CREDIT AGREEMENT

        THIS CREDIT AGREEMENT (this “Agreement”) is entered into as of March 18,
2008, by and between ORION ENERGY SYSTEMS, INC., a Wisconsin corporation and
GREAT LAKES ENERGY TECHNOLOGIES, LLC, a Wisconsin limited liability company
(each individually, a “Borrower”), and WELLS FARGO BANK, NATIONAL ASSOCIATION
(“Bank”). Each reference herein to “Borrower” shall mean each and every party,
collectively and individually, defined above as a Borrower.

RECITALS

        A.     Bank, through its Wells Fargo Business Credit operating division,
extended to Borrower certain credit facilities pursuant to the terms of a Credit
and Security Agreement dated December 22, 2005 (as amended, the “WFBC
Agreement”).

        B.     Bank and Borrower have now agreed that from and after the date of
this Agreement, the credit facilities extended by Bank shall be extended by its
Commercial Banking Group operating division, rather than by its Wells Fargo
Business Credit operating division, and Bank and Borrower have agreed to such
credit on the terms and conditions contained in this Agreement, which shall
terminate and replace the WFBC Agreement. Any ancillary agreements between Bank
and Borrower other than this Agreement shall continue in full force and effect
unless explicitly replaced or terminated by Bank and Borrower in writing.

        NOW, THEREFORE, for valuable consideration, the receipt and sufficiency
of which are hereby acknowledged, Bank and Borrower hereby agree that this
Agreement shall terminate and replace the WFBC Agreement, and further agree as
follows:

ARTICLE I
CREDIT TERMS

        SECTION 1.1.    LINE OF CREDIT.

        (a)    Line of Credit; Discretionary Increases to Line of Credit.
Subject to the terms and conditions of this Agreement, Bank hereby agrees to
make advances to Borrower from time to time up to and including August 31, 2010,
not to exceed at any time the aggregate principal amount of TWENTY FIVE MILLION
DOLLARS ($25,000,000.00)(“Line of Credit”), the proceeds of which shall be used
for working capital or other general corporate purposes. Borrower’s obligation
to repay advances under the Line of Credit shall be evidenced by a
$25,000,000.00 promissory note dated the same date as this Agreement (“Line of
Credit Note”), the terms of which are incorporated by reference. The Line of
Credit Note shall be given as a replacement for, and not in satisfaction of, the
Borrower’s $25,000,000 Revolving Note dated December 22, 2005.

        Borrower may request an increase in the Line of Credit by up to an
additional TWENTY FIVE MILLION DOLLARS ($25,000,000.00), provided that after
giving effect to the requested increase, the aggregate amount of the Line of
Credit does not exceed $50,000,000.00. Borrower may request such an increase
once in the minimum amount of at least $1,000,000.00. Following Borrower’s
request, Bank may increase the amount of the Line of Credit, provided that on or
before the proposed date of the effectiveness of the increase, Borrower provides
Bank (i) pro-forma projections for the next four fiscal quarters, (ii) a current
compliance certificate executed by an officer of Borrower acceptable to Bank
both showing that Borrower is and will in the future be compliance with the
terms and conditions of this Agreement, and (iii) a replacement Line of Credit
Note for the full amount of the increased Line of Credit. The amount of the Line
of Credit in excess of $25,000,000.00 is a discretionary Line of Credit, and
Wells Fargo has no obligation to make an advance even if no Event of Default has
occurred under the terms of this Agreement.

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        (b)    Limitation on Borrowings. Outstanding borrowings under the Line
of Credit, whether before or after any increase to the amount of the Line of
Credit, shall not at any time exceed a borrowing base consisting of the
aggregate of (i) eighty percent (80%) of Borrower’s Eligible Accounts, plus (ii)
fifty percent (50%) of the value of Borrower’s Eligible Inventory or
$10,000,000, whichever is less, and less (iii) an amount equal to the Borrowing
Base Reserve.

        The foregoing shall be determined by Bank upon receipt and review of all
collateral reports required hereunder and such other documents and collateral
information as Bank may from time to time require. Borrower acknowledges that
said borrowing base was established by Bank with the understanding that, among
other items, the aggregate of all returns, rebates, discounts, credits and
allowances for the immediately preceding three (3) months at all times shall be
less than five percent (5%) of Borrower’s gross sales for said period. If such
dilution of Borrower’s accounts for the immediately preceding three (3) months
at any time exceeds five percent (5%) of Borrower’s gross sales for said period,
or if there at any time exists any other matters, events, conditions or
contingencies which Bank reasonably believes may affect payment of any portion
of Borrower’s accounts, Bank, in its sole reasonable discretion, may reduce the
foregoing advance rate against eligible accounts receivable to a percentage
appropriate to reflect such additional dilution and/or establish additional
reserves against Borrower’s eligible accounts receivable.

        “Borrowing Base Reserve” means, as of any date of determination, an
amount or a percent of a specified category or item that Bank establishes in its
sole reasonable discretion from time to time to reduce availability under the
borrowing base (i) to reflect without limitation events, conditions,
contingencies, litigation or other risks which affect the assets, financial
performance, business or prospects of Borrower, or the collateral securing the
indebtedness or its value, or the enforceability, perfection or priority of
Bank’s security interest in the collateral, or (ii) to reflect Bank’s judgment
that any information relating to Borrower, its financial condition or
collateral, may be incomplete, inaccurate or misleading in any material respect,
or may have materially changed in a way that may not otherwise be meaningfully
measured by existing financial covenants.

        “Eligible Accounts” means all unpaid Accounts of the Borrower arising
from the sale or lease of goods or the performance of services, net of any
credits, but excluding any such Accounts having any of the following
characteristics:

        (i)     That portion of Accounts unpaid 90 days or more after the
invoice date or, if the Bank in its reasonable discretion has determined that a
particular dated Account may be eligible, that portion of such Account which is
unpaid more than sixty (60) days past the stated due date or more than one
hundred twenty (120) days past the invoice date;

        (ii)     That portion of Accounts related to goods or services with
respect to which the Borrower has received notice of a claim or dispute, which
are subject to a claim of offset or a contra account, or which reflect a
reasonable reserve for warranty claims or returns;

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        (iii)     That portion of Accounts not yet earned by the final delivery
of goods or rendition of services, as applicable, by the Borrower to the
customer, including progress billings, and that portion of Accounts for which an
invoice has not been sent to the applicable account debtor;

        (iv)     Accounts constituting (i) proceeds of copyrightable material
unless such copyrightable material shall have been registered with the United
States Copyright Office, or (ii) proceeds of patentable inventions unless such
patentable inventions have been registered with the United States Patent and
Trademark Office;

        (v)     Accounts owed by any unit of government, whether foreign or
domestic (provided, however, that there shall be included in Eligible Accounts
that portion of Accounts owed by such units of government for which the Borrower
has provided evidence satisfactory to the Bank that (A) the Bank has a first
priority perfected security interest and (B) such Accounts may be enforced by
the Bank directly against such unit of government under all applicable laws);

        (vi)     Accounts owed by an account debtor located outside the United
States which are not (A) backed by a bank letter of credit naming the Bank as
beneficiary or assigned to the Bank, in the Bank’s possession or control, and
with respect to which a control agreement concerning the letter-of-credit rights
is in effect, and acceptable to the Bank in all respects, in its sole reasonable
discretion, or (B) covered by a foreign receivables insurance policy acceptable
to the Bank in its sole reasonable discretion;

        (vii)     Accounts owed by an account debtor that is insolvent, the
subject of bankruptcy proceedings or has gone out of business;

        (viii)     Accounts owed by an Owner, Subsidiary, Affiliate, Officer or
employee of the Borrower or by Northland Capital;

        (ix)     Accounts not subject to a duly perfected security interest in
the Bank’s favor or which are subject to any Lien in favor of any Person other
than the Bank;

        (x)     That portion of Accounts that has been restructured, extended,
amended or modified;

        (xi)     Accounts owed by an account debtor, regardless of whether
otherwise eligible, to the extent that the aggregate balance of such Accounts
exceeds twenty five percent (25%) of the aggregate amount of all
EligibleAccounts;

        (xii)     Accounts owed by an account debtor, regardless of whether
otherwise eligible, if twenty percent (20%) or more of the total amount of
Accounts due from such debtor is ineligible under clauses (i), (ii), or (x)
above; and

        (xiii)     Accounts, or portions thereof, otherwise deemed ineligible by
the Bank in its sole reasonable discretion.

        “Eligible Inventory” means all Inventory of the Borrower, valued at the
lower of cost or market in accordance with GAAP; but excluding any Inventory
having any of the following characteristics:

        (i)     Inventory that is: in-transit; located at any warehouse, job
site or other premises not approved by the Bank in writing; not subject to a
duly perfected first priority security interest in the Bank’s favor; subject to
any lien or encumbrance that is subordinate to the Bank’s first priority
security interest; covered by any negotiable or non-negotiable warehouse
receipt, bill of lading or other document of title; on consignment from any
Person; on consignment to any Person or subject to any bailment unless such
consignee or bailee has executed an agreement with the Bank;

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        (ii)     Supplies, packaging, fabricated parts, sample Inventory, or
customer supplied parts or Inventory;

        (iii)     Work-in-process Inventory;

        (iv)     Inventory that is damaged, defective, obsolete, slow moving or
not currently saleable in the normal course of the Borrower’s operations, or the
amount of such Inventory that has been reduced by shrinkage;

        (v)     Inventory that the Borrower has returned, has attempted to
return, is in the process of returning or intends to return to the vendor
thereof;

        (vi)     Inventory that is perishable or live;

        (vii)     Inventory manufactured by the Borrower pursuant to a license
unless the applicable licensor has agreed in writing to permit the Bank to
exercise its rights and remedies against such Inventory;

        (viii)     Inventory that is subject to a Lien in favor of any Person
other than the Bank; and

        (ix)     Inventory otherwise deemed ineligible by the Bank in its sole
reasonable discretion.

        (c)    Letter of Credit Subfeature. As a subfeature under the Line of
Credit, Bank agrees from time to time during the term thereof to issue or cause
an affiliate to issue standby letters of credit for the account of Borrower
(each, a “Letter of Credit” and collectively, “Letters of Credit”); provided
however, that the aggregate undrawn amount of all outstanding Letters of Credit
shall not at any time exceed TEN MILLION DOLLARS ($10,000,000.00). The form and
substance of each Letter of Credit shall be subject to approval by Bank, in its
sole discretion. No Letter of Credit shall have an expiration date subsequent to
the maturity date of the Line of Credit. The undrawn amount of all Letters of
Credit shall be reserved under the Line of Credit and shall not be available for
borrowings thereunder. Each Letter of Credit shall be subject to the additional
terms and conditions of the Letter of Credit agreements, applications and any
related documents required by Bank in connection with the issuance thereof. Each
drawing paid under a Letter of Credit shall be deemed an advance under the Line
of Credit and shall be repaid by Borrower in accordance with the terms and
conditions of this Agreement applicable to such advances; provided however, that
if advances under the Line of Credit are not available, for any reason, at the
time any drawing is paid, then Borrower shall immediately pay to Bank the full
amount drawn, together with interest thereon from the date such drawing is paid
to the date such amount is fully repaid by Borrower, at the rate of interest
applicable to advances under the Line of Credit. In such event Borrower agrees
that Bank, in its sole discretion, may debit any account maintained by Borrower
with Bank for the amount of any such drawing.

        (d)    Borrowing and Repayment. Borrower may from time to time during
the term of the Line of Credit borrow, partially or wholly repay its outstanding
borrowings, and reborrow, subject to all of the limitations, terms and
conditions contained herein or in the Line of Credit Note; provided however,
that the total outstanding borrowings under the Line of Credit shall not at any
time exceed the maximum principal amount available thereunder, as set forth
above.

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        SECTION 1.2.    INTEREST/FEES.

        (a)    Interest. The outstanding principal balance of each credit
subject hereto shall bear interest, and the amount of each drawing paid under
the Standby Letter of Credit shall bear interest from the date such drawing is
paid to the date such amount is fully repaid by Borrower, at the rate of
interest set forth in each promissory note or other instrument or document
executed in connection therewith..

        (b)    Computation and Payment. Interest shall be computed on the basis
of a 360-day year, actual days elapsed. Interest shall be payable at the times
and place set forth in each promissory note or other instrument or document
required hereby.

        (c)    Unused Commitment Fee. Borrower shall pay to Bank a fee equal to
twenty hundredths percent (0.20%) per annum (computed on the basis of a 360-day
year, actual days elapsed) on the average daily unused amount of the Line of
Credit, which fee shall be calculated on a quarterly basis by Bank and shall be
due and payable by Borrower in arrears on the date of this agreement. In the
event that Borrower increases the Line of Credit pursuant to the terms of this
Agreement, then the fee shall be calculated on the full amount of the increased
Line of Credit.

        (d)    Letter of Credit Fees. Borrower shall pay to Bank (i) fees upon
the issuance of each Letter of Credit equal to one and one quarter percent
(1.25%) per annum (computed on the basis of a 360-day year, actual days elapsed)
of the face amount thereof, and (ii) fees upon the payment or negotiation of
each drawing under any Letter of Credit and fees upon the occurrence of any
other activity with respect to any Letter of Credit (including without
limitation, the transfer, amendment or cancellation of any Letter of Credit)
determined in accordance with Bank’s standard fees and charges then in effect
for such activity.

        (e)    Line of Credit Termination Fee. Borrower shall pay Bank a fee
equal to 1.0% of the principal amount of the Line of Credit then in effect if
Borrower prepays and terminates the Line of Credit prior to December 23, 2008,
which fee shall be payable by Borrower prior to the release by Bank of its lien
on the Borrower’s assets.

        SECTION 1.3.    COLLECTION OF PAYMENTS. Borrower authorizes Bank to
collect all interest due under each credit subject hereto by charging Borrower’s
deposit account number 4121228985 with Bank, or any other deposit account
maintained by Borrower with Bank, for the full amount thereof. Should there be
insufficient funds in any such deposit account to pay all such sums when due,
the full amount of such deficiency shall be immediately due and payable by
Borrower.

        SECTION 1.4.    COLLATERAL. As security for all indebtedness and other
obligations of Borrower to Bank, Borrower grants Bank a first lien security
interest in all Borrower’s accounts receivable and other rights to payment,
general intangibles and inventory, and Borrower also grants to Bank a security
interests of second lien priority in all Borrower’s equipment and fixtures.

        All of the foregoing shall be evidenced by and subject to the terms of
such security agreements, financing statements and other documents as Bank shall
reasonably require, all in form and substance satisfactory to Bank. Borrower
shall pay to Bank immediately upon demand the full amount of all charges, costs
and expenses (to include fees paid to third parties and all allocated costs of
Bank personnel), expended or incurred by Bank in connection with any of the
foregoing security, including without limitation, filing and recording fees and
costs of appraisals and audits.

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ARTICLE II
REPRESENTATIONS AND WARRANTIES

        Each Borrower makes the following representations and warranties to
Bank, which shall survive the execution of this Agreement and continue in full
force and effect until the full and final payment, and satisfaction and
discharge, of all obligations of each Borrower to Bank subject to this
Agreement.

        SECTION 2.1.    LEGAL STATUS.

        Borrower Orion Energy Systems, Inc. is a corporation, duly organized and
existing and in good standing under the laws of Wisconsin, and is qualified or
licensed to do business (and is in good standing as a foreign corporation, if
applicable) in all jurisdictions in which such qualification or licensing is
required or in which the failure to so qualify or to be so licensed could have a
material adverse effect on Borrower.

        Borrower Great Lakes Energy Technologies, LLC is a limited liability
company, duly organized and existing and in good standing under the laws of
Wisconsin, and is qualified or licensed to do business (and is in good standing
as a foreign corporation, if applicable) in all jurisdictions in which such
qualification or licensing is required or in which the failure to so qualify or
to be so licensed could have a material adverse effect on Borrower.

        SECTION 2.2.    AUTHORIZATION AND VALIDITY. This Agreement and each
promissory note, contract, instrument and other document required hereby or at
any time hereafter delivered to Bank in connection herewith (collectively, the
“Loan Documents”) have been duly authorized, and upon their execution and
delivery in accordance with the provisions hereof will constitute legal, valid
and binding agreements and obligations of each Borrower, enforceable in
accordance with their respective terms.

        SECTION 2.3.    NO VIOLATION. The execution, delivery and performance by
each Borrower of the Loan Documents and does not violate any provision of any
law or regulation, or contravene any provision of the Articles of Incorporation
or By-Laws, or Articles of Organization or Operating Agreement of, each
Borrower, or result in any breach of or default under any contract, obligation,
indenture or other instrument to which either Borrower is a party or by which
either Borrower may be bound.

        SECTION 2.4.    LITIGATION. There are no pending, or to the best of each
Borrower’s knowledge, threatened actions, claims, investigations, suits or
proceedings by or before any governmental authority, arbitrator, court or
administrative agency which could have a material adverse effect on the
financial condition or operation of either Borrower, other than those disclosed
to Bank in writing prior to the date hereof, the disclosure of which shall not
be considered the waiver of any rights of Bank hereunder at any time in the
future.

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        SECTION 2.5.     CORRECTNESS OF FINANCIAL STATEMENT. The annual
financial statement of each Borrower dated March 31, 2007, and all interim
financial statements delivered to Bank since said date, true copies of which
have been delivered by each Borrower to Bank prior to the date hereof, (a) are
complete and correct and present fairly the financial condition of each
Borrower, (b) disclose all liabilities of each Borrower that are required to be
reflected or reserved against under generally accepted accounting principles,
whether liquidated or unliquidated, fixed or contingent, and (c) have been
prepared in accordance with generally accepted accounting principles
consistently applied. Since the dates of such financial statements there has
been no material adverse change in the financial condition of each Borrower, nor
has either Borrower mortgaged, pledged, granted a security interest in or
otherwise encumbered any of its assets or properties except in favor of Bank or
as otherwise permitted by Bank in writing.

        SECTION 2.6.    INCOME TAX RETURNS. Each Borrower has no knowledge of
any pending assessments or adjustments of its income tax payable with respect to
any year.

        SECTION 2.7.    NO SUBORDINATION. There is no agreement, indenture,
contract or instrument to which either Borrower is a party or by which either
Borrower may be bound that requires the subordination in right of payment of any
of that Borrower’s obligations subject to this Agreement to any other obligation
of either Borrower.

        SECTION 2.8.    PERMITS, FRANCHISES. Each Borrower possesses, and will
hereafter possess, all permits, consents, approvals, franchises and licenses
required and rights to all trademarks, trade names, patents, and fictitious
names, if any, necessary to enable it to conduct the business in which it is now
engaged in compliance with applicable law.

        SECTION 2.9.    ERISA. Each Borrower is in compliance in all material
respects with all applicable provisions of the Employee Retirement Income
Security Act of 1974, as amended or recodified from time to time (“ERISA”); each
Borrower has not violated any provision of any defined employee pension benefit
plan (as defined in ERISA) maintained or contributed to by each Borrower (each,
a “Plan”); no Reportable Event as defined in ERISA has occurred and is
continuing with respect to any Plan initiated by Borrower; each Borrower has met
its minimum funding requirements under ERISA with respect to each Plan; and each
Plan will be able to fulfill its benefit obligations as they come due in
accordance with the Plan documents and under generally accepted accounting
principles.

        SECTION 2.10.    OTHER OBLIGATIONS. Each Borrower is not in default on
any obligation for borrowed money, any purchase money obligation or any other
material lease, commitment, contract, instrument or obligation.

        SECTION 2.11.    ENVIRONMENTAL MATTERS. Except as disclosed by either
Borrower to Bank in writing prior to the date hereof, each Borrower is in
compliance in all material respects with all applicable federal or state
environmental, hazardous waste, health and safety statutes, and any rules or
regulations adopted pursuant thereto, which govern or affect any of that
Borrower’s operations and/or properties, including without limitation, the
Comprehensive Environmental Response, Compensation and Liability Act of 1980,
the Superfund Amendments and Reauthorization Act of 1986, the Federal Resource
Conservation and Recovery Act of 1976, and the Federal Toxic Substances Control
Act, as any of the same may be amended, modified or supplemented from time to
time. None of the operations of either Borrower is the subject of any federal or
state investigation evaluating whether any remedial action involving a material
expenditure is needed to respond to a release of any toxic or hazardous waste or
substance into the environment. Each Borrower has no material contingent
liability in connection with any release of any toxic or hazardous waste or
substance into the environment.

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ARTICLE III
CONDITIONS

        SECTION 3.1.    CONDITIONS OF INITIAL EXTENSION OF CREDIT. The
obligation of Bank to extend any credit contemplated by this Agreement is
subject to the fulfillment to Bank’s satisfaction of all of the following
conditions:

        (a)    Approval of Bank Counsel. All legal matters incidental to the
extension of credit by Bank shall be satisfactory to Bank’s counsel.

        (b)    Documentation. Bank shall have received, in form and substance
satisfactory to Bank, each of the following, duly executed:

  (i) This Agreement and each promissory note or other instrument or document
required hereby.

  (ii) Certificate of Incumbency.

  (iii) Corporate Resolution: Borrowing.

  (iv) Limited Liability Co. Cert: Borrowing.

  (v) Security Agreement: Equipment & Fixtures.

  (vi) Security Agreement: Continuing Rights to Payments and Inventory.

  (vii) Intercreditor Agreement dated December 23, 2005 entered into with
Hometown Bank.

  (viii) Security Interest Subordination Agreement dated December 22, 2005
entered into with City of Manitowoc, Wisconsin.

  (ix) Copies of all policies of insurance of every kind and description.

  (x) Such other documents as Bank may require under any other Section of this
Agreement.

        (c)    Financial Condition. There shall have been no material adverse
change, as determined by Bank, in the financial condition or business of
Borrower, nor any material decline, as determined by Bank, in the market value
of any collateral required hereunder or a substantial or material portion of the
assets of Borrower.

        (d)    Insurance. Borrower shall have delivered to Bank evidence of
insurance coverage on all Borrower’s property, in form, substance, amounts,
covering risks and issued by companies satisfactory to Bank, and where required
by Bank, with loss payable endorsements in favor of Bank.

        SECTION 3.2.    CONDITIONS OF EACH EXTENSION OF CREDIT. The obligation
of Bank to make each extension of credit requested by Borrower hereunder shall
be subject to the fulfillment to Bank’s satisfaction of each of the following
conditions:

        (a)    Compliance. The representations and warranties contained herein
and in each of the other Loan Documents shall be true on and as of the date of
the signing of this Agreement and on the date of each extension of credit by
Bank pursuant hereto, with the same effect as though such representations and
warranties had been made on and as of each such date, and on each such date, no
Event of Default as defined herein, and no condition, event or act which with
the giving of notice or the passage of time or both would constitute such an
Event of Default, shall have occurred and be continuing or shall exist.

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        (b)    Documentation. Bank shall have received all additional documents
which may be required in connection with such extension of credit.

        (c)    Additional Letter of Credit Documentation. Prior to the issuance
of each Letter of Credit, Bank shall have received a Letter of Credit Agreement,
properly completed and duly executed by borrower.

ARTICLE IV
AFFIRMATIVE COVENANTS

        Each Borrower covenants that so long as Bank remains committed to extend
credit to Borrower pursuant hereto, or any liabilities (whether direct or
contingent, liquidated or unliquidated) of Borrower to Bank under any of the
Loan Documents remain outstanding, and until payment in full of all obligations
of Borrower subject hereto, each Borrower shall, unless Bank otherwise consents
in writing:

        SECTION 4.1. PUNCTUAL PAYMENTS. Punctually pay all principal, interest,
fees or other liabilities due under any of the Loan Documents at the times and
place and in the manner specified therein, and immediately upon demand by Bank,
the amount by which the outstanding principal balance of any credit subject
hereto at any time exceeds any limitation on borrowings applicable thereto.

        SECTION 4.2.    ACCOUNTING RECORDS. Maintain adequate books and records
in accordance with generally accepted accounting principles consistently
applied, and permit any representative of Bank, at any reasonable time, to
inspect, audit and examine such books and records, to make copies of the same,
and to inspect the properties of Borrower.

        SECTION 4.3.    FINANCIAL STATEMENTS AND FINANCIAL INFORMATION. Provide
to Bank all of the following, in form and detail satisfactory to Bank:

        (a)     not later than 120 days after and as of the end of each fiscal
year, an audited consolidated financial statement of Borrower, prepared by a
certified public accountant acceptable to bank, to include balance sheet and
income statement;

        (b)     not later than 30 days after and as of the end of each month, a
financial statement of Borrower, prepared by Borrower, to include balance sheet
and income statement;

        (c)     not later than 20 days after and as of the end of each month, a
borrowing base certificate, an inventory collateral report, an aged listing of
accounts receivable and accounts payable, and a reconciliation of accounts, and
to be delivered each January and July if there were at any time borrowings in
the preceding six months, a list of the names and addresses of all Borrower’s
account debtors;

        (d)     not later than each March 31 annual projections, to include
balance sheet, income statement and statement of cash flows;

        (e)     contemporaneously with each annual and monthly financial
statement of Borrower required hereby, a certificate of an authorized officer,
manager or member of Borrower that said financial statements are accurate and
that there exists no Event of Default nor any condition, act or event which with
the giving of notice or the passage of time or both would constitute an Event of
Default;

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        (f)     Notice of any litigation or other adversarial proceedings in any
court or other forum where the amount being claimed against Borrower is in
excess of $500,000.00, and promptly upon receipt, and in any event no more than
ten (10) days after filing or receipt, copies of all pleadings, notices, court
papers, or motions concerning a dispositive issue filed by any party with
respect to such litigation or other adversarial proceedings, and copies of any
order or judgment filed by the court, with respect to such litigation or
proceedings, together with any non-privileged discovery materials that Bank in
its sole discretion deems appropriate for its review..

        (g)     Notice of any reservation of rights or of any refusal to cover
any claims made against Borrower or any officers or employees of Borrower under
any policies of insurance.

        (h)     from time to time such other information as Bank may reasonably
request.

        SECTION 4.4.    COMPLIANCE. Preserve and maintain all licenses, permits,
governmental approvals, rights, privileges and franchises necessary for the
conduct of its business; and comply with the provisions of all documents
pursuant to which Borrower is organized and/or which govern Borrower’s continued
existence and with the requirements of all laws, rules, regulations and orders
of any governmental authority applicable to Borrower and/or its business.

        SECTION 4.5.    INSURANCE. Maintain and keep in force, for each business
in which Borrower is engaged, insurance of the types and in amounts customarily
carried in similar lines of business, including but not limited to fire,
extended coverage, public liability, flood, property damage and workers’
compensation, with all such insurance in amounts satisfactory to Bank, and
deliver to Bank from time to time at Bank’s request schedules setting forth all
insurance then in effect. Such insurance may be obtained from an insurer or
through an insurance agent of Borrower’s choice, provided that any insurer
chosen by Borrower is acceptable to Bank on such reasonable grounds as may be
permitted under applicable law.

        SECTION 4.6.    FACILITIES. Keep all properties useful or necessary to
Borrower’s business in good repair and condition, and from time to time make
necessary repairs, renewals and replacements thereto so that such properties
shall be fully and efficiently preserved and maintained.

        SECTION 4.7.    TAXES AND OTHER LIABILITIES. Pay and discharge when due
any and all indebtedness, obligations, assessments and taxes, both real or
personal, including without limitation federal and state income taxes and state
and local property taxes and assessments, except (a) such as Borrower may in
good faith contest or as to which a bona fide dispute may arise, and (b) for
which Borrower has made provision, to Bank’s satisfaction, for eventual payment
thereof in the event Borrower is obligated to make such payment.

        SECTION 4.8.    LITIGATION. Promptly give notice in writing to Bank of
any litigation pending or threatened against Borrower.

        SECTION 4.9.    FINANCIAL CONDITION. Maintain Borrower’s financial
condition as follows using generally accepted accounting principles consistently
applied and used consistently with prior practices (except to the extent
modified by the definitions herein), with compliance determined commencing with
Borrower’s financial statements for the period ending December 31, 2007:

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        (a)     Total Liabilities divided by Tangible Net Worth not greater than
1.0 to 1.0 at each fiscal quarter end, with “Total Liabilities” defined as the
aggregate of current liabilities and non-current liabilities less subordinated
debt, and with “Tangible Net Worth” defined as the aggregate of total
stockholders’ and members’ equity plus subordinated debt less any intangible
assets.

        (b)     Net income after taxes not less than $1.00 on a rolling
4-quarter basis, determined as of each fiscal quarter end.

        (c)     Fixed Charge Coverage Ratio not less than 2.00 to 1.0 as of each
fiscal quarter end, determined on a rolling 4-quarter basis, with “Fixed Charge
Coverage Ratio” defined as the aggregate of net profit after taxes plus
depreciation expense, amortization expense, cash capital contributions and
increases in subordinated debt minus dividends, distributions and decreases in
subordinated debt, divided by the aggregate of the current maturity of long-term
debt and capitalized lease payments.

        SECTION 4.10.    NOTICE TO BANK. Promptly (but in no event more than
five (5) days after the occurrence of each such event or matter) give written
notice to Bank in reasonable detail of: (a) the occurrence of any Event of
Default, or any condition, event or act which with the giving of notice or the
passage of time or both would constitute an Event of Default; (b) any change in
the name or the organizational structure of Borrower; (c) the occurrence and
nature of any Reportable Event or Prohibited Transaction, each as defined in
ERISA, or any funding deficiency with respect to any Plan; or (d) any
termination or cancellation of any insurance policy which Borrower is required
to maintain, or any uninsured or partially uninsured loss through liability or
property damage, or through fire, theft or any other cause affecting Borrower’s
property.

ARTICLE V
NEGATIVE COVENANTS

        Borrower further covenants that so long as Bank remains committed to
extend credit to Borrower pursuant hereto, or any liabilities (whether direct or
contingent, liquidated or unliquidated) of Borrower to Bank under any of the
Loan Documents remain outstanding, and until payment in full of all obligations
of Borrower subject hereto, Borrower will not without Bank’s prior written
consent:

        SECTION 5.1.    USE OF FUNDS. Use any of the proceeds of any credit
extended hereunder except for the purposes stated in Article I hereof.

        SECTION 5.2.    CAPITAL EXPENDITURES. Make any additional investment in
fixed assets in any fiscal year in an amount in excess of $5,000,000, or, with
respect to capital expenditures used for the Borrower’s tech center expansion on
Mirro Drive in Manitowoc, Wisconsin, in an amount in excess of $8,500,000.

        SECTION 5.3.    LEASE EXPENDITURES. Incur operating lease expense in any
fiscal year in an amount in excess of $2,500,000.

        SECTION 5.4.    OTHER INDEBTEDNESS. Create, incur, assume or permit to
exist any indebtedness or liabilities resulting from borrowings, loans or
advances, whether secured or unsecured, matured or unmatured, liquidated or
unliquidated, joint or several, except (a) the liabilities of Borrower to Bank,
(b) indebtedness incurred for the purchase of equipment in an amount not in
excess of $2,000,000, and (c) any other liabilities of Borrower existing as of,
and disclosed to Bank prior to, the date hereof.

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        SECTION 5.5.    MERGER, CONSOLIDATION, TRANSFER OF ASSETS. Merge into or
consolidate with any other entity; make any substantial change in the nature of
Borrower’s business as conducted as of the date hereof; acquire all or
substantially all of the assets of any other entity, except up to $25,000,000 in
cash or stock per annum, assuming Borrower is currently not in default and the
acquisition does not cause a default on a historical or pro-forma basis with the
covenants established. The limit shall be reduced to $10,000,000 if the
contemplated acquisition requires the use of the Revolving Line of Credit to
complete the acquisition; nor sell, lease, transfer or otherwise dispose of all
or a substantial or material portion of Borrower’s assets except in the ordinary
course of its business.

        SECTION 5.6.    GUARANTIES. Guarantee or become liable in any way as
surety, endorser (other than as endorser of negotiable instruments for deposit
or collection in the ordinary course of business), accommodation endorser or
otherwise for, nor pledge or hypothecate any assets of Borrower as security for,
any liabilities or obligations of any other person or entity in an amount in
excess of $250,000, except any of the foregoing in favor of Bank.

        SECTION 5.7.    LOANS, ADVANCES, INVESTMENTS. Make any loans or advances
to or investments in any person or entity that is otherwise permitted under
applicable law, in an amount not in excess of $250,000, except any of the
foregoing existing as of, and disclosed to Bank prior to, the date hereof.

        SECTION 5.8.    DIVIDENDS, DISTRIBUTIONS. Declare or pay any dividend or
distribution either in cash, stock or any other property on Borrower’s stock now
or hereafter outstanding, nor redeem, retire, repurchase or otherwise acquire
any shares of any class of Borrower’s stock now or hereafter outstanding.

        SECTION 5.9.    DISTRIBUTIONS. Declare or pay any distributions to its
members either in cash or any other property, nor redeem, retire, repurchase or
otherwise acquire any membership interest in Borrower.

        SECTION 5.10.    PLEDGE OF ASSETS. Mortgage, pledge, grant or permit to
exist a security interest in, or lien upon, all or any portion of Borrower’s
assets now owned or hereafter acquired, except any of the foregoing in favor of
Bank or which is existing as of, and disclosed to Bank in writing prior to, the
date hereof, other than security interests or liens granted for purposes of
securing purchase money indebtedness otherwise permitted under the terms of this
Agreement.

ARTICLE VI
EVENTS OF DEFAULT

        SECTION 6.1.    The occurrence of any of the following shall constitute
an “Event of Default” under this Agreement:

        (a)     Borrower shall fail to pay when due any principal, interest,
fees or other amounts payable under any of the Loan Documents.

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        (b)     Any financial statement or certificate furnished to Bank in
connection with, or any representation or warranty made by Borrower or any other
party under this Agreement or any other Loan Document shall prove to be
incorrect, false or misleading in any material respect when furnished or made.

        (c)     Any default in the performance of or compliance with any
obligation, agreement or other provision contained herein or in any other Loan
Document (other than those referred to in subsections (a) and (b) above), and
with respect to any such default which by its nature can be cured, such default
shall continue for a period of twenty (20) days from its occurrence.

        (d)     Any default in the payment or performance of any obligation, or
any defined event of default, under the terms of any contract or instrument
(other than any of the Loan Documents) pursuant to which Borrower, any guarantor
hereunder or any general partner or joint venturer in Borrower if a partnership
or joint venture (with each such guarantor, general partner and/or joint
venturer referred to herein as a “Third Party Obligor”) has incurred any debt or
other liability to any person or entity, including Bank.

        (e)     The filing of a notice of judgment lien against Borrower or any
Third Party Obligor in an amount in excess of $500,000; or the recording of any
abstract of judgment against Borrower or any Third Party Obligor in any county
in which Borrower or such Third Party Obligor has an interest in real property
in an amount in excess of $500,000; or the service of a notice of levy and/or of
a writ of attachment or execution, or other like process, against the assets of
Borrower or any Third Party Obligor in an amount in excess of $500,000; or the
entry of a judgment against Borrower or any Third Party Obligor in an amount in
excess of $500,000.

        (f)     Borrower or any Third Party Obligor shall become insolvent, or
shall suffer or consent to or apply for the appointment of a receiver, trustee,
custodian or liquidator of itself or any of its property, or shall generally
fail to pay its debts as they become due, or shall make a general assignment for
the benefit of creditors; Borrower or any Third Party Obligor shall file a
voluntary petition in bankruptcy, or seeking reorganization, in order to effect
a plan or other arrangement with creditors or any other relief under the
Bankruptcy Reform Act, Title 11 of the United States Code, as amended or
recodified from time to time (“Bankruptcy Code”), or under any state or federal
law granting relief to debtors, whether now or hereafter in effect; or any
involuntary petition or proceeding pursuant to the Bankruptcy Code or any other
applicable state or federal law relating to bankruptcy, reorganization or other
relief for debtors is filed or commenced against Borrower or any Third Party
Obligor, or Borrower or any Third Party Obligor shall file an answer admitting
the jurisdiction of the court and the material allegations of any involuntary
petition; or Borrower or any Third Party Obligor shall be adjudicated a
bankrupt, or an order for relief shall be entered against Borrower or any Third
Party Obligor by any court of competent jurisdiction under the Bankruptcy Code
or any other applicable state or federal law relating to bankruptcy,
reorganization or other relief for debtors.

        (h)     The death or incapacity of Borrower or any Third Party Obligor
if an individual. The dissolution or liquidation of Borrower or any Third Party
Obligor if a corporation, partnership, joint venture or other type of entity; or
Borrower or any such Third Party Obligor, or any of its directors, stockholders
or members, shall take action seeking to effect the dissolution or liquidation
of Borrower or such Third Party Obligor.

        (i)     Any change in ownership of an aggregate of fifty percent (50%)
or more of the common stock of equity in Borrower.

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        SECTION 6.2.    REMEDIES. Upon the occurrence of any Event of Default:
(a) all indebtedness of Borrower under each of the Loan Documents, any term
thereof to the contrary notwithstanding, shall at Bank’s option and without
notice become immediately due and payable without presentment, demand, protest
or notice of dishonor, all of which are hereby expressly waived by Borrower;
(b) the obligation, if any, of Bank to extend any further credit under any of
the Loan Documents shall immediately cease and terminate; and (c) Bank shall
have all rights, powers and remedies available under each of the Loan Documents,
or accorded by law, including without limitation the right to resort to any or
all security for any credit subject hereto and to exercise any or all of the
rights of a beneficiary or secured party pursuant to applicable law. All rights,
powers and remedies of Bank may be exercised at any time by Bank and from time
to time after the occurrence of an Event of Default, are cumulative and not
exclusive, and shall be in addition to any other rights, powers or remedies
provided by law or equity.

ARTICLE VII
MISCELLANEOUS

        SECTION 7.1.    NO WAIVER. No delay, failure or discontinuance of Bank
in exercising any right, power or remedy under any of the Loan Documents shall
affect or operate as a waiver of such right, power or remedy; nor shall any
single or partial exercise of any such right, power or remedy preclude, waive or
otherwise affect any other or further exercise thereof or the exercise of any
other right, power or remedy. Any waiver, permit, consent or approval of any
kind by Bank of any breach of or default under any of the Loan Documents must be
in writing and shall be effective only to the extent set forth in such writing.

        SECTION 7.2.    NOTICES. All notices, requests and demands which any
party is required or may desire to give to any other party under any provision
of this Agreement must be in writing delivered to each party at the following
address:

  BORROWER: ORION ENERGY SYSTEMS, INC.
1204 PILGRIM ROAD
PLYMOUTH, WISCONSIN 53073

  BORROWER: GREAT LAKES ENERGY TECHNOLOGIES, LLC
2001 MIRRO DRIVE
MANITOWOC, WI 54220

  BANK: WELLS FARGO BANK, NATIONAL ASSOCIATION
100 EAST WISCONSIN AVENUE, SUITE#1400
MILWAUKEE, WI 53202

or to such other address as any party may designate by written notice to all
other parties. Each such notice, request and demand shall be deemed given or
made as follows: (a) if sent by hand delivery, upon delivery; (b) if sent by
mail, upon the earlier of the date of receipt or three (3) days after deposit in
the U.S. mail, first class and postage prepaid; and (c) if sent by telecopy,
upon receipt.

        SECTION 7.3.    COSTS, EXPENSES AND ATTORNEYS’ FEES. Borrower shall pay
to Bank immediately upon demand the full amount of all payments, advances,
charges, costs and expenses, including reasonable attorneys’ fees (to include
outside counsel fees and all allocated costs of Bank’s in-house counsel),
expended or incurred by Bank in connection with (a) the negotiation and
preparation of this Agreement and the other Loan Documents, Bank’s continued
administration hereof and thereof, and the preparation of any amendments and
waivers hereto and thereto, (b) the enforcement of Bank’s rights and/or the
collection of any amounts which become due to Bank under any of the Loan
Documents, and (c) the prosecution or defense of any action in any way related
to any of the Loan Documents, including without limitation, any action for
declaratory relief, whether incurred at the trial or appellate level, in an
arbitration proceeding or otherwise, and including any of the foregoing incurred
in connection with any bankruptcy proceeding (including without limitation, any
adversary proceeding, contested matter or motion brought by Bank or any other
person) relating to Borrower or any other person or entity.

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        SECTION 7.4.    SUCCESSORS, ASSIGNMENT. This Agreement shall be binding
upon and inure to the benefit of the heirs, executors, administrators, legal
representatives, successors and assigns of the parties; provided however, that
Borrower may not assign or transfer its interests or rights hereunder without
Bank’s prior written consent. Bank reserves the right to sell, assign, transfer,
negotiate or grant participations in all or any part of, or any interest in,
Bank’s rights and benefits under each of the Loan Documents. In connection
therewith, Bank may disclose all documents and information which Bank now has or
may hereafter acquire relating to any credit subject hereto, Borrower or its
business, or any collateral required hereunder.

        SECTION 7.5.    ENTIRE AGREEMENT; AMENDMENT. This Agreement and the
other Loan Documents constitute the entire agreement between Borrower and Bank
with respect to each credit subject hereto and supersede all prior negotiations,
communications, discussions and correspondence concerning the subject matter
hereof. This Agreement may be amended or modified only in writing signed by each
party hereto.

        SECTION 7.6.    NO THIRD PARTY BENEFICIARIES. This Agreement is made and
entered into for the sole protection and benefit of the parties hereto and their
respective permitted successors and assigns, and no other person or entity shall
be a third party beneficiary of, or have any direct or indirect cause of action
or claim in connection with, this Agreement or any other of the Loan Documents
to which it is not a party.

        SECTION 7.7.    TIME. Time is of the essence of each and every provision
of this Agreement and each other of the Loan Documents.

        SECTION 7.8.    SEVERABILITY OF PROVISIONS. If any provision of this
Agreement shall be prohibited by or invalid under applicable law, such provision
shall be ineffective only to the extent of such prohibition or invalidity
without invalidating the remainder of such provision or any remaining provisions
of this Agreement.

        SECTION 7.9.    COUNTERPARTS. This Agreement may be executed in any
number of counterparts, each of which when executed and delivered shall be
deemed to be an original, and all of which when taken together shall constitute
one and the same Agreement.

        SECTION 7.10.    GOVERNING LAW. This Agreement shall be governed by and
construed in accordance with the laws of the State of Wisconsin.

        SECTION 7.11.    BUSINESS PURPOSE. Borrower represents and warrants that
each credit subject hereto is for a business, commercial, investment, or other
similar purpose and not primarily for a personal, family or household use.

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        SECTION 7.12.    ARBITRATION.

        (a)    Arbitration. The parties hereto agree, upon demand by any party,
to submit to binding arbitration all claims, disputes and controversies between
or among them (and their respective employees, officers, directors, attorneys,
and other agents), whether in tort, contract or otherwise in any way arising out
of or relating to (i) any credit subject hereto, or any of the Loan Documents,
and their negotiation, execution, collateralization, administration, repayment,
modification, extension, substitution, formation, inducement, enforcement,
default or termination; or (ii) requests for additional credit.

        (b)    Governing Rules. Any arbitration proceeding will (i) proceed in a
location in Wisconsin selected by the American Arbitration Association (“AAA”);
(ii) be governed by the Federal Arbitration Act (Title 9 of the United States
Code), notwithstanding any conflicting choice of law provision in any of the
documents between the parties; and (iii) be conducted by the AAA, or such other
administrator as the parties shall mutually agree upon, in accordance with the
AAA’s commercial dispute resolution procedures, unless the claim or counterclaim
is at least $1,000,000.00 exclusive of claimed interest, arbitration fees and
costs in which case the arbitration shall be conducted in accordance with the
AAA’s optional procedures for large, complex commercial disputes (the commercial
dispute resolution procedures or the optional procedures for large, complex
commercial disputes to be referred to herein as applicable, as the “Rules”). If
there is any inconsistency between the terms hereof and the Rules, the terms and
procedures set forth herein shall control. Any party who fails or refuses to
submit to arbitration following a demand by any other party shall bear all costs
and expenses incurred by such other party in compelling arbitration of any
dispute. Nothing contained herein shall be deemed to be a waiver by any party
that is a bank of the protections afforded to it under 12 U.S.C. §91 or any
similar applicable state law.

        (c)    No Waiver of Provisional Remedies, Self-Help and Foreclosure. The
arbitration requirement does not limit the right of any party to (i) foreclose
against real or personal property collateral; (ii) exercise self-help remedies
relating to collateral or proceeds of collateral such as setoff or repossession;
or (iii) obtain provisional or ancillary remedies such as replevin, injunctive
relief, attachment or the appointment of a receiver, before during or after the
pendency of any arbitration proceeding. This exclusion does not constitute a
waiver of the right or obligation of any party to submit any dispute to
arbitration or reference hereunder, including those arising from the exercise of
the actions detailed in sections (i), (ii) and (iii) of this paragraph.

        (d)    Arbitrator Qualifications and Powers. Any arbitration proceeding
in which the amount in controversy is $5,000,000.00 or less will be decided by a
single arbitrator selected according to the Rules, and who shall not render an
award of greater than $5,000,000.00. Any dispute in which the amount in
controversy exceeds $5,000,000.00 shall be decided by majority vote of a panel
of three arbitrators; provided however, that all three arbitrators must actively
participate in all hearings and deliberations. The arbitrator will be a neutral
attorney licensed in the State of Wisconsin or a neutral retired judge of the
state or federal judiciary of Wisconsin, in either case with a minimum of ten
years experience in the substantive law applicable to the subject matter of the
dispute to be arbitrated. The arbitrator will determine whether or not an issue
is arbitratable and will give effect to the statutes of limitation in
determining any claim. In any arbitration proceeding the arbitrator will decide
(by documents only or with a hearing at the arbitrator’s discretion) any
pre-hearing motions which are similar to motions to dismiss for failure to state
a claim or motions for summary adjudication. The arbitrator shall resolve all
disputes in accordance with the substantive law of Wisconsin and may grant any
remedy or relief that a court of such state could order or grant within the
scope hereof and such ancillary relief as is necessary to make effective any
award. The arbitrator shall also have the power to award recovery of all costs
and fees, to impose sanctions and to take such other action as the arbitrator
deems necessary to the same extent a judge could pursuant to the Federal Rules
of Civil Procedure, the Wisconsin Rules of Civil Procedure or other applicable
law. Judgment upon the award rendered by the arbitrator may be entered in any
court having jurisdiction. The institution and maintenance of an action for
judicial relief or pursuit of a provisional or ancillary remedy shall not
constitute a waiver of the right of any party, including the plaintiff, to
submit the controversy or claim to arbitration if any other party contests such
action for judicial relief.

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        (e)    Discovery. In any arbitration proceeding, discovery will be
permitted in accordance with the Rules. All discovery shall be expressly limited
to matters directly relevant to the dispute being arbitrated and must be
completed no later than 20 days before the hearing date. Any requests for an
extension of the discovery periods, or any discovery disputes, will be subject
to final determination by the arbitrator upon a showing that the request for
discovery is essential for the party’s presentation and that no alternative
means for obtaining information is available.

        (f)    Class Proceedings and Consolidations. No party hereto shall be
entitled to join or consolidate disputes by or against others in any
arbitration, except parties who have executed any Loan Document, or to include
in any arbitration any dispute as a representative or member of a class, or to
act in any arbitration in the interest of the general public or in a private
attorney general capacity.

        (g)    Payment Of Arbitration Costs And Fees. The arbitrator shall award
all costs and expenses of the arbitration proceeding.

        (h)    Miscellaneous. To the maximum extent practicable, the AAA, the
arbitrators and the parties shall take all action required to conclude any
arbitration proceeding within 180 days of the filing of the dispute with the
AAA. No arbitrator or other party to an arbitration proceeding may disclose the
existence, content or results thereof, except for disclosures of information by
a party required in the ordinary course of its business or by applicable law or
regulation. If more than one agreement for arbitration by or between the parties
potentially applies to a dispute, the arbitration provision most directly
related to the Loan Documents or the subject matter of the dispute shall
control. This arbitration provision shall survive termination, amendment or
expiration of any of the Loan Documents or any relationship between the parties.

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        IN WITNESS WHEREOF, the parties hereto have caused this Agreement to be
executed as of the day and year first written above.

WELLS FARGO BANK, ORION ENERGY SYSTEMS, INC NATIONAL ASSOCIATION
By:  /s/ Neal R. Verfuerth By:  /s/ Thomas J. Fameree         Neal R. Verfuerth,
President/         Thomas J. Fameree         Chief Executive Officer
        Vice President
GREAT LAKES ENERGY TECHNOLOGIES, LLC
By:  /s/ Neal R. Verfuerth         Neal R. Verfuerth         Manager

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