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                                                                   EXHIBIT 10.31

                              COMMON STOCK WARRANT

THE SECURITIES REPRESENTED BY THIS CERTIFICATE HAVE NOT BEEN REGISTERED,
QUALIFIED, APPROVED OR DISAPPROVED UNDER THE SECURITIES ACT OF 1933, AS AMENDED,
OR THE SECURITIES LAWS OF ANY STATE AND MAY NOT BE SOLD OR OTHERWISE DISPOSED OF
EXCEPT PURSUANT TO AN EFFECTIVE REGISTRATION STATEMENT UNDER SUCH ACT AND
APPLICABLE STATE SECURITIES LAWS OR AN APPLICABLE EXEMPTION FROM THE
REGISTRATION REQUIREMENTS OF SUCH ACT OR SUCH LAWS AND NEITHER THE UNITED STATES
SECURITIES AND EXCHANGE COMMISSION NOR ANY OTHER FEDERAL OR STATE REGULATORY
AUTHORITY HAS PASSED ON OR ENDORSED THE MERITS OF THESE SECURITIES.

THE SHARES OF COMMON STOCK ISSUABLE UPON THE EXERCISE OF THE SECURITIES
REPRESENTED HEREBY ARE SUBJECT TO AN INVESTOR RIGHTS AGREEMENT, A STOCKHOLDERS
AGREEMENT AND A STOCK TRADING AGREEMENT, AS EACH OF THE SAME MAY BE AMENDED FROM
TIME TO TIME, COPIES OF WHICH ARE AVAILABLE FOR INSPECTION AT THE PRINCIPAL
OFFICES OF THE COMPANY.

                                                                  WARRANT NO. 21
                                                                              --

                               WARRANT CERTIFICATE

                       TO PURCHASE SHARES OF COMMON STOCK,

                           PAR VALUE $0.0001 PER SHARE

                                       OF

                               ELECTRIC CITY CORP.

          THIS IS TO CERTIFY THAT EP Power Finance, L.L.C. or its registered
assigns (the "HOLDER"), is the owner of 750,000 warrants (the "WARRANTS"), each
of which entitles the registered Holder thereof to purchase from Electric City
Corp., a Delaware corporation (the "COMPANY"), one fully paid, duly authorized
and nonassessable share of Common Stock, par value $0.0001 per share (the
"COMMON STOCK"), of the Company at any time or from time to time after sixty
(60) days from the Issue Date (as defined in SECTION 2(a)), but on or before
5:00 p.m., New York City time, on the Warrant Expiration Date, at an exercise
price of $1.00 per share, subject to adjustment from time to time as set forth
herein (the "EXERCISE PRICE"), all on the terms and subject to the conditions
hereinafter set forth.

          The number of shares of Common Stock issuable upon exercise of each
Warrant (the "NUMBER ISSUABLE") shall be determined for each Warrant by dividing
$1.00 by the Exercise Price in effect at the time of such exercise, and is
initially one (1) share of Common Stock.

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Capitalized terms used herein but not otherwise defined shall have the meanings
given them in SECTION 13 hereof or, if not therein defined, in the Securities
Purchase Agreement.

          Section 1. EXERCISE OF WARRANTS. Subject to the last paragraph of this
SECTION 1, the Warrants evidenced hereby may be exercised, in whole or in part,
by the registered Holder hereof at any time or from time to time after sixty
(60) days from the Issue Date, but on or before 5:00 p.m., New York City time,
on the Warrant Expiration Date, upon delivery to the Company at the principal
executive office of the Company in the United States of America, of (a) this
Warrant Certificate, (b) a written notice stating that such Holder elects to
exercise the Warrants evidenced hereby in accordance with the provisions of this
SECTION 1 and specifying the number of Warrants being exercised and the name or
names in which such Holder wishes the certificate or certificates for shares of
Common Stock to be issued and (c) payment of the Exercise Price for the shares
of Common Stock issuable upon exercise of such Warrants, which shall be payable
by any one or any combination of the following: (i) cash, (ii) certified or
official bank check payable to the order of the Company, (iii) by the surrender
(which surrender shall be evidenced by cancellation of the relevant number of
Warrants represented by any Warrant certificate presented in connection with a
Cashless Exercise (as defined below)) of a Warrant or Warrants (represented by
one or more relevant Warrant certificates), and without the payment of the
Exercise Price in cash, in return for the delivery to the surrendering Holder of
such number of shares of Common Stock equal to the number of shares of Common
Stock for which such Warrant is exercised as of the date of exercise (if the
Exercise Price were being paid in cash) reduced by that number of shares of
Common Stock equal to the number of shares for which such Warrant is exercised
multiplied by a fraction, the numerator of which is (A) the Exercise Price and
the denominator of which is (B) the Market Price of one share of Common Stock on
the Business Day that immediately precedes the day of exercise of the Warrant or
(iv) by the delivery of shares of Common Stock that are valued at the Market
Price on the Business Day immediately preceding the day of the exercise of the
Warrant that are either held by the Holder or are acquired in connection with
such exercise, and without payment of the Exercise Price in cash. Any share of
Common Stock delivered as payment of the Exercise Price in connection with an
In-Kind Exercise (as defined below) shall be deemed to have a value equal to the
Market Price of one share of Common Stock on the Business Day that immediately
precedes the day of exercise of the Warrant. An exercise of a Warrant in
accordance with clause (iii) is herein referred to as a "CASHLESS EXERCISE" and
an exercise of a Warrant in accordance with clause (iv) is herein referred to as
an "IN-KIND EXERCISE." The documentation and consideration, if any, delivered in
accordance with clauses (a), (b) and (c) of this paragraph above are
collectively referred to herein as the "WARRANT EXERCISE DOCUMENTATION." For the
purposes of this SECTION 1, Market Price shall be calculated without reference
to the last sentence of the definition thereof.

          As promptly as practicable, and in any event within two (2) Business
Days after receipt of the Warrant Exercise Documentation, the Company shall
deliver or cause to be delivered certificates representing the number of validly
issued, fully paid and nonassessable shares of Common Stock issuable in
connection with such exercise, and if less than the full number of Warrants
evidenced hereby are being exercised, a new Warrant Certificate or Certificates,
of like tenor, for the number of Warrants evidenced by this Warrant Certificate,
less the number of Warrants then being exercised or surrendered; PROVIDED,
HOWEVER, that no new Warrant Certificate need be delivered if the Warrant
Expiration Date has occurred. Such exercise shall be deemed to have been made at
the close of business on the date of delivery of the


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Warrant Exercise Documentation so that the Person entitled to receive shares of
Common Stock upon such exercise shall be treated for all purposes as having
become the record holder of such shares of Common Stock at such time.

          The Company shall pay all expenses in connection with, and all taxes
and other governmental charges (other than income taxes of the Holder) that may
be imposed in respect of the issue or delivery of any shares of Common Stock
issuable upon the exercise of the Warrants evidenced hereby. The Company shall
not be required, however, to pay any tax or other charge imposed in connection
with any transfer involved in the issue of any certificate for shares of Common
Stock in any name other than that of the registered Holder of the Warrants
evidenced hereby.

          In connection with the exercise of any Warrants evidenced hereby, at
the Company's option, no fractions of shares of Common Stock shall be issued,
but in lieu thereof the Company may elect to pay a cash adjustment in respect of
such fractional interest in an amount equal to any such fractional interest
multiplied by the current Market Price per share of Common Stock on the Business
Day that precedes the day of exercise. If more than one such Warrant shall be
exercised by the Holder thereof at the same time, the number of full shares of
Common Stock issuable on such exercise shall be computed on the basis of the
total number of Warrants so exercised.

          SECTION 2. ADJUSTMENTS. The Exercise Price shall be subject to
adjustment from time to time as provided in this SECTION 2.

          (a)  ADJUSTMENT OF EXERCISE PRICE UPON ISSUANCE OF COMMON STOCK. If
after August 31, 2001 (the "ISSUE DATE") the Company shall issue or sell any
shares of its Common Stock (except upon exercise of the Warrants and shares
issued as a result of adjustments made under the terms of the Warrants) for a
price per share less than (including, without limitation, those circumstances
described in paragraphs (i) through (vii) below), the Exercise Price in effect
on the date immediately prior to the date of such issue or sale, then,
immediately upon such issue or sale, the Exercise Price then in effect shall be
reduced to such lower price per share.

               (i)  ISSUANCE OF RIGHTS OR OPTIONS. In case at any time after the
Issue Date the Company shall in any manner grant (whether directly or by
assumption in a merger or otherwise), any rights to subscribe for or to
purchase, or any options or warrants for the purchase of, Common Stock or any
stock, notes or securities convertible into or exchangeable for Common Stock
(such convertible or exchangeable stock, notes or securities being herein called
"CONVERTIBLE SECURITIES"), whether or not such rights, options or warrants or
the right to convert or exchange any such Convertible Securities are immediately
exercisable, such grant shall be deemed a sale by the Company of its Common
Stock and the price per share for such deemed sale of Common Stock shall be
determined by dividing (A) the total amount, if any, in cash or in property
received or receivable by the Company as consideration for the granting of such
rights, options or warrants, plus the minimum aggregate amount of additional
consideration, if any, payable to the Company upon the exercise of such rights,
options or warrants, plus, in the case of such rights, options or warrants that
relate to Convertible Securities, the minimum aggregate amount of additional
consideration, if any, payable upon the issue or sale of such Convertible
Securities and upon the conversion or exchange thereof, by (B)


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the total maximum number of shares of Common Stock issuable upon the exercise of
such rights, options or warrants or upon the conversion or exchange of all such
Convertible Securities issuable upon the exercise of such rights, options or
warrants. Except as provided in SECTION 2(a)(iii), no further adjustment of the
Exercise Price shall be made upon the actual issue of such Common Stock or of
such Convertible Securities upon exercise of such rights, options or warrants or
upon the actual issue of such Common Stock upon conversion or exchange of such
Convertible Securities.

               (ii) ISSUANCE OF CONVERTIBLE SECURITIES. In case at any time
after the Issue Date the Company shall in any manner issue (whether directly or
by assumption in a merger or otherwise) or sell any Convertible Securities,
whether or not the rights to exchange or convert thereunder are immediately
exercisable, such issuance or sale of Convertible Securities shall be deemed a
sale by the Company of its Common Stock and the price per share for such Common
Stock shall be determined by dividing (A) the total amount received or
receivable in cash or in property by the Company as consideration for the issue
or sale of such Convertible Securities, plus the minimum aggregate amount of
additional consideration, if any, payable to the Company upon the conversion or
exchange thereof, by (B) the total maximum number of shares of Common Stock
issuable upon the conversion or exchange of all such Convertible Securities;
PROVIDED, HOWEVER, that (I) except as otherwise provided in SECTION 2(a)(iii),
no further adjustment of the Exercise Price shall be made upon the actual issue
of such Common Stock upon conversion or exchange of such Convertible Securities,
and (II) if any such issue or sale of such Convertible Securities is made upon
exercise of any rights to subscribe for or to purchase or any option to purchase
any such Convertible Securities for which adjustments of the Exercise Price have
been or are to be made pursuant to other provisions of this SECTION 2(a), no
further adjustment of the Exercise Price shall be made by reason of such issue
or sale.

               (iii) CHANGE IN OPTION PRICE OR EXERCISE PRICE. If the purchase
price provided for in any right or option referred to in SECTION 2(a)(i), the
additional consideration, if any, payable upon the conversion or exchange of any
Convertible Securities referred to in SECTION 2(a)(i) or 2(a)(ii), or the rate
at which any Convertible Securities referred to in SECTION 2(a)(i) or 2(a)(ii)
are convertible into or exchangeable for Common Stock shall change (other than
under or by reason of provisions designed to protect against dilution), the
Exercise Price then in effect hereunder shall forthwith be readjusted (increased
or decreased, as the case may be) to the Exercise Price that would have been in
effect at such time had such rights, options or Convertible Securities still
outstanding provided for such changed purchase price, additional consideration
or conversion rate, as the case may be, at the time initially granted, issued or
sold. No readjustment pursuant to the preceding sentence shall have the effect
of increasing the Exercise Price by an amount in excess of the amount of the
adjustment thereof originally made in respect of the issue, sale, grant or
assumption of rights, options or Convertible Securities. On the expiration of
any such option or right referred to in SECTION 2(a)(i) or the termination of
any such right to convert or exchange any such Convertible Securities referred
to in SECTION 2(a)(i) or 2(a)(ii), the Exercise Price then in effect hereunder
shall forthwith be readjusted (increased or decreased, as the case may be) to
the Exercise Price that would have been in effect at the time of such expiration
or termination had such right, option or Convertible Securities, to the extent
outstanding immediately prior to such expiration or termination, never been
granted, issued or sold. If the purchase price provided for in any such right or
option referred to in SECTION 2(a)(i) or the rate at which any Convertible
Securities


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referred to in SECTION 2(a)(ii) are convertible into or exchangeable for Common
Stock shall be reduced at any time under or by reason of provisions with respect
thereto designed to protect against dilution, then in case of the delivery of
shares of Common Stock upon the exercise of any such right or option or upon
conversion or exchange of any such Convertible Securities, the Exercise Price
then in effect hereunder shall, if not already adjusted, forthwith be adjusted
to such amount as would have obtained had such right, option or Convertible
Securities never been issued as to such shares of Common Stock and had
adjustments been made upon the issuance of the shares of Common Stock delivered
as aforesaid, but only if as a result of such adjustment the Exercise Price then
in effect hereunder is thereby reduced.

               (iv) CONSIDERATION FOR STOCK. Anything herein to the contrary
notwithstanding, in case at any time any shares of Common Stock or Convertible
Securities or any rights, options or warrants to purchase any such Common Stock
or Convertible Securities shall be issued or sold for cash, the consideration
received therefor shall be deemed to be the amount received by the Company
therefor, without deduction therefrom of any expenses incurred or any
underwriting commissions or concessions paid or allowed by the Company in
connection therewith.

               In case at any time any shares of Common Stock or Convertible
Securities or any rights or options to purchase any such shares of Common Stock
or Convertible Securities shall be issued or sold for a consideration other than
cash, in whole or in part, the amount of the consideration other than cash
received by the Company shall be deemed to be the fair value of such
consideration as determined reasonably and in good faith by the Board of
Directors of the Company, without deduction of any expenses incurred or any
underwriting commissions or concessions paid or allowed by the Company in
connection therewith. In case at any time any shares of Common Stock or
Convertible Securities or any rights or options to purchase such shares of
Common Stock or Convertible Securities shall be issued in connection with any
merger or consolidation in which the Company is the surviving company, the
amount of consideration received therefor shall be deemed to be the fair value
as determined reasonably and in good faith by the Board of Directors of the
Company of such portion of the assets and business of the nonsurviving
corporation as the Board may determine to be attributable to such shares of
Common Stock, Convertible Securities, rights or options, as the case may be. In
case at any time any rights or options to purchase any shares of Common Stock or
Convertible Securities shall be issued in connection with the issue and sale of
other securities of the Company, together comprising one integral transaction in
which no consideration is allocated to such rights or options by the parties
thereto, such rights or options shall be deemed to have been issued for an
amount of consideration equal to the fair value thereof as determined reasonably
and in good faith by the Board of Directors of the Company.

               (v)  RECORD DATE. In case the Company shall take a record of the
holders of its Common Stock for the purpose of entitling them to subscribe for
or purchase shares of Common Stock or Convertible Securities, then such record
date shall be deemed to be the date of the issue or sale of the shares of Common
Stock deemed to have been issued or sold as a result of the granting of such
right of subscription or purchase.

               (vi) ADJUSTMENT TO DETERMINATION OF EXERCISE PRICE. When making
the calculations and determinations described in this SECTION 2(a), there shall
not be taken into


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account (A) the issuance of Common Stock upon the exercise of options or
warrants outstanding on the Issue Date, (B) the issuance of Common Stock upon
the conversion of the Series A Preferred Stock of the Company, (C) the issuance
of Common Stock upon exercise of the Warrants evidenced by this Warrant
Certificate, any other warrants to purchase Common Stock issued pursuant to the
Securities Purchase Agreement, or the Placement Agent Warrants (as defined in
the Securities Purchase Agreement), (D) the issuance of Series A Preferred Stock
upon exercise of the Series A Preferred Stock Warrants (as defined in the
Securities Purchase Agreement) issued pursuant to the Securities Purchase
Agreement Agreement or the Additional Purchase Agreement and (E) the issuance of
320,868 shares of Common Stock pursuant to the Securities Purchase Agreement.

               (vii) GOOD FAITH. If any event occurs as to which in the
reasonable opinion of the Board of Directors of the Company, in good faith, the
other provisions of this SECTION 2 are not strictly applicable but the lack of
any adjustment in the Exercise Price or the Number Issuable or both would not in
the opinion of the Board of Directors of the Company fairly protect the exercise
rights of the Holder, in accordance with the basic intent and principles of such
provisions, then the Board of Directors of the Company shall appoint a firm of
independent certified public accountants (which may be the regular auditors of
the Company) of recognized national standing, which shall give their opinion
upon the adjustment, if any, to the Exercise Price or Number Issuable or both,
as the case may be, on a basis consistent with the basic intent and principles
of this SECTION 2, necessary to preserve, without dilution, the exercise rights
of all the registered Holders of the Warrants in accordance with this Warrant
Certificate.

               (viii) NOTICE OF CHANGE IN EXERCISE PRICE. The Company promptly
shall deliver to each registered Holder of Warrants at least five (5) Business
Days prior to effecting any transaction that would result in an increase or
decrease in the Exercise Price pursuant to this SECTION 2, a statement, signed
by its independent certified public accountants, setting forth in reasonable
detail the event requiring the adjustment and the method by which such
adjustment was calculated and specifying the increased or decreased Exercise
Price then in effect following such adjustment.

          (b)  SUBDIVISION; COMBINATION OF STOCK OR STOCK DIVIDENDS. In case the
Company shall at any time subdivide its outstanding shares of Common Stock into
a greater number of shares, by split or otherwise, or issue additional shares of
Common Stock as a dividend (other than a dividend in accordance with Section 3
of the Certificate of Designations (as defined in the Securities Purchase
Agreement) in respect of the Series A Preferred Stock), or make any other
distribution upon any class or series of stock payable in shares of Common Stock
or Convertible Securities, the Exercise Price in effect immediately prior to
such subdivision shall be proportionately reduced and, conversely, in case the
outstanding shares of Common Stock of the Company shall be combined into a
smaller number of shares, the Exercise Price in effect immediately prior to such
combination shall be proportionately increased.

          (c)  REORGANIZATION; RECLASSIFICATION; CONSOLIDATION; MERGER OR SALE
OF ASSETS. In case of (i) any capital reorganization or reclassification or
other change of outstanding shares of Common Stock (other than a change in par
value, or from par value to no par value, or from no par value to par value, or
as a result of a subdivision or combination), (ii) any consolidation


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or merger of the Company with or into another Person (other than a consolidation
or merger in which the Company is the resulting or surviving Person and that
does not result in any reclassification or change of outstanding Common Stock)
or (iii) transfer or sale of all or substantially all of the Company's Assets to
another person (any of the foregoing, a "TRANSACTION"), the Company, or such
successor or purchasing Person, as the case may be, shall execute and deliver to
each Holder of the Warrants evidenced hereby, at least five (5) Business Days
prior to effecting any of the foregoing Transactions, a certificate that the
Holder of each such Warrant then outstanding shall have the right thereafter to
exercise such Warrant into the kind and highest amount of shares of stock or
other securities (of the Company or another issuer) or property or cash
receivable upon such Transaction by a holder of the number of shares of Common
Stock into which such Warrant could have been exercised immediately prior to
such Transaction. Such certificate shall provide for adjustments that shall be
as nearly equivalent as may be practicable to the adjustments provided for in
this SECTION 2 and shall contain other terms identical to the terms hereof. If,
in the case of any such Transaction, the stock, other securities, cash or
property receivable thereupon by a holder of Common Stock includes shares of
stock or other securities of a Person other than the successor or purchasing
Persons and other than the Company, who controls or is controlled by the
successor or purchasing Person or who, in connection with such Transaction,
issues stock, securities, other property or cash to holders of Common Stock,
then such certificate also shall be executed by such Person, and such Person
shall, in such certificate, specifically assume the obligations of such
successor or purchasing Person and acknowledge its obligations to issue such
stock, securities, other property or cash to Holders of the Warrants upon
exercise thereof as provided above. The provisions of this SECTION 2(c)
similarly shall apply to successive Transactions.

          (d)  ADJUSTMENT FOR OTHER DISTRIBUTIONS. If the Company distributes to
all holders of its Common Stock any of its assets (including but not limited to
cash), debt securities, preferred stock, or any rights or warrants to purchase
debt securities, preferred stock, assets or other securities of the Company, the
Exercise Price shall be adjusted in accordance with the following formula:

                      E'   =   E   x   M   -   F
                                       ---------
                                           M

          where:

          E'   =   the adjusted Exercise Price.

          E    =   the current Exercise Price.

          M    =   the Market Price of one share of Common Stock on the
record date mentioned below.

          F    =   the fair market value (determined in good faith by
the Board of Directors of the Company) on the record date of the assets,
securities, rights or warrants applicable to one share of Common Stock.

          The adjustment shall be made successively whenever any such
distribution is made and shall become effective immediately after the record
date for the determination of


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stockholders entitled to receive the distribution. This SECTION 2(d) does not
apply to any dividend or distribution that results in an adjustment to the
Exercise Price pursuant to SECTION 2(a) or SECTION 2(b) above.

          SECTION 3. NOTICE OF CERTAIN EVENTS. In case at any time or from time
to time the Company shall declare any dividend or any other distribution to the
holders of its Common Stock, or shall authorize the granting to the holders of
its Common Stock of rights or warrants to subscribe for or purchase any
additional shares of stock of any class or any other right, or shall authorize
the issuance or sale of any other shares or rights that would result in an
adjustment to the Exercise Price pursuant to SECTION 2(a) or SECTION 2(d), or
there shall be any capital reorganization or reclassification of the Common
Stock or consolidation or merger of the Company with or into another Person, or
any sale or other disposition of all or substantially all the assets of the
Company, or there shall be a voluntary or involuntary dissolution, liquidation
or winding up of the Company, then, in any one or more of such cases the Company
shall mail to each Holder of the Warrants evidenced hereby at such Holder's
address as it appears on the transfer books of the Company, as promptly as
practicable but in any event at least ten (10) Business Days prior to the
applicable date hereinafter specified, a notice stating (a) the date on which a
record is to be taken for the purpose of such dividend, distribution, rights or
warrants or, if a record is not to be taken, the date as of which the holders of
Common Stock of record to be entitled to such dividend, distribution, rights or
warrants are to be determined, (b) the issue date of such dividend,
distribution, rights or warrants or (c) the date on which such reorganization,
reclassification, consolidation, merger, sale, disposition, dissolution,
liquidation or winding up is expected to become effective. Such notice also
shall specify the date as of which it is expected that the holders of Common
Stock of record shall be entitled to exchange their Common Stock for shares of
stock or other securities or property or cash deliverable upon such
reorganization, reclassification, consolidation, merger, sale, disposition,
dissolution, liquidation or winding up.

          SECTION 4. CERTAIN COVENANTS. The Company will at all times reserve
and keep available, free from preemptive rights, out of the aggregate of its
authorized but unissued Common Stock or its authorized and issued Common Stock
held as treasury stock, for the purpose of enabling it to satisfy any obligation
to issue Common Stock upon exercise of the Warrants, the maximum number of
shares of Common Stock that may then be deliverable upon the exercise of all
outstanding Warrants. The Company shall take all action required to increase the
authorized number of shares of Common Stock if at any time there shall be
insufficient authorized but unissued shares of Common Stock to permit such
reservation or to permit the exercise of all outstanding Warrants.

          The Company or, if appointed, the transfer agent for the Common Stock
(the "TRANSFER AGENT") and every subsequent transfer agent for any shares of the
Company's capital stock issuable upon the exercise of any of the rights of
purchase aforesaid will be irrevocably authorized and directed at all times to
reserve such number of authorized shares as shall be required for such purpose.
The Company will keep a copy of this Warrant Certificate on file with the
Transfer Agent and with every subsequent transfer agent for any shares of the
Company's capital stock issuable upon the exercise of the rights of purchase
represented by the Warrants. The Company will furnish such Transfer Agent a copy
of all notices of adjustments and certificates related thereto transmitted to
each Holder pursuant to SECTION 2(a)(viii) hereof.


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          Before taking any action that would cause an adjustment pursuant to
SECTION 2 hereof to reduce the Exercise Price below the then par value (if any)
of the Common Stock, the Company will take any corporate action that may, in the
opinion of its counsel (which may be counsel employed by the Company), be
necessary in order that the Company may validly and legally issue fully paid and
nonassessable Common Stock at the Exercise Price as so adjusted.

          The Company covenants that all Common Stock that may be issued upon
exercise of the Warrants will, upon issue, be validly issued, fully paid,
nonassessable, free of preemptive rights and free from all taxes, liens, charges
and security interests with respect to the issue thereof.

          SECTION 5. REGISTERED HOLDER. The person in whose name this Warrant
Certificate is registered shall be deemed the owner hereof and of the Warrants
evidenced hereby for all purposes.

          SECTION 6. TRANSFER OF WARRANTS. Any transfer of the rights
represented by this Warrant Certificate shall be effected by the surrender of
this Warrant Certificate, along with the form of assignment attached hereto,
properly completed and executed by the registered Holder hereof, at the
principal executive office of the Company in the United States of America.
Thereupon, the Company shall issue in the name or names specified by the
registered Holder hereof and, in the event of a partial transfer, in the name of
the registered Holder hereof, a new Warrant Certificate or Certificates
evidencing the right to purchase such number of shares of Common Stock as shall
be equal to the number of shares of Common Stock then purchasable hereunder.

          SECTION 7. RESTRICTIVE LEGEND. Each certificate representing the
Common Stock issued upon exercise of this Warrant shall be stamped or otherwise
imprinted with a legend in the following form (in addition to any legend
required under applicable state securities laws):

          THE SECURITIES REPRESENTED BY THIS CERTIFICATE HAVE NOT BEEN
          REGISTERED, QUALIFIED, APPROVED OR DISAPPROVED UNDER THE
          SECURITIES ACT OF 1933, AS AMENDED, OR THE SECURITIES LAWS
          OF ANY STATE AND MAY NOT BE SOLD OR OTHERWISE DISPOSED OF
          EXCEPT PURSUANT TO AN EFFECTIVE REGISTRATION STATEMENT UNDER
          SUCH ACT AND APPLICABLE STATE SECURITIES LAWS OR AN
          APPLICABLE EXEMPTION FROM THE REGISTRATION REQUIREMENTS OF
          SUCH ACT OR SUCH LAWS AND NEITHER THE UNITED STATES
          SECURITIES AND EXCHANGE COMMISSION NOR ANY OTHER FEDERAL OR
          STATE REGULATORY AUTHORITY HAS PASSED ON OR ENDORSED THE
          MERITS OF THESE SECURITIES.

          THE SECURITIES REPRESENTED HEREBY ARE SUBJECT TO AN INVESTOR
          RIGHTS AGREEMENT, A STOCKHOLDERS AGREEMENT AND A STOCK
          TRADING


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          AGREEMENT, AS EACH OF THE SAME MAY BE AMENDED FROM TIME TO
          TIME, COPIES OF WHICH ARE AVAILABLE FOR INSPECTION AT THE
          PRINCIPAL OFFICES OF THE COMPANY.

Said legends shall be removed by the Company, upon the request of the holder
thereof, at such time as the restrictions on the transfer of the applicable
security under applicable securities laws and the obligations imposed on the
holder thereof under the Investor Rights Agreement, the Stockholders Agreement
and the Stock Trading Agreement, as applicable, shall have terminated.

          SECTION 8. DENOMINATIONS. The Company will, at its expense, promptly
upon surrender of this Warrant Certificate at the principal executive office of
the Company in the United States of America, execute and deliver to the
registered Holder hereof a new Warrant Certificate or Certificates in
denominations specified by such Holder for an aggregate number of Warrants equal
to the number of Warrants evidenced by this Warrant Certificate.

          SECTION 9. REPLACEMENT OF WARRANTS. Upon receipt of evidence
satisfactory to the Company of the loss, theft, destruction or mutilation of
this Warrant Certificate and, in the case of loss, theft or destruction, upon
delivery of an indemnity reasonably satisfactory to the Company (in the case of
an insurance company or other institutional investor, its own unsecured
indemnity agreement shall be deemed to be reasonably satisfactory), or, in the
case of mutilation, upon surrender and cancellation thereof, the Company will
issue a new Warrant Certificate of like tenor for a number of Warrants equal to
the number of Warrants evidenced by this Warrant Certificate.

          SECTION 10. GOVERNING LAW. Except as to matters governed by the
General Corporation Law of the State of Delaware and decisions thereunder of the
Delaware courts applicable to Delaware corporations, which shall be governed by
such laws and decisions, this Warrant Certificate shall be construed and
enforced in accordance with, and the rights of the parties shall be governed by,
the laws of the State of New York applicable to agreements made and to be
performed entirely within such State.

          SECTION 11. RIGHTS INURE TO REGISTERED HOLDER. The Warrants evidenced
by this Warrant Certificate will inure to the benefit of and be binding upon the
registered Holder thereof and the Company and their respective successors and
permitted assigns. Nothing in this Warrant Certificate shall be construed to
give to any Person other than the Company and the registered Holder and their
respective successors and permitted assigns any legal or equitable right, remedy
or claim under this Warrant Certificate, and this Warrant Certificate shall be
for the sole and exclusive benefit of the Company and such registered Holder.
Nothing in this Warrant Certificate shall be construed to give the registered
Holder hereof any rights as a Holder of shares of Common Stock until such time,
if any, as the Warrants evidenced by this Warrant Certificate are exercised in
accordance with the provisions hereof.

          SECTION 12. NOTICE. All notices, demands and other communications
provided for or permitted hereunder shall be made in writing and shall be given
by registered or certified first-class mail, return receipt requested,
nationally recognized overnight delivery service or personal delivery, (a) if to
the Holder of a Warrant, at such Holder's last known address appearing on the
books of the Company; and (b) if to the Company, at its principal executive


                                       10
<Page>

office in the United States located at the address designated for notices in the
Securities Purchase Agreement, or such other address as shall have been
furnished to the party given or making such notice, demand or other
communication. All such notices and communications shall be deemed to have been
duly given: when delivered by hand, if personally delivered; when delivered if
delivered by a nationally recognized overnight delivery service; and five (5)
Business Days after being deposited in the mail, as aforesaid, postage prepaid,
if mailed.

          SECTION 13. DEFINITIONS. For the purposes of this Warrant Certificate,
the following terms shall have the meanings indicated below:

          "ADDITIONAL PURCHASE AGREEMENT" means the securities purchase
agreement providing for the issuance and sale of Series A Preferred Stock and
Series A Preferred Stock Warrants to the Additional Purchasers, as contemplated
by Section 2.3 of the Securities Purchase Agreement.

          "ADDITIONAL PURCHASER" shall mean each purchaser under the Additional
Purchase Agreement.

          "BUSINESS DAY" means any day other than a Saturday, Sunday or other
day on which commercial banks in the City of New York are authorized or required
by law or executive order to close.

          "CASHLESS EXERCISE" shall have the meaning set forth in SECTION 1
hereof.

          "COMPANY" shall have the meaning set forth in the preamble hereof.

          "COMMON STOCK" shall have the meaning set forth in the preamble
hereof.

          "CONVERTIBLE SECURITIES" shall have the meaning set forth in SECTION
2(a)(i) hereof.

          "EXERCISE PRICE" shall have the meaning set forth in the preamble
hereof.

          "HOLDER" shall have the meaning set forth in the preamble.

          "IN-KIND EXERCISE" shall have the meaning set forth in SECTION 1
hereof.

          "ISSUE DATE" shall have the meaning set forth in SECTION 2(a) hereof.

          "MARKET PRICE" means the last reported sale price of the applicable
security as reported by the American Stock Exchange or the National Association
of Securities Dealers, Inc. Automatic Quotations System or, if the applicable
security is listed or admitted for trading on another securities exchange, the
last reported sales price of the applicable security on the principal exchange
on which the applicable security is listed or admitted for trading (which shall
be for consolidated trading if applicable to such exchange), or if neither so
reported or listed or admitted for trading, the last reported bid price of the
applicable security in the over-the-counter market. In the event that the Market
Price cannot be determined as aforesaid, the Board of Directors of the Company
shall determine the Market Price on the basis of such quotations as it in good
faith considers appropriate, in consultation with a nationally recognized
investment bank. The Market


                                       11
<Page>

Price shall be such price averaged over a period of ten (10) consecutive
Business Days ending two (2) days prior to the day as of which "Market Price" is
being determined.

          "NUMBER ISSUABLE" shall have the meaning set forth in the preamble.

          "PERSON" means any individual, corporation, limited liability company,
partnership, trust, incorporated or unincorporated association, joint venture,
joint stock company, government (or an agency or political subdivision thereof)
or other entity of any kind.

          "SECURITIES PURCHASE AGREEMENT" means that certain Securities Purchase
Agreement, dated July 31, 2001, among the Company, the Holder and the other
parties signatory thereto, as the same may be amended, modified or otherwise
supplemented from time to time in accordance with its terms.

          "TRANSACTION" shall have the meaning set forth in SECTION 2(c) hereof.

          "TRANSFER AGENT" shall have the meaning set forth in SECTION 4 hereof.

          "WARRANTS" shall have the meaning set forth in the preamble hereof.

          "WARRANT EXERCISE DOCUMENTATION" shall have the meaning set forth in
SECTION 1 hereof.

          "WARRANT EXPIRATION DATE" means August 31, 2008.

                            [SIGNATURE PAGE FOLLOWS]


                                       12
<Page>

          IN WITNESS WHEREOF, the Company has caused this Warrant Certificate to
be duly executed as of the Issue Date.


                                        COMPANY

                                        ELECTRIC CITY CORP.,
                                        a Delaware corporation


                                        By:    /s/ Jeffrey Mistarz
                                           _____________________________________

                                        Name:  Jeffrey Mistarz
                                             ___________________________________

                                        Title: CFO
                                              __________________________________


ATTEST:

     /s/ Greg M. Rice
__________________________________

<Page>

                             Form of Assignment Form

                  [To be executed upon assignment of Warrants]

     The undersigned hereby assigns and transfers unto ______________________,
whose Social Security Number or Tax ID Number is ____________________ and whose
record address is ___________________________________ the rights represented by
the attached Warrant Certificate with respect to ___ Warrants to which the
attached Warrant Certificate relates, and irrevocably appoints _______________
as agent to transfer this security on the books of the Company. Such agent may
substitute another to act for such agent.

                                        Signature:


                                        ________________________________________
                                        (Signature must conform in all respects
                                        to name of holder as specified on the
                                        face of the Warrant Certificate)

                                        Signature Guarantee:


                                        ________________________________________

Date:
     _____________________________

<Page>

               (SUBSCRIPTION FORM TO BE EXECUTED UPON EXERCISE OF
                          SOME OR ALL OF THE WARRANTS)

          The undersigned, registered Holder, successor or assignee of such
registered Holder of the within Warrant Certificate, hereby:

          (a)  subscribes for ___ shares of Common Stock which the undersigned
is entitled to purchase under the terms of the within Warrant Certificate, (b)
makes the full cash payment therefor called for by the within Warrant
Certificate or elects a Cashless Exercise or In-Kind Exercise as provided
therein, and (c) directs that the Common Stock issuable upon exercise of said
Warrants be issued as described hereunder.

                                        ________________________________________
                                        (Name)


                                        ________________________________________
                                        (Address)


                                        ________________________________________
                                        SIGNATURE


Dated:
      ____________________________