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                                                                   EXHIBIT 10.28

                              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. 18
                                                                              --

                               WARRANT CERTIFICATE

                       TO PURCHASE SHARES OF COMMON STOCK,

                           PAR VALUE $0.0001 PER SHARE

                                       OF

                               ELECTRIC CITY CORP.

                  THIS IS TO CERTIFY THAT Morgan Stanley Dean Witter Equity
Funding, Inc. or its registered assigns (the "HOLDER"), is the owner of 712,500
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:
        ____________________________