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                                                                    Exhibit 4.13

    Form of Common Stock Purchase Warrant held by John A. Harpole






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THIS WARRANT AND THE SHARES ISSUABLE UPON THE EXERCISE OF THIS WARRANT HAVE NOT
BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED (THE "SECURITIES
ACT"), OR THE SECURITIES LAWS OF ANY STATE AND MAY NOT BE OFFERED, SOLD,
TRANSFERRED OR OTHERWISE DISPOSED OF UNLESS SUCH TRANSACTION IS REGISTERED UNDER
THE SECURITIES ACT AND ANY APPLICABLE STATE SECURITIES LAWS OR UNLESS SUCH
TRANSACTION IS EXEMPT FROM SUCH SECURITIES REGISTRATION REQUIREMENTS AND THE
COMPANY HAS RECEIVED AN OPINION OF COUNSEL, SATISFACTORY TO THE COMPANY, TO THAT
EFFECT. THIS WARRANT IS SUBJECT TO FURTHER RESTRICTIONS ON TRANSFER SET FORTH
HEREIN.


                           METRETEK TECHNOLOGIES, INC.

                        WARRANT TO PURCHASE COMMON STOCK


WARRANT TO PURCHASE                           ISSUE DATE: SEPTEMBER __, 1999
60,000 SHARES OF COMMON STOCK                 EXPIRATION DATE: SEPTEMBER__, 2002


THIS CERTIFIES THAT, for value received, ______________ (the "Holder"), is
entitled to purchase up to 60,000 shares of Common Stock, par value $.01 per
share (the "Shares"), of Metretek Technologies, Inc., a Delaware corporation
(the "Company"), at the exercise price per Share (the "Exercise Price") and
during the periods set forth in Section 2 below, as adjusted pursuant to Section
11 below, until 5:00 p.m., Denver, Colorado time on September __, 2002 (the
"Expiration Date"), upon the terms and subject to the conditions set forth in
this Warrant.


         The Shares or other property or securities issuable upon the exercise
of the Warrants are hereinafter referred to as the "Warrant Shares" and the
exercise price per Warrant Share in effect at any time and as adjusted from time
to time is hereinafter referred to as the "Exercise Price."

         1. Method of Exercise of Warrant. This Warrant may be exercised by the
Holder in whole at any time or in part from time to time within the period
specified herein by the presentation and surrender of this Warrant, together
with the Form for Exercise of Warrants attached hereto ("Exercise Form") duly
executed by Holder, to the Company at its principal executive offices,
accompanied by payment, by bank certified or cashier's check payable to the
order of the Company, or by wire transfer of immediately available funds to an
account designated by the Company, in the amount equal to the number of Warrant
Shares for which the Warrant is being exercised multiplied by the Exercise Price
of such Warrant Shares. Upon the Holder's exercise of this Warrant in accordance
with the terms and conditions hereof, the Company shall issue the number of
Warrant Shares to the Holder specified on the Exercise Form.



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         2. Number of Warrant Shares: Exercisability of Warrants.

            (a) Generally. Upon the terms and subject to the conditions set
forth in this Warrant, the Holder is entitled to purchase 60,000 Shares, at an
Exercise Price per Share set forth below, as such number of Shares and/or
Exercise Price are adjusted from time to time hereunder.

            (b) Warrant Tranches. This Warrant shall become exercisable and vest
in three Warrant tranches of 20,000 Shares each (each, a "Tranche"). Each
Tranche shall become vested on the date and at the Exercise Price set forth
below:

         Vesting Date              Number of Shares Vesting      Exercise Price
         ------------              ------------------------      --------------

         September ___, 1999                20,000              $4.50 per share
         March ___, 2000                    20,000              $5.00 per share
         March ___, 2001                    20,000              $5.50 per share

This Warrant shall be exercisable from time to time only for the number of
Warrant Shares which have vested as of such time.

            (c) Expiration of Warrants. The Warrants shall expire and become
unexercisable upon the Expiration Date.

         3. Exercise in Part. If this Warrant is exercised in part only prior to
the Expiration Date, the Company shall, upon surrender of this Warrant for
cancellation, execute and deliver a new certificate evidencing the right of the
Holder to receive the balance of the Warrant Shares hereunder.

         4. Status as Stockholder After Exercise. Upon receipt by the Company of
this Warrant and the Exercise Form at the principal executive offices of the
Company in proper form for exercise and the Exercise Price in full, the Holder
shall be deemed to be the holder of record of the Warrant Shares issuable upon
such exercise, notwithstanding that certificates representing such Warrant
Shares shall not then be actually delivered to the Holder. If the stock transfer
books of the Company shall be closed on the date of receipt of this Warrant, the
Holder shall be deemed to be the Holder of such Warrant Shares on the next
succeeding day on which the stock transfer books of the Company shall be opened.

         5. Delivery of Stock Certificates Upon Exercise. As soon as practicable
after the exercise of this Warrant, in whole or in part, the Company shall cause
to be issued in the name of and delivered to the Holder a certificate or
certificates evidencing the number of fully paid and nonassessable Warrant
Shares to which the Holder shall be entitled as a result of such exercise,
together with any other property to which the Holder is entitled upon such
exercise.

         6. Reservation of Warrant Shares. The Company shall at all times
reserve and keep available, solely for issuance and/or delivery upon exercise of
this Warrant, such number of Warrant Shares as shall then be issued upon the
exercise of this Warrant. All Warrant Shares issued upon exercise hereof shall,
upon such issuance, be fully paid and nonassessable.




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         7. No Fractional Shares. No fractional Warrant Shares shall be issued
upon the exercise, in whole or in part, of this Warrant. If fractional Warrant
Shares would be issuable upon exercise of this Warrant, the Company shall, in
lieu thereof, pay to the Holder an amount in cash equal to such fraction
multiplied by the then "current market value" of such fractional Warrant Shares.
For purposes of this paragraph only, the "current market value" of the Warrant
Shares shall be equal to the closing sale price of the Shares on the Nasdaq
Stock Market, so long as they are listed thereon, and thereafter the closing
sale price (or, if not available on such date, the average of the high and low
bid price for such date) of the Shares on any national securities exchange or
any other stock exchange, stock market or stock quotation system which
constitutes the primary market on which the Shares are then traded or quoted. If
the Shares are not listed or traded on any stock exchange, stock market or stock
system, then the "current market value" shall be an amount, not less than book
value, as determined in good faith by the Board of Directors of the Company.

         8. Rights of the Holder Prior to Exercise. The Holder shall not, solely
by virtue of this Warrant, be entitled to any voting or other rights of a
stockholder of the Company, either at law or equity, prior to the exercise of
this Warrant upon the terms and conditions set forth herein, and the rights of
the Holder are limited to those expressed in this Warrant and are not
enforceable against the Company except to the extent expressly set forth herein.

         9. Ownership of Warrants. The Company shall be entitled to treat the
registered Holder as the absolute owner hereof for all purposes and shall not be
bound to recognize any equitable or other claim to or interest in the Warrant on
the part of any other person.

         10. Assignment and Exchange of Warrants. Upon any registration of
transfer, the Company shall deliver a new Warrant or Warrants to the person
entitled thereto. This Warrant may be exchanged, at the option of the Holder
thereof, for another Warrant, or other Warrants of different denominations, of
like tenor and representing in the aggregate the right to purchase a like number
of Warrant Shares (or portions thereof), upon surrender to the Company or its
duly authorized agent. Notwithstanding anything contained herein to the
contrary, the Company shall have no obligation to cause Warrants to be
transferred on its books to any person if, in the opinion of counsel to the
Company, such transfer does not comply with the provisions of the Act and any
applicable state securities laws and the rules and regulations thereunder.

         11. Adjustment of Exercise Price and Type of Warrant Shares. The
Exercise Price in effect at any time and the number and kind of securities
purchasable upon the exercise of this Warrant shall be subject to adjustment
from time to time upon the happening of certain events as follows:

             (a) In case the Company shall (i) declare a dividend or make a
distribution on its outstanding Shares, in each case, in Shares, (ii) subdivide
or reclassify its outstanding Shares into a greater number of Shares, or (iii)
combine or reclassify its outstanding Shares into a smaller number of Shares,
the Exercise Price in effect at the time of the record date for such dividend or
distribution or of the effective date of such subdivision, combination or
reclassification shall be proportionately adjusted so that after such event the
Exercise Price shall equal the price determined by multiplying the Exercise
Price by a fraction, the denominator of which shall be the number of




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Shares outstanding after giving effect to such action, and the numerator of
which shall be the number of Shares outstanding immediately prior to such
action. Such adjustment shall be made successively whenever any event listed
above shall occur.

             (b) Upon each adjustment of the Exercise Price pursuant to the
provisions of this Section 11, the number of Warrant Shares issuable upon the
exercise at the adjusted Exercise Price of each Warrant shall be adjusted so
that after the event necessitating the adjustment to the Exercise Price, the
number of Warrant Shares into which this Warrant shall be exercisable shall be
equal to the nearest number of whole Shares determined by multiplying a number
equal to the Exercise Price in effect immediately prior to such adjustment by
the number of Warrant Shares issuable upon exercise of this Warrant immediately
prior to such adjustment and dividing the product so obtained by the adjusted
Exercise Price.

             (c) For the purposes of this Warrant, the term "Shares" shall mean
(i) the class of stock designated as Shares of Common Stock in the Certificate
of Incorporation of the Company as amended as of the date hereof, or (ii) any
other classes of stock resulting from successive changes or reclassifications of
such Common Stock consisting solely of changes in par value, or from par value
to no par value, or from no par value to par value.

             (d) In case of any consolidation of the Company with, or merger of
the Company into, another entity (other than a consolidation or merger which
does not result in any reclassification or change of the outstanding Shares),
the entity formed by such consolidation or merger shall execute and deliver to
the Holder a supplemental warrant agreement providing that the Holder of this
Warrant shall have the right thereafter (until the expiration of such Warrant)
to receive, upon exercise of such Warrant, the kind and amount of shares of
stock and/or other securities and property received upon such consolidation or
merger by a holder of the number of Shares for which such Warrant might have
been exercised immediately prior to such consolidation, merger, sale or
transfer. Such supplemental warrant agreement shall provide for adjustments
which shall be identical to the adjustments provided in this Section 11. The
above provision of this subsection shall similarly apply to successive
consolidations or mergers.

             (e) No adjustment in the Exercise Price or the number of Warrant
Shares shall be required if such adjustment is less than one-tenth of one
percent (0.1%) of such Exercise Price or number of Warrant Shares; provided,
however, that any adjustment which by reason of this Section 11e) are not
required to be made shall be carried forward and taken into account in any
subsequent adjustment. All calculations under this Section 11 shall be made to
the nearest one-tenth of one cent ($0.001) and one-thousandth of one share
(.001).

             (f) In any case in which this Section 11 shall require that an
adjustment in the number of Warrant Shares be made effective as of a record date
for a specified event, the Company may elect to defer, until the occurrence of
such event, issuing to the Holder, if the Holder exercised this Warrant after
the record date, the Warrant Shares, if any, issuable upon such exercise over
and above the Warrant Shares, if any, issuable upon such exercise prior to such
adjustment; provided, however, that the Company shall deliver to the Holder a
due bill or other appropriate instrument evidencing the Holder's right to
receive such additional Warrant Shares upon the occurrence of the event
requiring such adjustment.




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             (g) Whenever there shall be an adjustment as provided in this
Section 11, the Company shall promptly cause written notice thereof to be sent
by certified mail, postage prepaid, to the Holder, at its address as it shall
appear in the Company's transfer books, which notice shall be accompanied by an
officer's certificate setting forth the number of Warrant Shares issuable upon
the exercise of this Warrant if such Warrant were exercisable on the date of
such notice, and setting forth a brief statement of the facts requiring such
adjustment and the computation thereof, which officer's certificate shall be
conclusive evidence of the correctness of any such adjustment absent manifest
error.

         12. Registration Rights.

             (a) Piggy-Back Registration.

                 (i) Right to Piggy-Back. If, at any time after February 1, 2000
and prior to the Expiration Date, the Company proposes to register with the
Securities and Exchange Commission (the "SEC") the sale for cash of any of its
shares of Common Stock by filing a registration statement under the Securities
Act of 1933, as amended (the "Securities Act"), for its own account or for the
account of any of its stockholders (except pursuant to registration statements
filed on Form S-4 or Form S-8 or any successor or similar forms or other
unsuitable forms), the Company shall promptly give written notice of such
proposed filing to Holder and offer Holder the opportunity to register such
number of Warrant Shares issuable upon execution of this Warrant as it may
request in writing. Upon the written request of Holder received by the Company
within fifteen (15) days after the giving of the notice by the Company, the
Company shall use its best efforts to cause the Shares that the Holder requests
to be so registered to be included in such registration.

                 (ii) Underwriting Procedures. If any registration pursuant to
this Section 12(a) shall be, in whole or in part, in connection with an
underwritten public offering of Common Stock of the Company, then the Company
shall not be required to include any Warrant Shares in the registration unless
Holder accepts the terms and conditions of the underwriting as agreed upon
between the Company and the underwriters. If the managing underwriter determines
and advises the Company in writing (which shall promptly notify Holder) that the
inclusion in the underwriting of all or any of the Warrant Shares proposed to be
included by Holder would be reasonably likely to jeopardize the successful
marketing of the securities proposed to be registered for the underwriting by
the Company or materially adversely affect the price, time or distribution of
the public offering, then the Company shall only be required to include the
number of the Warrant Shares that the managing underwriter determines in its
sole discretion, will not materially adversely affect the public offering, and,
if any such reduction is so determined by the managing underwriter to be
appropriate in accordance with the standards set forth above, then the number of
Warrant Shares requested to be included in the underwriting shall be reduced,
pro rata with other stockholders (other than those having and exercising demand
registration rights), if any, participating in the public offering, to the
number determined to be appropriate by the managing underwriter (which may
include a reduction to zero).

                 (iii) No Company Obligation. Neither the giving of a notice by
the Company nor any request by Holder under this Section 12(a) shall, in any
way, obligate the Company to file any registration statement at any time or
within any specific time period after



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receipt of Holder's written request and, notwithstanding the filing of any
registration statement, the Company may, at any time before the effective date
thereof, elect to delay or terminate the entire registration process for any
reason or no reason and without the consent of Holder, without any further
obligation to Holder in respect of such registration statement.

             (b) Demand Right. If, at any time prior to the Expiration Date, the
Company shall receive a written request ("Demand Request") from Holder for the
registration of any or all the Warrant Shares, provided that at the time of the
Demand Request at least a majority of the total Warrant Shares are still held of
record by Holder, then the Company, upon the terms and subject to the conditions
set forth in this Section 12(b), shall use its best efforts to cause all Warrant
Shares to be registered in an appropriate registration statement of the SEC as
shall be selected by the Company, provided that if the Company is eligible to
use Form S-3 (or any successor form thereto) for such registration, then such
registration statement shall be used unless such form is inappropriate or the
Company desires to use a different form. If Holder intends for the public
offering covered by its Demand Request to occur by means of an underwriting, it
shall so advise the Company as a part of its Demand Request, and the managing
underwriter of such underwritten public offering shall be selected by Holder and
shall be reasonably acceptable to the Company. The Company shall be obligated to
register the Warrant Shares under this Section 12(b) after receipt of a Demand
Request on one occasion only. The Company shall be entitled to include in any
registration statement filed pursuant to this Section 12(b) additional shares of
Common Stock for its own account and for the account of its other security
holders. If the managing underwriter advises the Company in writing that the
inclusion of any or all such additional shares of Common Stock would materially
adversely affect the marketing of the public offering of the Warrant Shares,
then the Company shall not be entitled to include such additional shares of
Common Stock in any such registration statement to the extent the managing
underwriter advises. Notwithstanding the provisions of this Section 12(b), the
Company shall have the right to delay or suspend the filing of a registration
statement for up to ninety (90) days from the time the filing thereof would
otherwise be required under this Section 12(b) if, in the good faith
determination of the Company's board of directors, such registration would be
seriously detrimental to the Company and its stockholders or would materially
adversely affect the business, affairs, properties, financial condition, results
of operations or prospects of the Company or any pending or proposed
acquisition, merger, reorganization, recapitalization or other transaction or
public offering of the Company's securities, or would require premature
disclosure thereof not in the best interests of the Company; provided, however,
that the Company shall not be entitled to exercise this right more than once. If
this Warrant, or any portion thereof, and/or the Warrant Shares are at any time
held by more than one person or entity, then the obligations of the Company
under this Section 12(b) shall only apply to a "50% holder". The term "50%
holder" as used in this Section 12(b) shall mean the holder or holders of at
least 50% of the Warrant Shares and shall include any owner or combination of
owners of such securities, which ownership shall be calculated by determining
the number of Warrant Shares then held by such owner or owners, as well as the
number of Warrant Shares then issuable upon exercise of this Warrant (or any
successor Warrants) held by such owner or owners.

             (c) Information. It shall be condition precedent to the obligation
of the Company hereunder to register the Warrant Shares under this Section 12(c)
that Holder furnish to the Company and the managing underwriters such
information regarding itself, the intended method of disposition of such
securities and such other information as the Company or the



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managing underwriter shall from time to time reasonably request and that shall
be reasonably required to effect the registration of the Warrant Shares.

             (d) Market Stand-Off. The Holder, including any assignee or
successors of Holder, agrees in connection with any underwritten public offering
of the Company's securities that upon the request of the managing underwriter,
it shall commit itself in writing not to sell or offer to sell any shares other
than such shares included in the underwritten public offering, during 30 days
prior to, and for a period not to exceed ninety (90) days after, the date of the
final prospectus used in such offering.

             (e) Expenses. Holder shall pay all underwriting and brokerage fees,
discounts and commissions related to the sale of the Warrant Shares in a public
offering registered pursuant to the provisions of this Section 12(e), together
with the fees and expenses of any separate counsel, accountants and other
advisors retained by Holder in connection with the offering. All other fees,
costs and expenses incurred in connection with any registration of public
offering including, but not limited to, all federal and state registration,
qualification, filing fees, printed and document distribution costs and
expenses, fees and disbursements of its counsel, accountants and other experts,
Nasdaq additional listing fees, transfer fees, exchange fees, fees of transfer
agents and registrants shall be borne as follows: (i) if pursuant to a demand
registration under Section 12(b), the Company shall bear all reasonable costs,
fees and expenses incurred by the Company (provided the offering being
registered is not pursuant to an underwriting), and (ii) if pursuant to a
piggy-back registration under Section 12(a), by the Company, except that Holder
shall bear its proportionate share of any such costs, fees and expenses to the
extent Warrant Shares of Holder are included in the registration.

             (f) Indemnification. If any of the Warrant Shares are included in a
registration, to the extent permitted by law, Holder shall indemnify and hold
harmless the Company, each of its directors, each of its officers who have
signed the registration statement, each person, if any, who controls the Company
within the meaning of Section 15 of Securities Act or Section 20 of the
Securities Exchange Act of 1934, as amended (the "Exchange Act"), any
underwriter, and any controlling person of any such underwriter, from and
against any and all losses, claims, liabilities, damages and expenses (including
any investigative, legal, accounting and other expenses reasonably incurred in
connection with, and any amount paid in settlement of, any action, suit or
proceeding or any claim (the "Damages") asserted to which any of the foregoing
persons may become subject under the Securities Act, the Exchange Act, or other
federal or state law, common law or otherwise, insofar as such Damages arise out
of or are based upon any untrue statement or alleged untrue statement of a
material fact contained in such registration statement, any preliminary
prospectus or final prospectus, or any amendments or supplements thereto, the
omission or alleged omission to state therein a material fact required to be
stated therein or necessary to make the statements therein not misleading, or
any violation or alleged violation by the Company of the Securities Act, the
Exchange Act, any state securities law or any rule or regulation promulgated
under the Securities Act, the Exchange Act or any state securities law
(collectively, a "Violation"), to the extent that such Violation occurs in
reliance upon and in conformity with written information furnished to the
Company by the Holder expressly for use in connection with such registration;
and Holder shall pay, as incurred, any legal or other expenses reasonably
incurred by any person intended to be indemnified pursuant to this Section 12(f)
in connection with the investigation or defense of any such Damages.



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             (g) Indemnification. If any of the Warrant Shares are included in a
registration, to the extent permitted by law, the Company shall indemnify and
hold harmless the Holder, each of its directors and officers from and against
any and all Damages asserted to which any of the foregoing persons may become
subject under the Securities Act, the Exchange Act, or other federal or state
law, common law or otherwise, insofar as such Damages arise out of or are based
upon any untrue statement or alleged untrue statement of a material fact
contained in such registration statement, any preliminary prospectus or final
prospectus, or any amendments or supplements thereto, the omission or alleged
omission to state therein a material fact required to be stated therein or
necessary to make the statements therein not misleading, or any Violation or
alleged Violation by the Holder, to the extent that such Violation occurs in
reliance upon and in conformity with written information furnished to the Holder
by the Company expressly for use in connection with such registration; and the
Company shall pay, as incurred, any legal or other expenses reasonably incurred
by any person intended to be indemnified pursuant to this Section 12(g) in
connection with the investigation or defense of any such Damages.

         13. Legend. The certificate or certificates evidencing the Warrant
Shares shall bear a legend in substantially the following form:

             THE SHARES REPRESENTED BY THIS CERTIFICATE HAVE NOT BEEN REGISTERED
             UNDER THE SECURITIES ACT OF 1933, AS AMENDED (THE "SECURITIES
             ACT"), OR THE SECURITIES LAWS OF ANY STATE AND MAY NOT BE OFFERED,
             SOLD, TRANSFERRED OR OTHERWISE DISPOSED OF UNLESS SUCH TRANSACTION
             IS REGISTERED UNDER THE SECURITIES ACT AND ANY APPLICABLE STATE
             SECURITIES LAWS OR UNLESS SUCH TRANSACTION IS EXEMPT FROM SUCH
             SECURITIES REGISTRATION REQUIREMENTS AND THE COMPANY HAS RECEIVED
             AN OPINION OF COUNSEL, SATISFACTORY TO THE COMPANY, TO THAT EFFECT.

         14. Issue Tax. The issuance of certificates for Warrant Shares upon
exercise of this Warrant shall be made without charge to the Holder for any
issuance tax in respect thereof; provided, however, that the Company shall not
be required to pay any tax which may be payable in respect of any transfer
involved in the issuance and delivery of any certificate in a name other than
that of the Holder.

         15. Limitations on Disposition of Warrant. Neither this Warrant nor,
unless registered under the Securities Act and applicable securities laws, as
contemplated by Section 12 hereof, the Warrant Shares issuable upon exercise of
the Warrant, may be offered, sold, assigned, hypothecated or otherwise
transferred, in whole or in part, except (i) to the officers, directors,
shareholders or employees of the Holder, (ii) by will or the laws of descent and
distribution as a result of the death of any permitted transferee, or (iii) to
any successor to the business of the Holder. In addition, neither this Warrant
nor, until registered under the Securities Act and applicable securities laws,
any Warrant Shares issued upon exercise of this Warrant, may be pledged,
offered, sold, assigned, hypothecated or otherwise transferred until (i) such
transaction has been registered under the Securities Act and any applicable
state securities laws, or (ii) such transaction is exempt from such securities
registration requirements and the Company has received an opinion of counsel to
which opinion is satisfactory to the Company, to that effect. It shall be a
condition to the transfer of this Warrant and any Warrant Shares that any
transferee hereof or thereof deliver to the Company its written agreement to
accept and be bound by all of the terms and conditions of this Warrant.



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         16. Lost, Stolen, Mutilated or Destroyed Warrant. Upon receipt of
evidence satisfactory to the Company of the loss, theft, destruction, or
mutilation of any Warrant (and upon surrender of any Warrant if mutilated), and
upon reimbursement of the Company's reasonable incidental expenses and, if
reasonably requested, an indemnity reasonably acceptable to the Company, the
Company shall execute and deliver to the Holder thereof a new Warrant of like
date, tenor, and denomination.

         17. Securities Law Representation. The Holder and each transferee of
this Warrant or of the Warrant Shares issuable upon the exercise of this
Warrant, by their acceptance of this Warrant or of any Warrant Shares, each
hereby represents and warrants that this Warrant and the Warrant Shares issuable
upon exercise of this Warrant are being acquired or will be acquired for
investment purposes for the account of the holder of such securities with no
intention of a sale, transfer or other distribution that is not in compliance
with the Securities Act and applicable state securities laws.

         18. No Impairment. The Company will not, by any voluntary action, avoid
or seek to avoid the observance or performance of any of the terms to be
observed or performed hereunder by the Company, but will at all times in good
faith assist in the carrying out of all the provisions of this Warrant and in
the taking of all such action as may be necessary or appropriate in order to
protect the rights of the Holder of this Warrant against impairment.

         19. Waiver. This Warrant and any term hereof may be changed, waived,
discharged or terminated only by an instrument in writing signed by the party
against which enforcement of such change, waiver, discharge or termination is
sought.

         20. Notices. All notices, payments, requests and demands and other
communications required or permitted under this Warrant shall be deemed to have
been duly given, delivered and made if in writing and if served either by
personal delivery to the party for whom it is intended or by being deposited
postage prepaid, certified or registered mail, return receipt requested, to the
address of the Holder at the last address as appears on the books of the Company
or its stock transfer agent, if any, and to the Company at its principal
executive offices.

         21. Governing Law. This Warrant shall be construed and enforced in
accordance with and governed by the internal substantive laws of the State of
Delaware, without giving effect to any change or conflict of law principles.

         22. Further Assurances. The parties agree to execute, acknowledge and
deliver any and all such other documents and to take any and all such other
actions as may, in the reasonable opinion of either of the parties hereto, be
necessary or convenient to carry out more efficiently any or all of the purposes
of this Warrant.

         23. Severability. Any provision of this Warrant which shall be
prohibited by law or otherwise held invalid shall be ineffective only to the
extent of such prohibition or invalidity and shall not invalidate or otherwise
render ineffective any or all of the remaining provisions of this Warrant.



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         24. Parties in Interest. This Warrant and the various rights and
obligations arising hereunder shall be binding upon and shall inure to the
benefit of the parties hereto and to each and all of their respective successors
and permitted assigns.

         25. Amendments. Neither this Warrant nor any of the terms and
conditions hereof shall be amended or modified in any respect except in a
writing executed by the Company and Holder.

         IN WITNESS WHEREOF, the Company has caused this Warrant to be executed
by its President and attested by its Secretary as of the _____ day of September,
1999.


                                         METRETEK TECHNOLOGIES, INC.



                                         By:_________________________________
                                            W. Phillip Marcum, President



ATTEST:


By: ____________________________
     Gary J. Zuiderveen, Secretary




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                          FORM FOR EXERCISE OF WARRANTS

     [TO BE EXECUTED BY THE HOLDER IN ORDER TO EXERCISE THE WITHIN WARRANT]

         The undersigned, the Holder of the within Warrant, hereby irrevocably
elects to exercise the right, represented by the within Warrant, to purchase
_____ shares of Common Stock, par value $.01 per share ("Shares"), of Metretek
Technologies, Inc., a Delaware corporation (the "Company"), in accordance with
the terms of the within Warrant. The undersigned requests that a certificate for
such Shares be issued in the name of, and delivered to:

                         Name: _______________________________
                         Address:_____________________________
                                 _____________________________
                         Social Security or Tax ID No. _______

and, if such number of Shares shall not be all the Shares issuable upon exercise
of the within Warrant, that a new Warrant exercisable on the same terms for the
balance of such Shares be registered in the name of, and delivered to, the
Holder at the address set forth below.

         Payment of the Exercise Price per Share required under the within
Warrant accompanies this Form.

         The undersigned hereby represents and warrants that the undersigned
owns the within Warrant free and clear of any and all claims, liens and/or
encumbrances and is acquiring such Shares for its own account for investment
purposes only, and not for resale or with a view to distribution of such Shares
or any part thereof.

Dated: ________________                     ____________________________________
                                            By:_________________________________
                                            Title:______________________________
                                            Address:____________________________
                                                    ____________________________
                                                    ____________________________


Number of Shares: _________________
Total Exercise Price:$_____________

                                            METRETEK TECHNOLOGIES, INC.

                                            By:_________________________________
                                            Its:________________________________

                                            Date:_______________________________




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<PAGE>   13

                               FORM OF ASSIGNMENT

          [TO BE EXECUTED BY THE HOLDER TO TRANSFER THE WITHIN WARRANT]


         FOR VALUE RECEIVED, the undersigned, as the registered Holder of the
within Warrant, hereby sells, assigns and transfers unto:

                            Name:______________________________
                            Address: __________________________
                                     __________________________
                            Social Security or Tax ID No.______


all of the undersigned's right, title and interest to and under such Warrant to
purchase ____ shares of Common Stock, par value $.01 per share, of Metretek
Technologies, Inc., a Delaware corporation (the "Company"), evidenced by the
within Warrant, and does hereby irrevocably constitute and appoint ____________
attorney to make such transfer on the books of the Company, with full power of
substitution in the premises.



                                            -----------------------------------

Date:___________________________            By:_________________________________
                                            Title:

                                            ------------------------------------
                                            (Street Address)

                                            ------------------------------------
                                            (City),      (State)      (Zip Code)


                                            NOTE: The above signature must
                                            conform to the name of Holder as
                                            specified on the face of the within
                                            Warrant in every particular, without
                                            alteration or enlargement or any
                                            change whatsoever.





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