<PAGE>

                                                                    EXHIBIT 10.1

                              MASTER REVOLVING NOTE
                 Variable Rate-Maturity Date-Obligatory Advances
                      (Business and Commercial Loan Only)

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AMOUNT            NOTE DATE            MATURITY DATE       TAX IDENTIFICATION #

$2,000,000.00    September 24, 2004    October 05, 2005       54-4867640
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On the Maturity Date, as stated above, for value received, the undersigned
promise(s) to pay to the order of COMERICA BANK ("Bank"), at
any office of the Bank in the State of California, TWO MILLION AND NO/100
Dollars (U.S.) (or that portion of it advanced by the Bank and not repaid as
later provided) with interest until maturity, whether by acceleration or
otherwise, or an Event of Default, as later defined, at a per annum rate equal
to the Bank's base rate from time to time in effect PLUS 1.000% per annum and
after that at a rate equal to the rate of interest otherwise prevailing under
this Note plus 3% per annum (but in no event in excess of the maximum rate
permitted by law). The Bank's "base rate" is that annual rate of interest so
designated by the Bank and which is changed by the Bank from time to time.
Interest rate changes will be effective for interest computation purposes as and
when the Bank's base rate changes. Interest shall be calculated on the basis of
a 360-day year for the actual number of days the principal is outstanding.
Accrued interest on this Note shall be payable on the 5th day of each MONTH
commencing NOVEMBER 05, 2004, until the Maturity Date when all amounts
outstanding under this Note shall be due and payable in full. If the frequency
of interest payments is not otherwise specified, accrued interest on this Note
shall be payable monthly on the first day of each month. If any payment of
principal of interest under this Note shall be payable on a day other than a day
on which the Bank is open for business, this payment shall be extended to the
next succeeding business day and interest shall be payable at the rate specified
in this Note during this extension. A late payment charge equal to 5% of each
late payment may be charged on any payment not received by the Bank within 10
calendar days after the payment due date, but acceptance of payment of this
charge shall not waive any Default under this Note.

The principal amount payable under this Note shall be the sum of all advances
made by the Bank to or at the request of the undersigned, less principal
payments actually received in cash by the Bank. The books and records of the
Bank shall be the best evidence of the principal amount and the unpaid interest
amount owing at any time under this Note and shall be conclusive absent manifest
error. No interest shall accrue under this Note until the date of the first
advance made by the Bank; after that interest on all advances shall accrue and
be computed on the principal balance outstanding from time to time under this
Note until the same is paid in full.

This Note and any other indebtedness and liabilities of any kind of the
undersigned (or any of them) to the Bank, and any and all modifications,
renewals or extensions of it, whether joint or several, contingent or absolute,
now existing or later arising, and however evidenced (collectively
"Indebtedness") are secured by and the Bank is granted a security interest in
all items deposited in any account of any of the undersigned with the Bank and
by all proceeds of these items (cash or otherwise), all account balances of any
of the undersigned from time to time with the Bank, by all property and any of
the undersigned from time to time in the possession of the Bank and by any other
collateral, rights and properties described in each and every deed of trust,
mortgage, security agreement, pledge, assignment and other security or
collateral agreement which has been, or will at any time(s) later be, executed
by any (or all) of the undersigned to or for the benefit of the Bank
(collectively "Collateral"). Notwithstanding the above, (i) to the extent that
any portion of the indebtedness is a consumer loan, that portion shall not be
secured by any deed of trust or mortgage on or other security interest in any of
the undersigned's principal dwelling or any of the undersigned's real property
which is not a purchase money security interest as to that portion, unless
expressly provided to the contrary in another place, or (ii) the undersigned (or
any of them) has(have) given or give(s) Bank a deed of trust or mortgage
covering real property, that deed of trust or mortgage shall not secure this
Note or any other indebtedness of the undersigned (or any of them), unless
expressly provided to the contrary in another place.

                                       1



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If the undersigned (or any of them) or any guarantor under a guaranty of all or
part of the Indebtedness ("guarantor") (i) fail(s) to pay any of the
Indebtedness when due, by maturity, acceleration or otherwise, or fail(s) to pay
any Indebtedness owing on a demand basis upon demand; or (ii) fail(s) to comply
with any of the terms or provisions of any agreement between the undersigned (or
any of them) or any such guarantor and the Bank; or (iii) become(s) insolvent or
the subject of a voluntary or involuntary proceeding in bankruptcy, or a
reorganization, arrangement or creditor composition proceeding, (if a business
entity) cease(s) doing business as a going concern, (if a natural person) die(s)
or become(s) incompetent, (if a partnership) dissolve(s) or any general partner
of it dies, becomes incompetent or becomes the subject of a bankruptcy
proceeding or (if a corporation of a limited liability company) is the subject
of a dissolution, merger or consolidation; or (a) if any warranty or
representation made by any of the undersigned or any guarantor in connection
with this Note or any of the Indebtedness shall be discovered to be untrue or
incomplete; or (b) if there is any termination, notice of termination, or breach
of any guaranty, pledge collateral assignment or subordination agreement
relating to all or any part of the Indebtedness; or (c) if there is any failure
by any of the undersigned or any guarantor to pay when due any of its
indebtedness (other than to the Bank) or in the observance of performance of any
term, covenant or condition in any document evidencing, securing or relating to
such indebtedness; or (d) if the Bank deems itself insecure believing that the
prospect of payment of this Note or any of the Indebtedness is impaired or shall
fear deterioration, removal or waste of any of the Collateral; or (e) if there
is filed or issued a levy or writ of attachment or garnishment or other like
judicial process upon the undersigned (or any of them) or any guarantor or any
of the Collateral, including, without limit, any accounts of the undersigned (or
any of them) or any guarantor with the Bank, then the Bank, upon the occurrence
of any of these events (each a "Default"), may at its option and without prior
notice to the undersigned (or any of them), declare any or all of the
indebtedness to be immediately due and payable (notwithstanding any provisions
contained in the evidence of it to the contrary), cease advancing money or
extending credit to or for the benefit of the undersigned under this Note or any
other agreement between the undersigned and Bank, terminate this Note as to any
future liability or obligation of Bank, but without affecting Bank's rights and
security interest in any Collateral and the Indebtedness of the undersigned to
Bank, sell or liquidate all or any portion of the Collateral, set off against
the indebtedness any amounts owing by the Bank to the undersigned (or any of
them), charge interest at the default rate provided in the document evidencing
the relevant Indebtedness and exercises any one or more of the rights and
remedies granted to the Bank by any agreement with the undersigned (or any of
them) or given to it under applicable law. In addition, if this Note is secured
by a deed of trust or mortgage covering real property, then the trustor or
mortgagor shall not mortgage or pledge the mortgaged premises as security for
any other indebtedness or obligations. This Note, together with all other
indebtedness secured by said deed of trust or mortgage, shall become due and
payable immediately, without notice, at the option of the Bank, (a) if said
trustor or mortgagor shall mortgage or pledge the mortgaged premises for any
other indebtedness or obligations or shall convey, assign or transfer the
mortgaged premises by deed, installment sale contract instrument, or (b) if the
title to the mortgaged premises shall become vested in any other person or party
in any manner, whatsoever, or (c) if there is any disposition (through one or
more transactions) of legal or beneficial title to a controlling interest and
said trustor or mortgagor. All payments under this Note shall be in immediately
available United States funds, without set off or counterclaim.

If the Note is signed by two or more parties (whether by all as makers or by one
or more as an accommodation party or otherwise), the obligations and
undertakings under this Note shall be that of all and any two or more jointly
and also of each severally. This Note shall bind the undersigned, and the
undersigned's respective heirs, personal representatives, successors and
assigns.

The undersigned waive(s) presentment, demand protest, notice of dishonor, notice
of demand or intent to demand, notice of acceleration or intent to accelerate,
and all other notices and agree(s) that no extension or indulgence to the
undersigned (or any of them) or release, substitute or nonenforcement of any
security, or release or substitution of any of the undersigned, any guarantor or
any other party, whether with or without notice, shall affect the obligations of
any of the undersigned. The undersigned waive(s) all defenses or right to
discharge available under Section 3-605 of the California Uniform Commercial
Code and waive(s) all other suretyship defenses or right to discharge. The
undersigned agree(s) that the Bank has the right to sell, assign, or grant
participation, or any interest, in any or all of the indebtedness, and that, in
connection with this right, but without limiting its ability to make other
disclosures to the full extent allowable, the Bank may disclose all documents
and information which the Bank now or later has relating to the undersigned or
the indebtedness, The undersigned agree(s) that the Bank may provide information
relating to the note or to the undersigned to the Bank's parent, affiliates,
subsidiaries and service providers.

                                       2



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The undersigned agree(s) to reimburse the holder or owner of this Note for any
and all costs and expenses (including without limit, court costs, legal expenses
and reasonable attorney fees, whether inside or outside counsel is used, whether
or not suit is instituted and, if suit is instituted, whether at the trial court
level, appellate level, in a bankruptcy, probate or administrative proceeding or
otherwise) incurred in collecting or attempting to collect this Note or incurred
in any other matter or proceeding relating to this Note.

The undersigned acknowledge(s) and agree(s) that there are no contrary
agreements, oral or written, establishing a term of this Note and agree(s) that
the terms and conditions of this Note may not be amended, waived or modified
except in writing signed by an officer of the Bank expressly stating that the
writing constitutes an amendment, waiver or modification of the terms of this
Note. As used in this Note, the word "undersigned" means, individually and
collectively, each maker, accommodation party, indorser and other party signing
this Note in any similar capacity. If any provision of this Note is
unenforceable in whole or part for any reason, the remaining provisions shall
continue to be effective. THIS NOTE IS MADE IN THE STATE OF CALIFORNIA AND SHALL
BE GOVERNED BY AND CONSTRUED IN ACCORDANCE WITH THE INTERNAL LAWS OF THE STATE
OF CALIFORNIA, WITHOUT REGARD TO CONFLICT OF LAWS PRINCIPLES.

The maximum interest rate shall not exceed the highest applicable usury ceiling.

THE UNDERSIGNED AND THE BANK ACKNOWLEDGE THAT THE RIGHT TO TRIAL BY JURY IS A
CONSTITUTIONAL ONE, BUT THAT IT MAY BE WAIVED, EACH PARTY, AFTER CONSULTING (OR
HAVING HAD THE OPPORTUNITY TO CONSULT) WITH COUNSEL OF THEIR CHOICE, KNOWINGLY
AND VOLUNTARILY, AND FOR THEIR MUTUAL BENEFIT, WAIVES ANY RIGHT TO TRIAL BY JURY
IN THE EVENT OF LITIGATION REGARDING THE PERFORMANCE OR ENFORCEMENT OF, OR IN
ANY WAY RELATED TO, THIS NOTE OR THE INDEBTEDNESS.

                                       3



<PAGE>

Until full and final payment of this Indebtedness and so long as Bank has any
obligation to advance funds under the Note, Borrower hereby warrants and agrees
to maintain a zero ($0.00) outstanding balance for a minimum period of thirty
(30) consecutive days each quarter following the date of this Note. See Addendum
"A" attached hereto and made a part of this Note.


                                                INITIAL HERE_________


Kinergy Marketing LLC


By:  /s/ Neil M. Koehler                       ITS:  MEMBER
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   SIGNATURE OF Neil M. Koehler                      Title





5711 NORTH WEST AVENUE        FRESNO      CA             USA            9371
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STREET ADDRESS                CITY       STATE          (COUNTRY)     ZIP CODE


<TABLE>
<S>     <C>
------------------------------------------------------------ ---------------------------------------------------------
                     For Bank Use Only                       CCAR #
------------------------- -------------------------- -----------------------------------------------------------------
Loan Officer Initials     Loan Group Name            Obligor(s) Name
ss                        Fresno Middle Market       Kinergy Marketing LLC
------------------------- -------------------------- ---------------------- ----------------- ------------------------
Loan Officer I.D. No.     Loan Group No.             Obligor #              Note #            Amount
49079                     97329                                                                    $2,000,000.00
------------------------- -------------------------- ---------------------- ----------------- ------------------------
</TABLE>


                                       4



<PAGE>

                      ADDENDUM "A" TO MASTER REVOLVING NOTE


         This Addendum "A" to Master Revolving Note (this "Addendum") is
attached to, and by this reference shall be a part of and is hereby incorporated
by this reference into that certain Master Revolving Note dated September 24,
2004 (the "Note") executed by KINERGY MARKETING LLC ("Borrower") in favor of
COMERICA BANK ("Bank") in the original principal amount of Two Million and
no/100 Dollars ($2,000,000.00) ("Note Amount"). Except as otherwise noted, the
terms not defined herein shall have the meaning set forth in the Note.

         Notwithstanding anything to the contrary contained in the Note,
Borrower and Bank agree that the provisions set forth therein shall be amended
as follows:

A.       LETTERS OF CREDIT
         -----------------

1.       Subject to availability under the Note and subject to the terms and
         conditions of the Note, Bank may, at its sole discretion from time to
         time during the term of the Note, issue or cause to be issued letters
         of credit for the account of Borrower in the aggregate outstanding face
         amount not to exceed Two Million and no/100 Dollars ($2;000,000.00);
         PROVIDED, HOWEVER, that the sum of the outstanding principal balance of
         all advances made under the Note PLUS the Letter of Credit Obligations
         shall not at any time exceed the Note Amount. All letters of credit
         shall be in a form and substance acceptable to Bank in its sole
         discretion and shall be subject to the terms and conditions of Bank's
         standard form of letter of credit application and agreement. Each
         letter of credit shall have an expiration date no later than the
         maturity date of the Note.

2.       In addition to any and all other rights and remedies available to Bank
         under or pursuant to the Note or any other documents, instruments or
         agreements contemplated hereby, Borrower acknowledges and agrees that
         (i) at any time following the occurrence and during the continuance of
         any Event of Default, and/or (ii) termination of Bank's commitment or
         obligation to make loans or advances or otherwise extend credit to or
         in favor of Borrower hereunder, in the event that and to the extent
         that there are any Letter of Credit Obligations outstanding at such
         time, upon demand of Bank, Borrower shall deliver to Bank, or cause to
         be delivered to Bank, cash collateral in an amount not less than such
         Letter of Credit Obligations, which cash collateral shall be held and
         retained by Bank as cash collateral for the repayment of such Letter of
         Credit Obligations, together with any and all other indebtedness of
         Borrower to Bank remaining unpaid, and Borrower pledges to Bank and
         grants to Bank a continuing first priority security interest in such
         cash collateral so delivered to Bank. Alternatively, Borrower shall
         cause to be delivered to Bank an irrevocable standby letter of credit
         issued in favor of Bank by a bank acceptable to Bank, in its sole
         discretion, in an amount not less than such Letter of Credit
         Obligations, and upon terms acceptable to Bank, in its sole discretion.

3.       The obligation of Borrower to immediately reimburse Bank for drawings
         made under letters of credit shall be absolute, unconditional and
         irrevocable in accordance with the terms of this Note and such letters
         of credit Borrower shall indemnify, defend, protect and hold Bank
         harmless from any loss, cost, expense, or liability, including, without
         limitation, reasonable attorneys' fees, arising out of or in connection
         with any letters of credit.

4.       If at any time for any reason, the amount of indebtedness owed by
         Borrower to Bank is greater than the aggregate amount available under
         the terms and conditions of this Note, Borrower shall immediately pay
         to Bank, in cash, the amount of such excess.

5.       "Letter of Credit Obligations" shall mean the aggregate sum of the
         undrawn amount of any letter(s) of credit issued by Bank upon the
         application of and/or for the account of Borrower, plus any unpaid
         reimbursement obligations owing by Borrower to Bank in respect of any
         such letter(s) of credit.

Kinergy Marketing LLC                       Comerica Bank

By: ________________________                By: ______________________________
      Neil M. Koehler                           Brian C. Santos
Title: MEMBER                                   Senior Vice President - Western
                                                Division


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