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                                                                  EXHIBIT 4.16

                                     JOINDER
                                       TO
                INVESTOR RIGHTS AGREEMENT, STOCKHOLDERS AGREEMENT
                           AND STOCK TRADING AGREEMENT


         This JOINDER TO INVESTOR RIGHTS AGREEMENT, STOCKHOLDERS AGREEMENT AND
STOCK TRADING AGREEMENT (this "AGREEMENT") is made as of November 29, 2001, by
and between Electric City Corp., a Delaware corporation (the "COMPANY"), and
Leaf Mountain Company, LLC an Illinois limited liability company ("PURCHASER").

                                   WITNESSETH

         WHEREAS, the Company, EP Power Finance, L.L.C., a Delaware limited
liability company, Newcourt Capital USA Inc., a Delaware corporation, Morgan
Stanley Dean Witter Equity Funding, Inc., a Delaware corporation, Originators
Investment Plan, L.P., a Delaware limited partnership, and Duke Capital
Partners, LLC, a Delaware limited liability company (collectively, the
"INVESTORS"), entered into that certain Securities Purchase Agreement dated as
of July 31, 2001 (the "SECURITIES PURCHASE AGREEMENT"), pursuant to which the
Company sold, and the Investors acquired, shares of the Company's Series A
Preferred Stock, par value $0.01 per share (the "SERIES A PREFERRED STOCK"),
shares of Company common stock, warrants to purchase Company common stock, and
warrants to purchase Series A Preferred Stock;

         WHEREAS, in connection with the Securities Purchase Agreement, the
Company and the Investors entered into an Investor Rights Agreement dated as of
July 31, 2001, as amended by that certain Consent and Amendment of Securities
Purchase Agreement, Stock Trading Agreement, Stockholders Agreement and Investor
Rights Agreement of even date herewith, copies of which are attached hereto as
EXHIBIT "A" (collectively, the "INVESTOR RIGHTS AGREEMENT");

         WHEREAS, in connection with the Securities Purchase Agreement, the
Company and the Investors entered into a Stockholders Agreement dated as of July
31, 2001, as amended by that certain Consent and Amendment of Securities
Purchase Agreement, Stock Trading Agreement, Stockholders Agreement and Investor
Rights Agreement of even date herewith, copies of which are attached hereto as
EXHIBIT "B" (the "STOCKHOLDERS AGREEMENT");

         WHEREAS, in connection with the Securities Purchase Agreement, the
Company and the Investors entered into a Stock Trading Agreement dated as of
July 31, 2001, as amended by that certain Consent and Amendment of Securities
Purchase Agreement, Stock Trading Agreement, Stockholders Agreement and Investor
Rights Agreement of even date herewith, copies of which are attached hereto as
EXHIBIT "C" (the "STOCK TRADING AGREEMENT");

         WHEREAS, the Company and Purchaser are entering into that certain
Securities Purchase Agreement of even date herewith (the "ADDITIONAL PURCHASE
AGREEMENT"); and

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         WHEREAS, as a condition to entering into the Additional Purchase
Agreement, the Company requires Purchaser to enter into this Agreement and
accept the rights and obligations created pursuant to the Investor Rights
Agreement, the Stockholders Agreement and the Stock Trading Agreement.



                                    AGREEMENT

         NOW, THEREFORE, in consideration of the mutual covenants contained
herein and other good and valuable consideration, the receipt and sufficiency of
which are hereby acknowledged, the parties to this Agreement hereby agree as
follows:

1. DEFINITIONS. Capitalized terms used herein and not otherwise defined herein
shall have the meanings given to them in the Additional Purchase Agreement.

2. JOINDER.

         (a) Each of the Company and Purchaser hereby agrees that, from and
after the date hereof, Purchaser shall be a party to and bound by the Investor
Rights Agreement as if Purchaser were an Investor and Holder (each as defined in
the Investor Rights Agreement) thereunder.

         (b) Each of the Company and Purchaser hereby agrees that, from and
after the date hereof, Purchaser shall be a party to and bound by the
Stockholders Agreement as if Purchaser were a Holder (as defined in the
Stockholders Agreement) thereunder.

         (c) Each of the Company and Purchaser hereby agrees that, from and
after the date hereof, Purchaser shall be a party to and bound by the Stock
Trading Agreement as if Purchaser were a Purchaser and Party (each as defined in
the Stock Trading Agreement) thereunder.

3. REPRESENTATIONS. Purchaser hereby represents and warrants to the Company that
this Agreement has been duly executed and delivered by Purchaser and constitutes
the valid and binding obligation of Purchaser, enforceable in accordance with
its terms, subject to bankruptcy, insolvency, fraudulent transfer,
reorganization, moratorium and similar laws of general applicability relating to
or affecting creditors' rights and to general equity principles. Purchaser
hereby acknowledges it has received a copy of the Investor Rights Agreement, the
Stockholders Agreement and the Stock Trading Agreement.

4. MISCELLANEOUS.

         4.1 SUCCESSORS AND ASSIGNS. All terms, covenants, agreements,
representations, warranties and undertakings in this Agreement made by and on
behalf of the Company or

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Purchaser shall bind and inure to the benefit of the respective successors and
assigns of such party whether so expressed or not.

         4.2 AMENDMENTS AND WAIVERS. Changes in or additions to this Agreement
may be made or compliance with any term, covenant, agreement, condition or
provision set forth herein may be omitted or waived, only in accordance with the
provisions of the Investor Rights Agreement, the Stockholders Agreement or the
Stock Trading Agreement, as applicable.

         4.3 GOVERNING LAW. This Agreement shall be governed and construed in
accordance with the laws of the State of New York without giving effect to the
conflict of laws principles thereof.

         4.5 COUNTERPARTS. This Agreement may be executed in counterparts, each
of which shall together constitute one and the same instrument.

         4.6 EFFECT OF HEADINGS. The section and paragraph headings herein are
for convenience only and shall not effect the construction hereof.

         4.7 ENTIRE AGREEMENT. This Agreement, the Investor Rights Agreement,
the Stockholders Agreement, the Stock Trading Agreement and the Additional
Purchase Agreement constitute the entire agreement between the Company and
Purchaser with respect to the subject matter hereof. This Agreement supersedes
all prior agreements between the parties with respect to the subject matter
hereof.

         4.8 SEVERABILITY. The invalidity or unenforceability of any provision
hereof shall in no way affect the validity or enforceability of any other
provision.

                            [SIGNATURE PAGE FOLLOWS]






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IN WITNESS WHEREOF, the undersigned have executed this Agreement as of the date
first written above.

THE COMPANY

ELECTRIC CITY CORP., a Delaware corporation


By:   /s/ John P. Mitola
     -------------------------

Name:  John P. Mitola
     -------------------------

Title:  CEO
     -------------------------

PURCHASER

LEAF MOUNTAIN COMPANY, LLC, An Illinois limited liability company

By:  /s/ John J. Jiganti
     -------------------------

Name:   John J. Jiganti
     -------------------------

Title:   Manager
     -------------------------




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