<PAGE>

                                                                  EXHIBIT 4.15

             CONSENT AND AMENDMENT OF SECURITIES PURCHASE AGREEMENT,
                 STOCK TRADING AGREEMENT, STOCKHOLDERS AGREEMENT
                          AND INVESTOR RIGHTS AGREEMENT

         This Consent and Amendment of Securities Purchase Agreement, Stock
Trading Agreement, Stockholders Agreement and Investor Rights Agreement (this
"Consent") is dated as of the 29th day of November, 2001, and is made by and
among Newcourt Capital USA Inc., a Delaware corporation, EP Power Finance,
L.L.C., a Delaware limited liability company, Morgan Stanley Dean Witter Equity
Funding, Inc., a Delaware corporation, Originators Investment Plan, L.P, a
Delaware limited partnership, Duke Capital Partners, LLC, a Delaware limited
liability company (collectively, the "PURCHASERS"), Newcourt Capital Securities,
Inc., a Delaware corporation (the "PLACEMENT AGENT"), each of the members of
management (each, an "Officer") of Electric City Corp., a Delaware corporation
(the "COMPANY") whose name is set forth on the signature pages hereto, and Leaf
Mountain Company, LLC ("Leaf Mountain") and shall become effective upon the
Closing under the Additonal Securities Purchase Agreement referred to below.

                              W I T N E S S E T H:

         WHEREAS, the Purchasers and the Company entered into that certain
Securities Purchase Agreement, dated as of July 31, 2001 (as it may be amended
from time to time, the "Securities Purchase Agreement"), whereby the Company
sold and the Purchasers bought shares of the Company's Series A Convertible
Preferred Stock, par value $0.01 per share (the "Series A Preferred Stock"),
together with warrants to purchase Series A Preferred Stock, shares of Common
Stock and warrants to purchase Common Stock; and

         WHEREAS, Leaf Mountain and the Company have entered into that certain
Securities Purchase Agreement dated as of November 29, 2001 (as it may be
amended from time to time, the "Additional Securities Purchase Agreement"),
whereby the Company has agreed to sell and Leaf Mountain has agreed to purchase
from the Company shares of the Series A Preferred Stock, together with warrants
to purchase Series A Preferred Stock, shares of Common Stock and warrants to
purchase Common Stock; and

         WHEREAS, the Purchasers, the Placement Agent, the Officers and the
Company are parties to that certain Stock Trading Agreement dated as of July 31,
2001(as it may be amended from time to time, the "Stock Trading Agreement"); and

<PAGE>


         WHEREAS, the Purchasers and the Company are parties to that certain
Investor Rights Agreement dated as of July 31, 2001 (as it may be amended from
time to time, the "Investor Rights Agreement"); and

         WHEREAS, the Purchasers and the Company are parties to that certain
Stockholders Agreement dated as of July 31, 2001 (as it may be amended from time
to time, the "Stockholders Agreement"); and

         WHEREAS, it is a condition precedent to the obligation of Leaf Mountain
to purchase such securities pursuant to the Additional Securities Purchase
Agreement that the parties hereto enter into this Consent and the Purchasers,
the Placement Agent and the Officers desire to induce Leaf Mountain to purchase
such securities from the Company and accordingly are willing to enter into this
Consent;

         NOW, THEREFORE, in consideration of the premises and mutual agreements
contained herein, the parties hereto hereby agree as follows:

         1. CONSENT. Each of the Purchasers hereby consents to the Additional
Securities Purchase Agreement and the Joinder Agreement referred to therein and
to the consummation of the transactions contemplated by such agreements.

         2. AMENDMENT OF SECURITIES PURCHASE AGREEMENT. The Purchasers, the
Placement Agent, the Officers and the Company hereby agree that, effective upon
closing under the Additional Securities Purchase Agreement and the execution of
the Joinder Agreement by the Company and Leaf Mountain, the Securities Purchase
Agreement shall be amended such that (a) the term "Additional Purchaser"
wherever used therein refers to Leaf Mountain Company, LLC, an Illinois limited
liability company, and (b) Schedule 2.3 thereto shall be restated in the form
attached hereto as "Restated Schedule 2.3."

         3. AMENDMENT OF STOCK TRADING AGREEMENT. The Purchasers, the Placement
Agent, the Officers and the Company hereby agree that, effective upon closing
under the Additional Securities Purchase Agreement and the execution of the
Joinder Agreement by the Company and Leaf Mountain, the Stock Trading Agreement
shall be amended as follows:

         (a) The following additional definition shall be added:

                  "LEAF MOUNTAIN" shall mean Leaf Mountain Company, LLC, an
         Illinois limited liability company.

         (b) The definitions of Additional Purchase Agreement and Covered Stock
shall be amended and restated in their respective entireties as follows:


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<PAGE>

                  "ADDITIONAL PURCHASE AGREEMENT" means the Securities Purchase
         Agreement dated as of November 29, 2001 between the Company and Leaf
         Mountain providing for the issuance and sale of Series A Preferred
         Stock and Series A Preferred Stock Warrants and Common Stock and
         warrants to purchase shares of Common Stock to Leaf Mountain.

                  "COVERED STOCK" means for Leaf Mountain:

                  (a) during the period ending on November 30, 2002, 75% of
         total holdings of Common Stock (calculated assuming the exercise of all
         rights, options and warrants to purchase Common Stock or securities
         convertible or exchangeable for shares of Common Stock, and the
         conversion or exchange of all securities convertible or exchangeable
         for Common Stock) purchased under the Additional Purchase Agreement (as
         adjusted for stock splits, stock combinations and the like); and

                  (b) during the period commencing on December 1, 2002, if the
         Company has either

                           (i) closed on the issuance of at least 100,000
                  additional shares of Series A Preferred Stock for a gross
                  sales price of not less than $1,000,000 on or before November
                  30, 2002, or

                           (ii) satisfied each of the following requirements:
                  (A) reported positive consolidated EBITDA (as defined below)
                  for at least three (3) consecutive months, (B) continued
                  reporting positive EBITDA for each month during the period
                  commencing with the first month described in clause (A)
                  preceding through the end of the month of November, 2002, and
                  (3) had cash balances of not less than $3,000,000 on November
                  30, 2002,

         the percentage applicable under clause (a) above. But if the Company
         has not met the requirement in clause (b)(i) or all of the requirements
         in clause (b)(ii), then during the period commencing on December 1,
         2002 "Covered Stock" means 50% of Leaf Mountain's total holdings of
         Common Stock (calculated assuming the exercise of all rights, options
         and warrants to purchase Common Stock or securities convertible or
         exchangeable for shares of Common Stock, and the conversion or exchange
         of all securities convertible or exchangeable for Common Stock)
         purchased under the Additional Purchase Agreement (as adjusted for
         stock splits, stock combinations and the like).

         For purposes of this definition of Covered Stock, the term "EBITDA"
         means for any period, an amount equal to the Company's net income
         (determined in accordance with generally accepted accounting principles
         in the United States of America, applied consistently with past
         periods) for such period plus, to the extend deducted in determining
         such net income for such period, the following: (1) taxes, (2) interest
         expense, (3) depreciation and (4) amortization.


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<PAGE>

         (c) Clause (a) of Section 2.1shall be amended and restated in its
entirety as follows:

                  (a) During the term of this Agreement, no Party may sell any
         of its Common Stock into the public market before the completion of a
         Qualified Primary Offering; PROVIDED, HOWEVER, that if a Qualified
         Primary Offering is not completed within eighteen (18) months after the
         Effective Date, each Party may sell its Common Stock into the public
         market, severally and not jointly, subject to the following conditions:

         (d) Clause (iii) of Section 2.1(a) shall be amended and restated in its
entirety as follows:

            (3)   the number of shares of Common Stock sold by such Party on any
                  trading day may not exceed five percent of the Average Daily
                  Trading Volume, provided that, with respect to the Uncovered
                  Stock held by Leaf Mountain (but not by any successor to, or
                  transferee of, Leaf Mountain), the number of shares sold on
                  any trading day may not exceed the greater of 10,000 shares or
                  ten percent of the Average Daily Trading Volume;

         (e) Section 2.6 shall be amended and restated in its entirety as
follows:

                  2.6 UNCOVERED STOCK. During the term of this Agreement, Leaf
         Mountain may not sell shares of its Uncovered Stock into the public
         market before the completion of a Qualified Primary Offering; PROVIDED,
         HOWEVER, that if a Qualified Primary Offering is not completed within
         twelve (12) months after the Effective Date, Leaf Mountain (but not any
         successor to, or transferee of Leaf Mountain) may sell its shares of
         Uncovered Stock into the public market, but subject to the provisions
         of Section 2.1(a)(iii) herein, under this Agreement.

         4. AMENDMENT OF STOCKHOLDERS AGREEMENT. The Purchasers, the Placement
Agent, the Officers and the Company hereby agree that, effective upon closing
under the Additional Securities Purchase Agreement and the execution of the
Joinder Agreement by the Company and Leaf Mountain, the Stockholders Agreement
shall be amended as follows:

         (a) The following additional definition shall be added:

                  "LEAF MOUNTAIN" shall mean Leaf Mountain Company, LLC, an
         Illinois limited liability company.

         (b) The definition of Additional Purchase Agreement shall be amended
and restated in its entirety as follows:


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<PAGE>

                  "ADDITIONAL PURCHASE AGREEMENT" means the Securities Purchase
         Agreement dated as of November 29, 2001 between the Company and Leaf
         Mountain providing for the issuance and sale of Series A Preferred
         Stock and Series A Preferred Stock Warrants and Common Stock and
         warrants to purchase shares of Common Stock to Leaf Mountain.

         (c) Section 2.3 shall be amended and restated in its entirety as
follows:

                  2.3 BOARD OBSERVATION RIGHTS. If a Holder (other than the
         Additional Purchaser or its transferees) (a) possesses the right to
         designate for nomination to the Board its nominee pursuant to Section
         2.1(a), or (b) no longer possesses a right to designate for nomination
         to the Board its nominee pursuant to Section 2.1(a) because such
         Holders and its Affiliates hold less than an aggregate of 200,000
         shares of Series A Preferred Stock (as adjusted for stock splits, stock
         combinations and the like), but such Holder and its Affiliates hold at
         least an aggregate of 2,000,000 shares of the Common Stock (calculated
         assuming the exercise of all rights, options, warrants to purchase
         Common Stock or securities convertible or exchangeable for shares of
         Common Stock, and the exchange or conversion of all securities
         convertible or exchangeable for Common Stock), then such Holders shall
         be entitled to designate one individual to serve as a Board Observer.
         While the Additional Purchaser holds 100,000 or more shares of Series A
         Preferred Stock (as adjusted for stock splits, stock combinations and
         the like), then the Additional Purchaser shall be entitled to designate
         one individual to serve as a Board Observer. Any such Board Observer
         designated pursuant to this Section will be invited to attend all
         meetings of the Board and any Board committees as an observer and to
         receive copies of all materials and communications provided to the
         Board and Board committees when so distributed. The Board Observers
         will not be excluded from any portion of Board meetings, Board
         committee meetings or Board discussions except for those portions (x)
         in which the Company's counsel communicates with the Board on matters
         where Board Observer's attendance would result in loss of the
         attorney-client privilege for the Company and (y) in which, in the good
         faith judgment of counsel to the Company, participation of the Board
         Observers is not appropriate under applicable law.

         (d) Section 2.8 shall be amended and restated in its entirety as
follows:

                  2.8 AGREEMENT OF ADDITIONAL PURCHASERS REGARDING SPECIAL
         APPROVAL RIGHTS VOTE. In connection with any vote, approval or written
         consent of the holders of shares of Series A Preferred Stock pursuant
         to Section 2.5 of this Agreement (and/or Section 6(e) of the
         Certificate of Designations), each Additional Purchaser (and its
         Affiliates or their respective transferees) other than Leaf Mountain
         shall vote or otherwise grant its approval or written consent for its
         shares of Series A Preferred Stock (prior to the close of voting but
         after the votes, approvals or written consents of all of the other
         holders of Series A Preferred Stock casting votes, approvals or written
         consents have been tallied) in the same proportion to the aggregate
         affirmative and negative votes, approvals or written consents of the
         other

                                       5
<PAGE>

         holders of Series A Preferred Stock with respect to each proposal
         submitted for vote, approval or written consent.

                  5. AMENDMENT OF INVESTOR RIGHTS AGREEMENT. The Purchasers, the
         Placement Agent, the Officers and the Company hereby agree that,
         effective upon closing under the Additional Securities Purchase
         Agreement and the execution of the Joinder Agreement by the Company and
         Leaf Mountain, the Investor Rights Agreement shall be amended as
         follows:

          (a) The following additional definition shall be added:

                  "LEAF MOUNTAIN" shall mean Leaf Mountain Company, LLC, an
         Illinois limited liability company.

          (b) The definitions of Additional Purchase Agreement, Common Stock
Warrants and Eligible Securities shall be amended and restated in their
respective entireties as follows:

                  "ADDITIONAL PURCHASE AGREEMENT" means the Securities Purchase
         Agreement dated as of November 29, 2001 between the Company and Leaf
         Mountain providing for the issuance and sale of Series A Preferred
         Stock and Series A Preferred Stock Warrants and Common Stock and
         warrants to purchase shares of Common Stock to Leaf Mountain.

                  "COMMON STOCK WARRANTS" means (i) the warrants issued to each
         Investor pursuant to the Securities Purchase Agreement to purchase
         750,000 shares of Common Stock as evidenced by those certain Warrant
         Certificates, of even date herewith, between each Investor and the
         Company, as each such Warrant Certificate may be amended from time to
         time and (ii) the warrants issued to Leaf Mountain pursuant to the
         Additional Purchase Agreement to purchase 421,875 shares of Common
         Stock as evidenced by that certain Warrant Certificate between Leaf
         Mountain and the Company, dated as of even date herewith, as such
         Warrant Certificate may be amended from time to time.

                  "ELIGIBLE SECURITIES" means (i) the shares of Common Stock
         issued or issuable upon the conversion of the Series A Preferred Stock
         issued or issuable pursuant to the Securities Purchase Agreement or the
         Additional Purchase Agreement or issued or issuable upon exercise of
         the Series A Preferred Stock Warrants and conversion of the Series A
         Preferred Stock issued or issuable pursuant to such exercise; (ii) the
         shares of Common Stock issued or issuable upon exercise of the
         Placement Agent Warrants; (iii) the shares of Common Stock issued
         pursuant to the Securities Purchase Agreement; (iv) the shares of
         Common Stock issued to Leaf Mountain pursuant to the Additional
         Purchase Agreement, (v) the shares of Common Stock issued or issuable
         upon exercise of the Common Stock Warrants; and (vi) any other shares
         of Common Stock issued as (or issuable upon the conversion or exercise
         of any warrant, right or other security that is issued as) a dividend
         or other distribution with respect to or in exchange for or in
         replacement of, the shares described in clauses (i), (ii),


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<PAGE>

         (iii), (iv), (v) and this clause (vi); PROVIDED, HOWEVER, that the
         foregoing definition shall exclude in all cases any Eligible Securities
         sold by a Holder in a transaction in which its rights under this
         Agreement are not also assigned; and PROVIDED FURTHER, that any
         Eligible Securities sold pursuant to Rule 144 or sold in a registered
         public offering that has been declared effective shall no longer be
         Eligible Securities hereunder.

         (c) Section 2.1shall be amended by the addition thereto of the
following provision at the end thereof:

                   (d) In addition to any rights Leaf Mountain may have under
         clause (a) above, while it is the holder of not less than an aggregate
         of 750,000 shares of the Common Stock (calculated assuming the exercise
         of all rights, options, warrants to purchase Common Stock or securities
         convertible or exchangeable for shares of Common Stock), may deliver to
         the Company, on a single occasion, a Registration Request that the
         Company file and use its best efforts to cause to become effective a
         registration statement under the Securities Act with respect to
         Eligible Securities comprising not less than 750,000 shares of Common
         Stock, on the terms and subject to the other conditions applicable to
         any Registration Request under this Section. Within forty-eight (48)
         hours of receipt of such Registration Request, the Company shall
         provide written notice to all other holders of Series A Preferred Stock
         of such Registration Request.


         6. ADDITIONAL AGREEMENT RE ISSUANCES OF PREFERRED STOCK. The Company
agrees with Leaf Mountain that after closing under the Additional Securities
Purchase Agreement and the execution of the Joinder Agreement by the Company and
Leaf Mountain, the Company will not issue and sell shares of its preferred stock
to any Person on terms more favorable that those which are applicable to Leaf
Mountain unless the Company's board of directors has determined that in its
judgment such subsequent investor provides a demonstrable synergistic benefit to
the business of the Company.





          [The balance of this page has been left blank intentionally.
                            Signature page follows.]



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<PAGE>

         IN WITNESS WHEREOF, the parties hereto have caused this Consent and
Amendment of Securities Purchase Agreement, Stock Trading Agreement,
Stockholders Agreement and Investor Rights Agreement to be executed as of the
day and year first above written.

MANAGEMENT                               PURCHASERS

                                         NEWCOURT CAPITAL USA, INC.,

   /s/ John Mitola
-----------------------------
John Mitola
                                         By:    /s/ Karen Scowcroft
                                             -------------------------
                                         Name:    Karen Scowcroft
                                             -------------------------
                                         Title:    Vice President
                                             -------------------------
   /s/ Brian Kawamura
-----------------------------
Brian Kawamura
                                         NEWCOURT CAPITAL SECURITIES, INC.,


                                         By:   /s/ Robert Sexton
                                             -------------------------
   /s/ Jeff Mistarz                      Name:   Robert Sexton
-----------------------------                -------------------------
Jeff Mistarz                             Title:  Managing Director
                                             -------------------------


                                         EP POWER FINANCE, L.L.C.,

                                         By:   /s/ Mark Tarini
                                             -------------------------
   /s/ Denis Enberg                      Name:    Mark Tarini
-----------------------------                -------------------------
Denis Enberg (with respect to            Title:  Managing Director
50,000 shares of Common Stock)               -------------------------


                                         MORGAN STANLEY DEAN WITTER
                                         EQUITY FUNDING, INC.


  /s/ Michael Pokora                     By:  /s/ Thomas A. Clayton
----------------------------                 -------------------------
Michael Pokora                           Name:  Thomas A. Clayton
                                             -------------------------
                                         Title:  Vice President
                                             -------------------------


                                       8
<PAGE>


PLACEMENT AGENT                          ORIGINATORS INVESTMENT PLAN, L.P.

                                         By: MSDN
NEWCOURT CAPITAL SECURITIES              By: MSDW OIP Investors, Inc., its
INC.                                         general partner


By: /s/ Robert Sexton                    By: /s/ Thomas A. Clayton
    -----------------------                  ------------------------------
Name:  Robert Sexton                     Name:  Thomas A. Clayton
    -----------------------                  ------------------------------
Title: Managing Director                 Title: Vice President
    -----------------------                  ------------------------------


                                         DUKE CAPITAL PARTNERS, L.L.C.,


                                         By:  /s/ Gerald Stalun
                                             ------------------------------
                                         Name:  Gerald Stalun
                                             ------------------------------
                                         Title: Managing Director
                                             ------------------------------


                                         LEAF MOUNTAIN COMPANY, LLC


                                         By:  /s/ John J. Jiganti
                                             ------------------------------
                                         Name:  John J. Jiganti
                                             ------------------------------
                                         Title: Manager
                                             ------------------------------



                                       9
<PAGE>

                              RESTATED SCHEDULE 2.3




         In addition to the terms, conditions and limitations regarding the
Additional Purchase Agreement and the Additional Purchaser set forth in the
Securities Purchase Agreement and the Ancillary Agreements, the following
additional or different terms shall be reflected in the Additional Purchase
Agreement and/or the other instruments, documents and agreement executed and
delivered in connection therewith:

         1. The Additional Purchaser will not have rights to participate as a
lender in the Company's Shared Savings Program like the Purchasers.

         2. The Additional Purchase Agreement shall not contain covenants
contained in Section 4.2 of the Securities Purchase Agreement (other than the
first sentence thereof) and the Additional Purchaser shall not have rights to
participate in any approvals sought pursuant to Section 4.1 of the Securities
Purchase Agreement.

         3. The Placement Agent will not be paid any placement fee nor will it
receive any additional warrants to purchase Common Stock or Series A Preferred
Stock Warrants in respect of the purchase and sale of securities by the
Additional Purchaser or upon any exercise of any Series A Preferred Stock
Warrants or warrants to purchase shares of Common Stock acquired by the
Additional Purchaser pursuant to the Additional Purchase Agreement.




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