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                                                                     EXHIBIT 2.3



         AMENDMENT TO STOCK PURCHASE AGREEMENT AND EMPLOYMENT AGREEMENTS
                                DECEMBER 31, 2002


Reference is made to that certain Stock Purchase Agreement dated April 6, 2001
("Stock Purchase Agreement") by and among Metretek Technologies, Inc.,
PowerSecure, Inc. ("PowerSecure"), Stanley W. Timblin ("S. Timblin") and Jeffrey
W. Timblin ("J. Timblin"); and to that certain Employment and Non-Competition
Agreement dated April 10, 2001 by and among PowerSecure and S. Timblin, and to
that certain Employment and Non-Competition Agreement dated April 10, 2001 by
and among PowerSecure and J. Timblin (collectively, the "Timblin Employment
Agreements").

WHEREAS, the Stock Purchase Agreement provided for the purchase by PowerSecure
of 100% of the common stock of Industrial Automation Corp. ("IAC") from S.
Timblin and J. Timblin; and

WHEREAS, the Stock Purchase Agreement provides a mechanism for the adjustment of
the Purchase Price of such common stock based upon post-closing adjustments to
the IAC "net working capital" (as defined) that existed as of the date of
closing; and,

WHEREAS, the Stock Purchase Agreement provides that the purchase price
adjustment be based upon final adjustments to the net working capital after
consideration of actual collections of IAC and actual payments of IAC
liabilities, whether or not disclosed as of the closing date, that occurred
after the closing date; and,

WHEREAS, the Timblin Employment Agreements provided for certain Incentive
Compensation to be earned by S. Timblin and J. Timblin based upon the profits
derived by certain "Earnout Projects" anticipated to be awarded to IAC and
completed subsequent to closing; and,

WHEREAS, the Stock Purchase Agreement provides that in the event that the net
working capital Adjustment Amount is determined to be negative (S. Timblin and
J. Timblin owing PowerSecure), that such amount shall be offset against the
Incentive Compensation, provided that to the extent such Adjustment Amount is
not fully recovered by November 30, 2002, then such amount shall be paid by S.
Timblin and J. Timblin on or before December 31, 2002; and,

WHEREAS, as of December 31, 2002, there was in fact a negative Adjustment Amount
due to PowerSecure from S. Timblin and J. Timblin in the amount of $345,888.69,
as shown in the attached exhibit "A"; and,

WHEREAS, certain of the original concepts and expectations with respect to the
conduct of IAC's business and the employment of S. Timblin and J. Timblin have
changed, as described in the memo attached as exhibit "B".

NOW, THEREFORE, in consideration of the premises, mutual covenants and
agreements set forth herein, 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:

     1.   Section 1.4 "Purchase Price Adjustment" of the Stock Purchase
          Agreement is hereby terminated, eliminated and of no further force and
          effect. Any Adjustment Amount, which might have otherwise been
          calculated and be owing from one party to the other is hereby voided
          and forever terminated and forgiven.

     2.   Section 4.(b) of the Timblin Employment Agreements is hereby
          terminated, eliminated and of no further force and effect. Any actual
          or potential liability of PowerSecure to pay Incentive compensation to
          either S. Timblin or J. Timblin is voided and forever terminated and
          forgiven.

     3.   All other provisions of the Stock Purchase Agreement and the Timblin
          Employment Agreements remain unmodified and if full force and effect.


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         IN WITNESS WHEREOF, this Amendment to the Stock Purchase Agreement and
the Timblin Employment Agreements has been executed and delivered by or on
behalf of the parties hereto, effective as of the date first above written.



                                       /s/ Stanley W. Timblin
                                       --------------------------------
                                       Stanley W. Timblin, Individually

                                       /s/ Jeffrey W. Timblin
                                       --------------------------------
                                       Jeffrey W. Timblin, Individually



                                       POWERSECURE, INC.

                                       By: /s/ Sidney Hinton
                                           ----------------------------
                                       Its: CEO
                                           ----------------------------



                                       METRETEK TECHNOLOGIES, INC.

                                       By:  /s/ A. Bradley Gabbard
                                           ----------------------------
                                       Its: Exec. V. P.
                                           ----------------------------

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