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                                                                   EXHIBIT 10.11

                                 AMENDMENT NO. 4
                                       TO
                              EMPLOYMENT AGREEMENT

      THIS AMENDMENT NO. 4 TO EMPLOYMENT AGREEMENT (this "Amendment") is made
and entered into as of January 1, 2002, by and between METRETEK TECHNOLOGIES,
INC., a Delaware corporation (the "Corporation"), and A. BRADLEY GABBARD
("Officer").

                                    RECITALS

      WHEREAS, the Corporation and Officer have previously entered into that
certain Employment Agreement, dated as of June 11, 1991, as previously amended
as of July 14, 1997, December 3, 1998 and January 1, 2000 (as so amended and as
the same may hereafter be amended or otherwise modified from time to time, the
"Employment Agreement"); and

      WHEREAS, the Corporation and Officer now desire to amend the Employment
Agreement in order to extend the period of Officer's employment with the
Corporation; and

                                    AGREEMENT

      NOW, THEREFORE, in consideration of the premises and other good and
valuable consideration, the receipt and sufficiency of which are hereby
acknowledged, the parties hereto, intending to be legally bound hereby, agree as
follows:

      SECTION 1. AMENDMENTS TO EMPLOYMENT AGREEMENT. Effective as of the date
hereof, Section 2.1 of the Employment Agreement is hereby amended to read in its
entirety as follows:

            "2.1 Basic Term. The term of Officer's employment under this
            Agreement shall continue for a period of two years until December
            31, 2003, unless terminated earlier pursuant to this Section 2 (the
            "Employment Period"); provided, however, that unless the Corporation
            or Officer gives to the other written notice at least six months
            prior to the expiration of such two-year term or of any successive
            one-year extension term as provided hereafter, the Employment Period
            shall be automatically extended for successive one-year terms,
            unless and until terminated pursuant to this Agreement."

      SECTION 2. EFFECT OF AMENDMENT. From and after the date hereof, the term
"Employment Period" as used in the Employment Agreement shall be deemed to refer
to the Employment Period as such term is defined in this Amendment. Except as
and to the extent expressly modified by this Amendment, the Employment Agreement
shall remain in full force and effect in all respects in accordance with its
terms, and any reference to the Employment Agreement from and after the date
hereof shall be deemed to be a reference to the Employment Agreement as modified
by this Amendment.

      SECTION 3. GOVERNING LAW. This Amendment shall be governed by and
construed in accordance with the laws of the State of Colorado.

      SECTION 4. COUNTERPARTS. This Amendment may be executed in one or more
counterparts, each of which shall be deemed to be an original, but all of which
taken together shall constitute one and the same instrument.
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      IN WITNESS WHEREOF, this Amendment No. 4 to Employment Agreement has been
duly executed and delivered by or on behalf of the undersigned as of the date
first written above.

                                               CORPORATION:

                                               METRETEK TECHNOLOGIES , INC.

                                               By: /s/ W. Phillip Marcum
                                                  ------------------------------
                                                   W. Phillip Marcum, President


                                               OFFICER:

                                               /s/ A. Bradley Gabbard
                                               ---------------------------------
                                               A. Bradley Gabbard