment, Subletting, Pledging or Encumbering

     Tenant shall not assign or sublet this Lease in any manner without
Landlord's consent, which consent shall not be unreasonably withheld. In
determining whether to grant such consent, Landlord may consider, inter alia,
(i) the creditworthiness and liquidity of Tenant and the proposed assignee or
subtenant; (ii) the character and business reputation of the proposed assignee
or subtenant; (iii) the use of the Premises by the proposed assignee or
subtenant; (iv) whether its mortgagee(s) has consented to the transaction; and
such other criteria as may be necessary to be reviewed under the circumstances.
In no event shall Tenant pledge or encumber its interest in this Lease.

     Notwithstanding anything to the contrary contained in this Lease, Tenant
may, without Landlord's prior written consent, but upon notice to Landlord,
sublet all of the Premises or assign Tenant's interest in this Lease to: (i) a
subsidiary, affiliate, parent or other entity to Tenant which controls, is
controlled by, or is under common control with, Tenant; (ii) a successor entity
to Tenant resulting from merger, consolidation, non-bankruptcy reorganization,
or government action; or (iii) a purchaser of all or any significant portion of
Tenant's stock or assets. Assignment or subletting of less than all of the
Premises is prohibited.

     Section 8.2 Landlord's Consent

     Any consent by Landlord to assignment, subletting, pledging or encumbering
of Tenant's Lease shall not relieve Tenant of its obligations under the Lease.
As a condition to such consent, Landlord may require that all consideration
received by the transferor in excess of the Base Rent and Additional Rent
payable under this Lease be paid to Landlord. Any consent by Landlord in a
particular instance shall not be deemed to be a waiver of the obligation to
obtain Landlord's approval in the case of any other assignment or subletting.
Any attempted assignment, subletting, pledging or encumbering of Tenant's
interest in this Lease without Landlord's prior written consent shall be null
and void and constitute a default under the Lease.

     Section 8.3 Recapture

     If Tenant wishes to assign this Lease or to sublease all of the Premises,
Tenant shall give Landlord written notice of such intention, which notice shall
include the terms and conditions upon which Tenant proposes to assign or
sublease the Premises. Landlord shall have the right,


                                       9

<PAGE>

exercisable by notice delivered to Tenant within the ten (10) days after
Tenant's notice of intention, to terminate this Lease. If Landlord elects to
terminate this Lease, the termination shall become effective thirty (30) days
after the date the termination notice is forwarded to Tenant. Upon such
termination, all of the liabilities of the parties each to the other shall cease
and terminate except as to covenants of Tenant which survive the termination of
this Lease; provided, however, that Tenant may nullify such termination by
withdrawing, in writing, its notice of intention to assign or sublet by notice
to Landlord given prior to the expiration of the thirty (30) day period.

ARTICLE 9 - INSURANCE

     Section 9.1 Casualty Insurance

     Tenant shall at all times during the Term at its own expense, keep any
improvements installed by Tenant ("Tenant Improvements") and Tenant's Property
insured on an "all risk" basis in an amount equal to not less than one hundred
percent (100%) of the full replacement cost of such Tenant Improvements. In
addition to insurance against loss by fire, windstorm and other perils, Tenant
agrees to provide all other types of insurance as may be reasonably required by
Landlord. All policies shall be carried in companies licensed to do business in
Massachusetts and otherwise reasonably satisfactory to Landlord. Copies of all
policies of insurance or certificates therefor shall be delivered to Landlord
and shall contain a provision that the policy shall not be changed or cancelled
without thirty (30) days' prior written notice to Landlord.

     Section 9.2 Use of Insurance Money to Repair

     In the event of any damage or destruction to the Premises at any time
during the Term, Tenant shall promptly repair or rebuild the Tenant Improvements
in conformity with the requirements of this Lease, including, but not limited
to, Section 6.3, without contribution therefor by Landlord.

     Section 9.3 Liability Insurance

     Tenant shall also obtain and keep in force during the Term, with copies of
policies to be deposited with Landlord, commercial general liability and
property damage insurance in a form acceptable to Landlord and providing
coverage of not less than One Million Dollars ($1,000,000.00) single combined
limit. Landlord reserves the right to require Tenant to increase such coverage
if it becomes customary for tenants of similar buildings located in the City of
Worcester to maintain increased coverage limits. Such policies shall cover
injury or death to persons or damage to property of any person or persons in or
about the Premises and shall be issued by companies acceptable to Landlord. Each
policy shall name Landlord, Landlord's mortgagee, any superior lessor and the
managing agent of the Building as an additional insured and shall contain a
provision that the policy shall not be changed or cancelled without thirty (30)
days' prior written notice to Landlord.

     Section 9.4 Landlord's Right to Make Insurance Payments

     If Tenant shall at any time neglect to maintain any insurance coverage,
Landlord may procure or renew such insurance. Any amount paid for such insurance
by Landlord, including


                                       10

<PAGE>

reasonable expenses, shall be Additional Rent due from Tenant and shall be
payable on the next Rent payment date after such payment.

     Section 9.5 Compliance with Policies

     Tenant shall not violate any condition imposed by any fire insurance,
casualty insurance or liability insurance policy carried by Landlord or Tenant
with respect to the Premises or the Property. If Tenant's use increases the cost
of Landlord's insurance beyond standard rates, Tenant shall pay the increased
cost to Landlord upon demand.

     Section 9.6 Waiver of Subrogation

     Landlord and Tenant shall have no liability to one another, or to any
insurer, by way of subrogation or otherwise, on account of any loss or damage to
their respective property, the Premises or its contents, the Building or the
Property, regardless of whether such loss or damage is caused by the negligence
of Landlord or Tenant, arising out of any of the perils or casualties insured
against by the property insurance policies carried, or required to be carried,
by the parties pursuant to this Lease. The insurance policies obtained by
Landlord and Tenant pursuant to this Lease shall permit waivers of subrogation
which the insurer may otherwise have against the non-insuring party. In the
event the policy or policies do not allow waiver of subrogation prior to loss,
either Landlord or Tenant shall, at the request of the other party, deliver to
the requesting party a waiver of subrogation endorsement in such form and
content as may reasonably be required by the requesting party or its insurer.

ARTICLE 10 - PERSONAL PROPERTY

     Section 10.1 Landlord's Property

     All fixtures, equipment, improvements and appurtenances attached in any way
to the Premises at the Commencement Date or during the Term, whether or not by
Tenant, shall be and remain a part of the Premises and shall be property of
Landlord not to be removed by Tenant, except as expressly provided in Section
10.2.

     Section 10.2 Removal of Property

     By the Expiration Date, Tenant shall remove such fixtures, equipment,
improvements and appurtenances as requested by Landlord which are attached in
any way to the Premises. Tenant shall repair any damage resulting from such
removal.

     Section 10.3 Tenant's Property

     Trade fixtures and office equipment which are placed in the Premises by
Tenant without expense to Landlord, and which can be removed without damage to
the Property or Premises, and all furniture, furnishings and other articles of
movable personal property owned by Tenant ("Tenant's Property"), shall be and
shall remain the property of Tenant and may be removed by Tenant at any time
during the Term provided, however, that the Lease is in good standing at the
time of such removal. Tenant shall repair any damage to the Premises or to the
Property resulting from such removal. Any of Tenant's Property remaining in the
Premises after the


                                       11

<PAGE>

Expiration Date shall be and remain property of Landlord for Landlord to dispose
of as Landlord sees fit, or, at Landlord's option, may be removed and stored at
Tenant's expense.

ARTICLE 11 - HEATING, VENTILATION AND AIR CONDITIONING

     Landlord shall maintain and operate systems which shall supply heating,
ventilation and air conditioning to the Premises. Heating, ventilation and air
conditioning shall be furnished between 8:00 a.m. and 6:00 p.m. on "Business
Days", defined as all days except Saturdays, Sundays, days observed by the
Federal or the State government as legal holidays and union holidays and between
8:00 a.m. and 1:00 p.m. on Saturdays. If Tenant shall require heating,
ventilation or air conditioning service at any other time ("After Hours"),
Landlord shall furnish such service upon reasonable notice from Tenant, and
Tenant shall pay Landlord's then established charges therefore on demand.
Landlord's current After Hours charge is $40 per hour.

ARTICLE 12 - LANDLORD'S SERVICES

     Section 12.1 Elevator Service

     Landlord shall provide elevator service to the floor on which the Premises
are situated between 8:00 a.m. and 6:00 p.m. on Business Days, and between 8:00
a.m. and 1:00 p.m. on Saturdays and an elevator on call shall be available at
all times at no additional charge to Tenant. If Tenant shall require additional
elevator service After Hours such as, additional elevator car service or freight
elevator service during off business hours, Landlord shall furnish such service
upon reasonable notice from Tenant, and Tenant shall pay Landlord's then
established charges therefore on demand.

     Section 12.2 Cleaning Service

     Landlord shall provide janitorial services to the Premises on Business
Days. Janitorial services shall be the services included on Exhibit "B" attached
hereto. Landlord in no event shall be liable for any loss, theft or damage to
the property of Tenant by reason of any activities of Landlord's cleaning
contractors or its employees. Landlord shall not be responsible for the cleaning
of any carpeting in the Premises, other than by vacuum sweeping. If Tenant has
an excessive amount of waste or requires cleaning in addition to that described
on Exhibit B, Tenant shall pay Landlord, as Additional Rent, the cost of removal
and disposal thereof. Tenant shall comply with all recycling programs initiated
by Landlord, imposed by law or the requirements of governmental authorities.

     Section 12.3 Directory Listing

     Landlord, at Tenant's request, shall maintain a listing of Tenant's name in
the Building directory; the size of the name so listed and the location of the
directory shall be within the sole discretion of Landlord. Any change from the
initial listing shall be made at Tenant's expense. Landlord shall provide Tenant
with a building standard identification sign at the entrance to the Demised
Premises.


                                       12

<PAGE>

ARTICLE 13 - ACCESS, ENTRY, CHANGES IN THE BUILDING FACILITIES

     Section 13.1 Access to the Building

     Landlord reserves the right of entry through the Premises to permit access
to any other part of the Property for the purposes of maintenance, decoration or
repair.

     Section 13.2 Ducts

     Tenant shall permit Landlord to install, use and maintain, replace or add
pipes, ducts and conduits within walls, bearing columns and ceilings located in
the Premises.

     Section 13.3 Right of Entry

     Landlord shall have the right to enter the Premises at any time for any
purpose permitted under this Lease, to make any repairs or changes as may be
required by law or due to any emergency affecting the Premises or the Property.
Landlord shall be allowed to take all materials into the Premises that may be
required for such repairs, changes or maintenance without liability to Tenant.
Tenant shall provide Landlord with a key to the Premises and shall not change
its locks without Landlord's prior written consent and without providing to
Landlord a key therefor.

     Section 13.4 Right to Show Premises

     At any time during the Term Landlord may, with reasonable notice to Tenant,
enter the Premises with a prospective tenant, purchaser, mortgagee, investor or
similarly interested party and exhibit the Premises to the party.

     Section 13.5 Changes to Property and Building

     Landlord reserves the right at any time, without incurring any liability to
Tenant, to make changes in or to the Building and the Property, including its
and their integral parts as it may deem necessary or desirable so long as such
changes do not materially affect Tenant's ability to occupy the Premises.

ARTICLE 14 - NOTICE OF ACCIDENTS

     Tenant shall promptly give notice to Landlord, of

          (i)  any accident in or about the Premises,

          (ii) all fires in the Premises,

          (iii) all damages to or defects in the Premises, including the
               fixtures, equipment and appurtenances thereto, and

          (iv) all damage to or defects in any parts of or appurtenances to the
               Building's sanitary, electrical, heating, ventilation, air
               conditioning, elevator and other systems located in or passing
               through the Premises.


                                       13

<PAGE>

ARTICLE 15 - NON-LIABILITY AND INDEMNIFICATION

     Section 15.1 Non-Liability

     Except to extent set forth in Section 15.2, Landlord shall not be liable to
Tenant for any injury or damage to Tenant or to any other person or for any
damage to, or loss of any property of Tenant or of any other person,
irrespective of the cause of such injury, damage or loss, whether or not caused
by or due to the negligent act of the Landlord, its agents, servants or
employees. Tenant's agreement to this clause is part of the consideration for
this Lease.

     Section 15.2 Indemnification

     Tenant hereby indemnifies and holds Landlord harmless from and against any
and all claims, demands, liabilities and expenses, including attorneys' fees
arising from the negligence or wrongful act of Tenant or its agents, employees
or contractors or from any breach by Tenant of the Lease, provided that Tenant's
obligations under this paragraph shall not be effective to the extent such
claims, demands, liabilities or expenses arise out of or relate to the
negligence or wrongful act of Landlord, its agents, employees or contractors and
the breach of this Lease by Landlord. In the event any action or proceeding
shall be brought against Landlord by reason of any such indemnified claim,
Tenant shall defend the same at Tenant's expense by counsel reasonably
satisfactory to Landlord; Landlord expressly agrees that Tenant's insurance
counsel shall be satisfactory. Landlord may participate in any such action or
proceeding through counsel employed at its own expense.

     Landlord hereby indemnifies and holds Tenant harmless from and against any
and all claims, demands, liabilities and expenses, including attorneys' fees,
arising from the negligence or wrongful act of Landlord, its agents, employees
or contractors or from any breach of this Lease by Landlord, provided that
Landlord's obligations under this subparagraph shall not be effective to the
extent such claims, demands, liabilities or expenses arise out of or relate to
the negligence or wrongful act of Tenant, its agents, employees or contractors
or the breach of this Lease by Tenant. In the event any action or proceeding
shall be brought against Tenant by reason of any such indemnified claim,
Landlord shall defend the same at Landlord's expense by counsel reasonably
satisfactory to Tenant; Tenant expressly agrees that Landlord's insurance
counsel shall be satisfactory. Tenant may participate in any such action or
proceeding through counsel employed at its own expense.

     Notwithstanding the foregoing, the parties release each other from any
claims either party ("Injured Party") has against the other. This release is
limited to the extent the claim is covered by the Injured Party's insurance or
the insurance the Injured Party is required to carry under Section 9.3 of the
Lease, whichever is greater.

ARTICLE 16 - DAMAGE OR DESTRUCTION

     Section 16.1 Repair of Damage

     If the Property is damaged or destroyed by fire or other casualty and this
Lease is not terminated in the manner set forth in Section 16.3 hereof, Landlord
shall repair or rebuild the Property at Landlord's expense, but shall not be
required to repair or replace any of Tenant's


                                       14

<PAGE>

Property or any alterations or Tenant Improvements. Landlord shall not be
required to commence repair or restoration until insurance proceeds are
available and shall only be required to rebuild or repair to the extent such
proceeds are sufficient to pay the cost thereof.

     Section 16.2 Rent Abatement

     If the Premises or any portion thereof are rendered untenantable and are
not used as a result of any damage or destruction by fire or other casualty, the
Rent shall abate on that portion of the Premises rendered untenantable and not
used from the date of such damage or destruction to the date of completion of
Landlord's repair of such damage plus thirty (30) days. To the extent Tenant
reoccupies a portion of the Premises, Tenant's abatement shall cease on such
portion on the date of reoccupation.

     Section 16.3 Substantial Destruction

     If the Property is substantially damaged or destroyed by fire or other
casualty, then Landlord may terminate this Lease by giving Tenant notice within
ninety (90) days after the casualty causing the damage. If Landlord exercises
its option to terminate, the Term shall terminate and expire upon the thirtieth
(30th) day after the notice is given and Tenant shall vacate the Premises and
surrender the same to Landlord on or before that date. The Property (whether or
not the Premises are damaged) shall be deemed substantially damaged or destroyed
if the cost of repair and restoration after a casualty occurs is thirty percent
(30%) or more of the then full replacement cost of the Property.

ARTICLE 17 - EMINENT DOMAIN

     Section 17.1 Entire Taking

     If the Building, the Property, or any part of the Premises shall be
lawfully taken for any public or quasi-public purpose, this Lease shall
terminate as of the date of vesting of title in the condemning authority (the
"Date of Taking"), and the Rent and Additional Rent shall be prorated and
adjusted as of that date.

     Section 17.2 Partial Taking

     If any part of the Building or the Property which materially affects
Tenant's use and occupancy of the Premises shall be taken for any public or
quasi-public purpose, then Landlord shall have the option, within thirty (30)
days after the date of taking, to terminate this Lease as of the date of taking.

     Section 17.3 Award

     In the event of any taking, partial or whole, provided for in this Lease,
all of the proceeds of any award, judgment or settlement payable by the
condemning authority shall be the exclusive property of the Landlord. Tenant,
however, may pursue its own claim against the condemning authority permitted
under the laws of the Commonwealth of Massachusetts to be paid to the Tenant so
long as it does not diminish or reduce the award, judgment or settlement
receivable by Landlord.


                                       15

<PAGE>

ARTICLE 18 - SURRENDER

     On the earlier of the Expiration Date, or upon any earlier termination of
this Lease, Tenant shall surrender the Premises to Landlord in the condition it
was in on the Commencement Date, reasonable wear and tear excepted, and broom
swept. Landlord may require Tenant to remove any alterations made by Tenant to
the Premises at Tenant's expense, provided Landlord must exercise such
requirement at the time of approval of the applicable alteration.

ARTICLE 19 - DEFAULT

     Section 19.1 Event of Default

     Each of the following shall be an Event of Default under this Lease:

     (a) If Tenant shall commit an act of bankruptcy, receivership, insolvency,
reorganization, dissolution, liquidation or if other similar proceedings shall
be instituted by Tenant under the Federal Bankruptcy Act or other law of the
United States or other jurisdiction; or if any act of bankruptcy, receivership,
insolvency, reorganization, dissolution, liquidation or other similar
proceedings shall be instituted against Tenant under the Federal Bankruptcy Act
or other similar law of the United States or any other jurisdiction or there is
a material adverse change in Tenant's financial condition.

     (b) If Tenant does not pay the Base Rent or Additional Rent when due.

     (c) If Tenant fails to perform any of the other terms of this Lease, and
such failure shall continue for thirty (30) days following notice of such
failure, plus, if such default cannot reasonably be cured within such 30-day
period, and Tenant shall not commence such cure within said 30-day period, such
time as is reasonably necessary to effectuate the cure, as long as Tenant is
diligently prosecuting to completion of such cure.

     Section 19.2 Landlord's Remedies for Event of Default

     Following an Event of a Default by Tenant, Landlord shall be entitled to
take such action as it deems advisable, including any one or more of the
following:

     (a) Landlord may proceed, at law or in equity, to enforce the provisions of
this Lease.

     (b) Landlord may reenter the Premises, with or without termination of this
Lease and may repossess the Premises. The re-entry and/or repossession may be
effected by summary proceedings, ejectment or otherwise. Landlord may dispossess
Tenant and may remove Tenant from the Premises without notice. Tenant waives any
right to re-enter the Premises or to the service of any notice of Landlord's
intention to re-enter the Premises as may be provided for by any present or
future law. No such re-entry or taking possession of the Premises by Landlord
shall be construed as an election to terminate this Lease unless a written
notice of termination is given to Tenant. Notwithstanding any re-entry without
termination, Landlord may at any time elect to terminate this Lease.


                                       16

<PAGE>

     (c) Landlord may notify Tenant that this Lease shall terminate on a
specified date and that this Lease, including Tenant's rights hereunder, shall
terminate on the date so specified. Should Landlord terminate this Lease,
Landlord may, in addition to any other remedies, recover from Tenant all damages
incurred by reason of Tenant's breach, including the cost of recovering the
Premises, attorneys' fees and the amount of Base Rent and Additional Rent
reserved in this Lease for the remainder of the Term over the then reasonable
rental value of the Premises for the remainder of the Term, which sum shall be
immediately due and payable from Tenant to Landlord.

     (d) Landlord may relet the Premises, without termination of Tenant's Lease,
in whole or in part, for a term that may be as long as Landlord may specify. A
lease executed by Landlord in accordance with this subsection may provide for
extensions or renewals of the term. The term of any lease and the period by
which the term may be extended may be greater or less than the period which
would have constituted the balance of the Term had Tenant not defaulted.
Landlord shall be under no duty, however, to relet the Premises or to collect
any rent in connection with a reletting.

     (e) Should Landlord elect to relet the Premises, such rental or rentals
shall be upon such terms and conditions as Landlord may deem advisable. Upon
such reletting, all rentals received by the Landlord shall be applied first, to
the payment of any indebtedness other than Base Rent or Additional Rent due
hereunder from Tenant to Landlord including the cost of reletting, brokerage
fees, attorney's fees and the cost of any alterations and repairs; second, to
the payment of Base Rent and Additional Rent due and unpaid hereunder; and the
residue, if any, shall be held by Landlord and applied in payment of future Base
Rent and Additional Rent as the same may become due and payable. If any rentals
received from such reletting during any month be less than that to be paid
during that month by Tenant, Tenant shall pay any deficiency to Landlord. If
such rentals are greater than the Base Rent and Additional Rent due under this
Lease, Tenant shall have no claim upon the excess. Such deficiency shall be
calculated and paid monthly. No such reletting of the Premises by Landlord shall
be construed as an election on its part to terminate this Lease unless a written
notice of termination be given to Tenant. Notwithstanding any reletting without
termination, Landlord may at any time elect to terminate this Lease.

     Section 19.3 Notice

     Tenant expressly waives any demand for possession of the Premises or any
notice of intention of Landlord to terminate this Lease or to reenter the
Premises, and Tenant expressly waives any other notice or demand except as may
be required by the Statutes of the Commonwealth of Massachusetts or any other
law.

     Section 19.4 Interest and Late Charge

     All costs incurred by Landlord because of a threatened or actual Event of
Default shall bear interest from the date when the same should have been paid by
Tenant or have been paid by Landlord until paid at the lesser of the highest
annual rate allowed by the laws of the Commonwealth of Massachusetts or at the
rate of eighteen (18%) percent per annum. In the event that Tenant is in
monetary default for more than five (5) days after notice of such default,


                                       17
<PAGE>

then Landlord may elect, in addition to the other remedies available herein, to
collect from Tenant a late charge of four percent (4%) of the delinquent
payment.

     Section 19.5 Waiver of Jury Trial and Assertion of Defenses and
Counterclaim

     Landlord and Tenant waive trial by jury in any action brought in connection
with this Lease. In any action by Landlord relating to the payment of Base Rent
or Additional Rent, Tenant hereby waives any offset, counterclaim or other
defense other than payment. Such claims may only be raised in a separate court
action.

ARTICLE 20 - LIMITATION OF LIABILITY

     Section 20.1 Obligations, Losses and Damages

     Landlord shall have no liability to Tenant to carry out its obligations
under this Lease, nor shall Landlord be liable for any loss or damage for its
failure to carry out such obligations where the failure arises by causes beyond
Landlord's control including Acts of God, emergencies, strikes, labor
difficulties, accidents, civil commotion, fire, catastrophe, war, governmental
requirements and Tenant's actions. In any such event Landlord shall have
additional time at least equal to the period of delay or prevention to remedy
such failure.

     Section 20.2 Repairs

     Landlord shall have no liability to Tenant by reason of any inconvenience,
interruption or injury to business arising from Landlord's making any repairs or
changes to the Property, the Premises and any fixtures, equipment or
appurtenances of the Property or the Premises.

     Section 20.3 Waiver

     Tenant waives all claims including claims for consequential damages against
Landlord arising out of the failure of Landlord from time to time to furnish any
of the services or consents required to be furnished by Landlord under this
Lease. Landlord shall not be liable to Tenant for damage as a result of the
bursting of pipes, leakage of water, and other similar occurrences. Tenant's
sole remedy for any act or omission of Landlord shall be to seek and obtain
injunctive relief.

ARTICLE 21 - NO OTHER WAIVERS OR MODIFICATIONS

     The failure of Landlord to (a) exercise any right or remedies; (b) insist
upon the strict performance of any obligation under this Lease; or (c) exercise
any election herein shall not be a waiver of such right or remedy. Such rights,
remedies and elections shall continue in full force.

ARTICLE 22 - CURING TENANT'S DEFAULTS, ADDITIONAL RENT

     Section 22.1 Curing Tenant's Defaults

     Landlord may, at its sole option, perform any of Tenant's obligations under
this Lease.


                                       18

<PAGE>

     Section 22.2 Additional Rent

     Any expenses incurred by Landlord in connection with the performance by
Landlord of any Tenant's obligations under this Lease including bills for all
costs (including attorneys' fees and their fees for appellate proceedings)
involved in collection of Base Rent or Additional Rent or in enforcing any
rights of Landlord against Tenant under this Lease; and bills for all costs
involved in instituting and prosecuting any summary proceedings may be rendered
by Landlord to Tenant monthly or immediately at Landlord's option, shall be due
and payable as Additional Rent. Additional Rent shall also include any and all
charges payable by Tenant under this Lease except Base Rent.

     Section 22.3 Lien for Rent

     The entire amount of Base Rent and Additional Rent reserved and agreed to
be paid hereunder shall be declared to be a valid lien upon Tenant's interest in
this Lease, the Premises, Tenant's Improvements, Tenant's Property and all of
Tenant's equipment located upon the Premises. In connection therewith, upon
request from Landlord, Tenant shall execute and deliver to Landlord a security
agreement and UCC-1 in form and content satisfactory to Landlord.

ARTICLE 23 - BROKER

     Tenant covenants, warrants and represents to Landlord that Tenant has not
dealt with any real estate broker or salesman in the finding, negotiation or
execution of this Lease other than Trammell Crow Company and Kelleher & Sadowsky
Associates and Tenant shall indemnify Landlord against any claims, costs or
damages arising from any breach of this provision. Landlord covenants, warrants
and represents to Landlord that Tenant has not dealt with any real estate broker
or salesman in the finding, negotiation or execution of this Lease other than
Trammell Crow Company and Kelleher & Sadowsky Associates and Landlord shall
indemnify Tenant against any claims, costs or damages arising from any breach of
this provision. Landlord shall be responsible for paying any broker commissions
to the above brokers in connection with this Lease.

ARTICLE 24 - NOTICES

     All notices or other communications made pursuant to this Lease shall be in
writing and shall be deemed to have been duly given upon the delivery or refusal
to accept to the appropriate addresses by United States certified mail, return
receipt requested, postage prepaid, or via overnight courier service with
receipt confirmation required, addressed as follows:

     If to Landlord:

     Sovereign Bank
     Director of Facilities
     Mail Code: 1 1-900-FP4
     1130 Berkshire Boulevard
     Wyomissing, PA 19610


                                       19

<PAGE>

     If to Tenant:

     World Energy Solutions
     446 Main Street
     14th Floor
     Worcester, Massachusetts 01608

     Or to such other address as either party may designate to the other in
writing.

ARTICLE 25 - ESTOPPEL CERTIFICATE AND PROHIBITION OF RECORDING LEASE

     Section 25.1 Estoppel Certificate

     Within ten (10) days of receipt of a written request for an estoppel
certificate, Tenant shall deliver a statement certifying that this Lease is
unmodified and in full force and effect (or if there are modifications, stating
the modifications and that the Lease is in full force and effect as modified),
certifying the dates to which the Base Rent and Additional Rent have been paid,
stating whether or not Landlord is in default in the performance of any of its
obligations under this Lease and the reasons why, and any other information
reasonably requested to the party requesting the same. The estoppel certificate
may be relied upon by any person to whom it is exhibited or addressed.

     Section 25.2 Lease Not to be Recorded

     In no event shall this Lease or a memorandum hereof be recorded. If the
Tenant records this Lease or a memorandum hereof, Landlord shall have the option
of terminating the Lease, in which event Landlord may hold Tenant liable for all
sums due hereunder. In such event, Tenant grants Landlord a power of attorney,
coupled with an interest, to execute and record a notice clearing title of the
existence of this Lease.

ARTICLE 26 - REPRESENTATIONS AND AGREEMENTS

     Tenant expressly acknowledges that Landlord has not made and is not making,
and Tenant is not relying upon, any warranties, representations, promises or
statements, except to the extent that the same are expressly set forth in this
Lease (including its Exhibits).

ARTICLE 27 - TRANSFER OF LANDLORD'S INTEREST AND LIMITATION OF LIABILITY

     Section 27.1 Transfer of Landlord's Interest

     This Lease shall be binding upon the Tenant and, if permitted by the
Landlord, its successors and assigns. The obligations of Landlord hereunder
shall be binding upon Landlord only during the period Landlord has an interest
in the Property. Thereafter this Lease shall be binding only upon the transferee
of said interest in the Property. Any transferee or assignee of the interest of
Landlord, or any successor thereto, shall be liable for the obligations of
Landlord under this Lease only during the period it has an interest in the
Property.


                                       20

<PAGE>

     Section 27.2 Limitation of Liability

     Tenant shall look only to Landlord's interest in the Property for the
satisfaction of any of Tenant's rights or remedies hereunder. Neither Landlord
nor any employees, officers, stockholders and/or directors of Landlord shall
have any personal liability under this Lease and no other property or assets of
Landlord shall be subject to levy, execution or other enforcement procedure for
the satisfaction of Tenant's rights or remedies under this Lease, the
relationship of Landlord and Tenant, or Tenant's use or occupancy of the
Premises.

ARTICLE 28 - TENANT'S DISCHARGE OF MECHANIC'S LIENS

     Section 28.1 Prevention of Liens

     Tenant shall pay all debts incurred, and shall satisfy all liens of
contractors, subcontractors, mechanics, laborers, and materialmen in respect to
construction, alteration and repair in and on the Premises. Tenant hereby
indemnifies Landlord against all costs and charges, including legal fees in any
"lawsuit" involving any liens, judgments, or encumbrances caused or suffered by
Tenant with respect to the Premises. Tenant shall have no authority to create
any liens for labor or material on or against Landlord's interest in the
Property, and all persons contracting with Tenant for work; or in the Premises,
shall be notified by Tenant that they must look to Tenant and to Tenant's
interest only to secure the payment of any bill or account for work done or
material furnished.

     Section 28.2 Discharge of Liens

     If any mechanic's, laborer's, or materialmen's lien shall at any time be
filed against the Property by reason of any act or omission of Tenant, Tenant,
within fifteen (15) days after notice of the filing thereof, shall cause the
same to be discharged by payment, deposit, bond or order of a court of competent
jurisdiction. If Tenant shall fail to discharge the same, Tenant shall be in
immediate default of this Lease and then Landlord may discharge the lien either
by paying the amount claimed due or by procuring the discharge of such lien by
deposit or by bonding proceedings. Landlord shall be entitled, if Landlord so
elects, to compel the prosecution of an action for the foreclosure of such lien
by the lienor and to pay the amount of the judgment in favor of the lienor with
interest, costs and allowances. Any amount paid by Landlord and all costs and
expenses incurred by Landlord in connection therewith, together with interest
thereon from the date incurred at the highest rate permitted under Massachusetts
law, shall constitute Additional Rent payable by Tenant under this Lease and
shall be paid by Tenant to Landlord on demand.

ARTICLE 29 - INTENTIONALLY OMITTED.

ARTICLE 30 - MISCELLANEOUS

     Section 30.1 Definitions

     The various terms which are defined in other Articles of this Lease or are
defined in Exhibits annexed hereto, shall have the meanings specified for all
purposes of this Lease and all supplemental agreements, unless the context shall
otherwise require.


                                       21

<PAGE>

     The term "including" as used in this Lease means "including but not limited
to". The term "includes" means "includes but not limited to". The term "any"
means "any and all". Singular terms include the plural and plural terms include
the singular.

     Section 30.2 Article Headings

     The Article headings in this Lease are inserted only as a matter of
convenience in reference and are not to be given any effect in construing this
Lease.

     Section 30.3 Ejusdem Generis

     The rule of "ejusdem generis" shall not be applicable to limit a general
statement followed by or referable to an enumeration of specific matters to
matters similar to the matters specifically mentioned.

     Section 30.4 Entire Agreement

     This Lease together with all Exhibits and Riders, if any, sets forth the
entire agreement between the Landlord and Tenant concerning the Premises. There
are no other Agreements between the Landlord and Tenant regarding the Premises
except as contained in this Lease, its Exhibits and Riders. No amendment or
modification of this Lease shall be effective unless it is signed by the party
against whom enforcement of such change is sought.

     Section 30.5 Governing Law

     This Lease shall be governed by and construed in accordance with the laws
of the Commonwealth of Massachusetts.

     Section 30.6 Severability

     If any provision of this Lease is invalid or unenforceable, the remainder
of this Lease shall not be affected by the invalid or unenforceable provision
and shall be enforceable.

     Section 30.7 Submission of Lease

     This Lease is submitted to Tenant solely for Tenant's consideration and
does not constitute an option for leasing the Premises. It shall have no binding
force and effect unless and until Landlord has executed this Lease and delivered
a fully executed copy to Tenant.

     Section 30.8 Holding Over

     If Tenant holds over or occupies the Premises beyond the Term (it being
agreed there shall be no such holding over or occupancy without Landlord's
written consent), no tenancy or interest in the Premises shall result therefrom
but such holding over shall be subject to immediate eviction and removal, and
Tenant shall pay Landlord an amount equal to 150% of the Rent, plus Additional
Rent, for the period during which such hold over continues.


                                       22

<PAGE>

     Section 30.9 Independent Covenants

     Tenant covenants and agrees that, notwithstanding any other provision of
this Lease to the contrary, the obligations of Tenant under this Lease are
covenants which are independent of any covenants or obligations to be performed
by Landlord hereunder; and no breach of any obligations or covenants to be
performed by Landlord hereunder shall give rise to any right of termination of
this Lease by Tenant, or any right to withhold, setoff, abate or otherwise
reduce any monetary or other obligations of Tenant hereunder.

ARTICLE 31 - SECURITY DEPOSIT

     Tenant shall deposit with Landlord at the time of the execution of this
Lease and maintain throughout the Term hereof, a security deposit in the sum of
twelve thousand, seven hundred and sixty Dollars ($12,760.00) as security for
the faithful performance and observance by Tenant of the terms of this Lease. It
is agreed that following an Event of Default Landlord may use, apply or retain
the whole or any part of the security to cure the default or for any sum which
Landlord may expend or may be required to expend by reason of Tenant's default.
In such event, Landlord may require Tenant to deposit additional funds to
replenish the security deposit held by Landlord. Tenant shall deposit such sum
with Landlord within ten (10) days after demand therefor. In the event that
Tenant shall fully comply with this Lease, the security shall be returned to
Tenant within 45 days after the Expiration Date. In the event of a sale or other
disposition of the Land, the Property or the Building, Landlord shall have the
right to transfer the security to the vendee or lessee and, upon written notice
by Landlord, Landlord shall thereafter be released by Tenant from all liability
for the return of such security. Thereafter, Tenant agrees to look solely to the
new Landlord for the return of said security. These provisions shall apply to
every transfer or assignment made of the security. Tenant shall not assign or
encumber or attempt to assign or encumber the security. Neither Landlord nor its
successors or assigns shall be bound by any such assignment, encumbrance,
attempted assignment or attempted encumbrance.

ARTICLE 32 - HAZARDOUS SUBSTANCES

     Section 32.1 Hazardous Waste

     Tenant shall not cause or permit any "hazardous material" (as hereinafter
defined) to be used, stored, transported, released, handled, produced or
installed in, on or from the Premises. "Hazardous Material," as used herein,
shall mean any flammables, explosives, radioactive material, hazardous waste,
hazardous or toxic substances or related materials, asbestos or any material
containing asbestos, or any other substance or material as defined in any
federal, state or local environmental law, ordinance, rule or regulation,
including, without limitation, the Comprehensive Environmental Response
Compensation and Liability Act of 1980, as amended, the Hazardous Material
Transportation Act, as amended, the Resource Conservation and Transportation
Act, as amended, the Resource Conservation and Recovery Act, as amended, and in
the regulations adopted in publications promulgated pursuant to each of the
foregoing. In the event of a breach of the provisions of this section, Landlord
shall have the right, in addition to all other rights and remedies of Landlord
under this Lease or at law, to require Tenant to remove such hazardous materials
from the Premises in the manner prescribed for such removal by law


                                       23

<PAGE>

and requirements of any public authorities. The provisions of this section shall
survive the expiration or any other termination of this Lease.

ARTICLE 33 - PARKING

     Section 33.1 Parking

     Landlord shall provide, or cause to be provided, to Tenant ten (10)
non-reserved automobile parking spaces in the Building Garage at no charge to
the Tenant. Tenant shall pay to Landlord, as of the first day of each month, in
advance at the rates then being charged in said garage. The current rate for
parking spaces in the Building Garage is $75.00 per space per month. Additional
parking spaces in the Building Garage may be available to Tenant based upon
availability. The rate for any additional parking spaces shall be the rate then
being charged for such spaces as adjusted from time to time. Tenant shall notify
Landlord in the event Tenant wishes to obtain such additional parking spaces,
and upon receipt of such inquiry, Landlord shall inquire as to the availability
thereof and notify Tenant of the availability of parking spaces and the current
rate therefore. The parking spaces in the Building Garage shall be made
available to Tenant on 24 hours per day, Monday through Friday (hereinafter
"Garage Hours"). In the event that Tenant and its employees, invitees and guests
shall occupy such spaces after Garage Hours of the Building Garage, the users of
said spaces shall pay the customary charges for said spaces for their after
Garage Hours use until such spaces are vacated.

ARTICLE 34 - [INTENTIONALLY OMITTED]

ARTICLE 35 - EXPANSION OPTION

     If Landlord shall have rentable space available within the Building at any
time during the Term of this Lease and provided Tenant shall not be in default
hereunder, Tenant may, at Tenant's option, offer to lease said rentable space
from Landlord ("Expansion Option"), in its "As Is" condition, without any rent
credit, abatement, or work allowance on the same covenants, terms and conditions
as contained within this Lease, except that: (i) the Base Rent shall be
calculated at a rate equal to 100% of the then fair market value rent, as
determined by the Landlord; and (ii) the Renewal Term shall not include the
Expansion Option provided for herein. Notwithstanding the foregoing, Tenant
acknowledges and agrees that Landlord is under no obligation, whatsoever, to
notify Tenant of available rentable space, nor does this Expansion Option
provide Tenant with a right of first refusal of any rentable space in the
Building, it being understood by the parties that this Expansion Option is
intended to allow Tenant the option to enter into negotiations with Landlord to
lease additional rentable space in the event such space becomes available in the
Building, under the terms and conditions agreed to by both Landlord and Tenant.

ARTICLE 36 - SUBLEASE

     Tenant hereby acknowledges and agrees that this Lease is a sublease and is
subject to a Master Lease between S-BNK WORCESTER, LLC, as Lessor (the
"Masterlandlord") and SOVEREIGN BANK as Lessee, dated as of June 30, 2000 (the
"Masterlease"). This Lease is in all respects subject and subordinate to the
Masterlease, and Tenant shall under no circumstances have any greater rights
with respect to the Demised Premises than Landlord has as Lessee under


                                       24

<PAGE>

the Masterlease. Without limiting the generality of the foregoing, in the event
of the termination or cancellation of the Masterlease for any reason, this
sublease shall automatically terminate effective as of the same day of such
cancellation or termination of the Masterlease, and Landlord shall have no
liability or obligation to Tenant as a result thereof.

                        [Signatures on following page.]


                                       25

<PAGE>

     IN WITNESS WHEREOF, the Landlord and Tenant have executed this Lease for
the purpose herein expressed on the days set forth below.

                                        LANDLORD:

                                        SOVEREIGN BANK


                                        By: /s/ Patti B. Davis
                                            ------------------------------------
                                        Name: Patti B. Davis
                                        Its: Senior Vice President


                                        TENANT:

                                        WORLD ENERGY SOLUTIONS


                                        By: /s/ Richard Domaleski
                                            ------------------------------------
                                        Name: Richard Domaleski
                                        Its: President


                                       26

<PAGE>

                                    EXHIBIT A

                                LEGAL DESCRIPTION

                                  THE PROPERTY

     A certain parcel of land, with the buildings thereon, situated in
WORCESTER, Worcester County, Massachusetts, bounded and described as follows:

Northerly by Pleasant Street three hundred fifty-six and 33/100 (356.33) feet;

Easterly by a jog in said Pleasant Street two and 4/100 (2.04) feet;

Northerly by said Pleasant Street one hundred one and 84/100 (101.84) feet;

Southeasterly by Main Street two hundred ninety-three and 1/100 (293.01) feet;

Southwesterly by the center line of Barton Place two hundred fourteen and 96/100
(214.96) feet as shown on plan hereinafter described;

Southeasterly by the end of Barton Place and by land now or formerly of
Worcester County National Bank as shown on said plan, eighty-six and 44/100
(86.44) feet;

Southwesterly fifteen and 60/100 (15.60) feet;

Southeasterly fourteen and 87/100 (14.87) feet;

Southerly by land now or formerly of the City of Worcester one hundred forty-one
and 63/100 (141.63) feet; Southwesterly by the northeasterly line of Aldrich
Street fifty and 26/100 (50.26) feet;

Northwesterly by land now or formerly of the City of Worcester eighty and 52/100
(80.52) feet; and

Westerly by lot 1 as shown on said plan two hundred twenty and 29/100 (220.29)
feet.

All of said boundaries are determined by the Court to be located as shown on
subdivision plan #36339-B drawn by Thompson-Liston Associates, Inc., Surveyors,
dated December 16, 1982, as modified and approved by the Court, filed in the
Land Registration Office, a copy of a portion of which is filed with Certificate
of Title No. 10263. Being lot 5 on said plan.

     Subject to rights set forth and referred to in a deed given by Howard N.
Feist, Jr. et al Trustees, to Stewart F. Oakes et al Trustees, dated November 3,
1972, duly recorded in Book 5279. Page 88, so far now in force and applicable.

     Subject to and with the benefit of a license from Ransom C. Taylor to
Worcester Electric Light Company (now Massachusetts Electric Company) dated
August 17, 1898, duly recorded in Book 1588. Page 120.


                                       27

<PAGE>

                                   EXHIBIT A-1

                                  THE PREMISES


                                       28

<PAGE>

                                    EXHIBIT B

           CLEANING SERVICES TO BE PERFORMED AT THE LANDLORD'S EXPENSE

     All cleaning services to be provided below either on a nightly or daily
basis will be performed nightly or daily, as the case may be, five (5) nights or
days, as the case may be, per week. Landlord will only provide any of the
cleaning services set forth below on Business Days (as defined in Article 11 of
the Lease), except Saturdays.

     1.   General Cleaning:

          Nightly:

          A.   For all Tenant's areas, empty and clean all waste receptacles,
               removing waste to a designated central location for disposal.
               Clean or damp dust interiors of waste and disposal cans and
               baskets, and wash as necessary.

          B.   Empty and clean all receptacles.

          C.   Hand dust and clean all office furniture, fixtures, window sills
               and shelving that may be reached by cleaning personnel standing
               on floor.

          D.   Dust all moldings, ledges, chair rails, baseboards and trim, damp
               dusting or using treated cloth where necessary.

          E.   Dust under all desk equipment and damp dust or use treated cloth
               on all telephone equipment.

          F.   Wash and disinfect all water coolers.

          G.   Wipe clean all chrome, aluminum and other metal work.

          H.   Sweep all tenant's interior stairways.

     2.   Floors:

          Group A: Ceramic Tile, Marble, Terrazzo

          Group B: Linotile, Asphalt, Koroseal, Plastic Vinyl, Rubber, Wood,
               Cork, or other

          Nightly:

          A.   All floors in Group A to be swept

          B.   All floors in Group B to be swept or dry mopped.

     3.   Vacuuming:


                                       29

<PAGE>

          Nightly:

          A.   Vacuum or carpet sweep all rugs and carpeted areas, moving light
               furniture and office equipment other than desks and file
               cabinets. Special attention to be given reception areas,
               conference rooms and corridors.

     4.   High Dusting: Every Ninety (90) Days:

          A.   Dust all closet shelving and closet floors. Hand dust and clean
               all louvers, grills, etc.

          B.   Damp dust or use treated cloth on all pictures, charts, graphs,
               etc.

          C.   Dust all vertical surfaces such as walls, partitions, door bucks,
               doors and other surfaces. Dust all pipes, ducts, louvers and
               other horizontal surfaces not reached in nightly cleaning.

          D.   Dust all stairwell walls.

          E.   Damp dust or use treated cloth on ceiling air conditioning
               diffusers and wall grills and registers.

          F.   Remove smudges, fingerprints, etc., from walls, doors, door
               jambs, woodwork and light switches nightly.

          G.   Dust or use treated cloth on glass and/or louvers of light
               fixtures.

          H.   Dust clean all directory boards, displays and pictures.

     5.   Washrooms:

          A.   Mop, rinse and dry floors; polish mirrors, clean enameled
               surfaces.

          B.   Wash and disinfect basins, urinals, and bowls using approved
               germicidal detergent solution to remove stains making certain to
               clean undersides of rim of urinals and bowls.

          C.   Wash both sides of all toilet seats with soap and water.

          D.   Damp wipe walls and wash with disinfectants as often as necessary
               but in no event less than every two weeks.

          E.   Supply and service all toilet tissue, tissue to be furnished by
               Landlord.

          F.   Fill soap dispensers and paper towel dispensers (soap and paper
               towels to be furnished by Landlord).


                                       30

<PAGE>

          G.   All wastepaper cans and all receptacles are to be emptied,
               thoroughly cleaned and washed as often as necessary, but not less
               than once every week.

     NOTE: It is the intention to keep these rooms thoroughly clean and not to
use a disinfectant to kill odors.

     6.   Day Service:

          A.   At least once a day, check men's washrooms for soap, towels,
               tissues, etc., wipe out basins and dry mop floors.

          B.   At least once a day, check ladies' washrooms for soap, towels,
               tissues, sanitary napkins and wipe out wash basins and dry mop
               floors.

          C.   Landlord shall supply toilet tissue in both men's and women's
               rooms and sanitary napkins in coin dispensers (which are the
               property of the Landlord) in the women's rooms.

          D.   Dispose of used towels during the day, as necessary.

     7.   General:

          A.   No feather dusters are to be used.

          B.   All lights are to be extinguished and all doors in the demised
               premises as specified by Tenant are to be reopened and locked as
               cleaning is completed.

          C.   All personnel are to be uniformed and clean in appearance during
               business hours.

     8.   Glass:

          A.   Clean inside and outside of all perimeter windows approximately
               two (2) times a year.

          B.   Wipe all interior metal window frames, mullions, terrace doors
               and other unpainted interior metal surfaces of the perimeter
               walls of the Building at the same time that the interior of
               windows are washed.

          C.   Clean all glass in Building lobby, revolving doors and transoms,
               daily.


                                       31

<PAGE>

                                    EXHIBIT C

                              RULES AND REGULATIONS

     1. Tenant will refer all contractors, contractor's representatives and
installation technicians rendering any service for Tenant to Landlord for
Landlord's approval before performance of any such contractual services. This
shall apply to all work performed in the Building including, installation of
telephones, telegraph equipment, electrical services and attachments, and
installations of any and every nature affecting floors, walls, woodwork, trim,
windows, ceilings, equipment or any other physical portion of the Building. None
of this work will be done by Tenant without Landlord's prior written approval.

     2. The work of the cleaning personnel shall not be hindered by Tenant after
5:30 p.m., and such work may be done at any time when the offices are vacant.
The windows, doors and fixtures may be cleaned at any time. Tenant shall provide
adequate waste and rubbish receptacles, cabinets, bookcases, map cases, etc.
necessary to prevent unreasonable hardship to Landlord in discharging its
obligation regarding cleaning service.

     3. Movement in and out of the Building of furniture or office equipment, or
dispatch or receipt by Tenant of any merchandise or material which requires the
use of elevators or stairways, or movement through the building entrances or
lobby, shall be restricted to the hours designated by Landlord from time to
time. All such movement shall be as approved by Landlord in a prearranged manner
to be agreed upon between Tenant and Landlord. Such prearrangement shall include
the time, method, and routing of movement. Tenant expressly assumes all risk or
damage to any and all articles moved, as well as injury to any person or persons
and equipment, property and personnel of Landlord.

     4. No sign or signs will be allowed in any form on the exterior of the
Building or on any window or windows inside or outside of the Building. No sign
or signs, except in uniform location and uniform style, fixed by Landlord, will
be permitted in the public corridors or on corridor doors or entrance to
Tenant's space. All signs shall be constructed by Tenant, at Tenant's sole cost
and expense. Prior written consent from Landlord for any such sign or signs of
Tenant is required.

     5. Tenant shall not place, install or operate in the Premises or in any
part of the Building, any engine, stove or machinery. Tenant shall not conduct
mechanical operations, cook or place or use in or about the Premises any
explosives, gasoline, kerosene, oil, acids, caustics, or any other flammable,
explosive, or hazardous material without the prior written consent of Landlord.

     6. Landlord will not be responsible for any lost or stolen property,
equipment, money or jewelry from the Premises or public rooms regardless of
whether such loss occurs when the item is locked against entry or not.

     7. No birds, animals, bicycles or vehicles shall be brought into or kept in
or about the Building except where required to comply with State and Federal
regulations.


                                       32

<PAGE>

     8. No additional locks shall be placed upon any doors of the Premises
without Landlord's consent. In the event Landlord gives such consent, Tenant
shall provide a key to the Premises to Landlord. Each Tenant shall surrender all
keys to the office on the Expiration Date. Landlord may permit entrance to
Tenant's offices by use of passkeys controlled by Landlord or employees,
contractors, or service personnel, supervised or employed by Landlord.

     9. None of the entries, passages, doors, elevators, elevator doors,
hallways, or stairways shall be blocked or obstructed, or any rubbish, litter,
trash or material of any nature placed, emptied or thrown into these areas, nor
shall such areas be used at any time except for access or egress by Tenant,
Tenant's agents, employees or invitees. Nothing shall be placed on the outside
of the Building, or the windows, exterior windowsills or projections.

     10. Landlord shall have the right to determine and prescribe the weight and
proper position of any unusually heavy furniture including safes, large files,
etc., that are to be placed in the Building. Only those which in the opinion of
Landlord would not do damage to the floors, structure and/or elevators may be
moved into the Building.

     11. No portion of Tenant's area or any other part of the Building shall at
any time be used or occupied as sleeping or lodging quarters.

     12. The sashes, sash doors, windows, glass doors and any lights or
skylights that reflect or admit light into the halls or other places of the
Building, shall not be covered or obstructed by Tenant nor shall anything be
placed upon or hung from the window-sills. The water and wash closets and
urinals shall not be used for any other purpose than the purpose for which they
were respectively constructed, and the expense of any breakage, stoppage or
damage resulting from a violation of this rule shall be borne by the Tenant
whose clerks, agents, servants or licensees shall have caused it. No Tenant
shall mark, paint, drill into or in any way deface the walls, ceilings,
partitions, floors, wood, stone or iron work, or make or permit any improper
noises in the Building.

     13. Only persons authorized by the Landlord shall be permitted to furnish
ice, drinking water, towel and other similar services to Tenant, and only at
hours and under regulations fixed by the Landlord. No Tenant shall employ any
person or persons, other than the cleaning personnel of the Landlord for the
purpose of cleaning the Premises. Tenant shall close the windows and lock the
doors before leaving the Building each day.

     14. No window shades, blinds or drapes will be placed on any of the windows
except with the prior written approval of the Landlord. No awnings will be
allowed on any of the windows.

     15. The Landlord shall have the right to prohibit any advertising by any
Tenant, which, in its opinion, tends to impair the reputation of the Building or
its desirability as a building for offices for financial, insurance and other
institutions and businesses of like nature, and upon written notice from
Landlord, Tenant shall refrain from or discontinue such advertising.

     16. Access may be had by the Tenant to the halls, corridors, elevators and
stairways, in the Building, and to the offices leased by them at any time or
times during business hours on


                                       33

<PAGE>

business days. During other hours access to the Building may be refused unless
the person seeking admission is known to the watchman in charge, or has a pass
or is properly identified. The Landlord shall in no case be liable in damages
for the admission or exclusion of any person from the Building. In case of
invasion, mob riot, public excitement or other commotion, the Landlord reserves
the right to prevent access to the Building during the continuance of same by
closing the doors or otherwise for the safety of the tenants and protection of
property in the Building.

     17. Tenant agrees not to install food or drink vending machines or any
other food service equipment.

     18. Each tenant has an obligation to ensure that its employees, invitees,
licensees, agents and any other visitors, conduct themselves in a professional
and businesslike manner. Tenant, as well as, employees and visitors of Tenant
shall:

     (i)  refrain from making excessive noise in all areas of the Building;

     (ii) refrain from using inappropriate language in all common areas of the
          Building;

     (iii) not congregate in the common areas of the Building;

     (iv) limit the use of the restrooms to those in Tenant's employment and
          clients; and

     (v)  not use the Building restrooms for the changing of clothing.

     Landlord desires to maintain high standards for the Building in order to
assure an environment of comfort and convenience for its tenants. It will be
appreciated if any undesirable conditions or lack of courtesy or attention by
its employees is reported directly to Landlord.


                                       34

<PAGE>

                                    EXHIBIT D

                                 LANDLORD'S WORK

     Landlord shall construct to building standard, a reception area, 7-8
offices, a conference room and a break room, all in accordance with plans agreed
upon between Landlord and Tenant. See attached plan dated 7/16/04 and meeting
minutes dated 8/30/04 that reflect agreed upon modifications to plan.


                                       35