Note Modification Agreement

This agreement is dated as of August 18, 2005 (the "Agreement Date"), by and
between MGE Energy, Inc. (the "Borrower") and JPMorgan Chase Bank, N.A. (the
"Bank"). The provisions of this agreement are effective on the date that this
agreement has been executed by all of the signers and delivered to the Bank (the
"Effective Date").

WHEREAS, the Borrower executed a Line of Credit Note as evidence of indebtedness
in the original face amount of Sixty Million and 00/100 Dollars
($60,000,000.00), dated September 29, 2004 owing by the Borrower to the Bank, as
same may have been amended or modified from time to time (the "Note"), which
Note has at all times been, and is now, continuously and without interruption
outstanding in favor of the Bank; and,

WHEREAS, the Borrower has requested and the Bank has agreed that the Note be
modified to the limited extent as hereinafter set forth;

NOW THEREFORE, in mutual consideration of the agreements contained herein and
for other good and valuable consideration, the parties agree as follows:

1. ACCURACY OF RECITALS. The Borrower acknowledges the accuracy of the Recitals
stated above.

2. MODIFICATION OF NOTE.

2.1 From and after the Effective Date, the provision in the Note captioned
“Promise to Pay” is hereby amended as follows:  The date on which the entire
balance of unpaid principal plus accrued interest shall be due and payable
immediately is hereby changed from September 30, 2005 to January 31, 2006.

2.2 Each of the Related Documents is modified to provide that it shall be a
default or an event of default thereunder if the Borrower shall fail to comply
with any of the covenants of the Borrower herein or if any representation or
warranty by the Borrower or by any guarantor herein is materially incomplete,
incorrect, or misleading as of the date hereof. As used in this agreement, the
"Related Documents" shall include the Note and all loan agreements, credit
agreements, reimbursement agreements, security agreements, mortgages, deeds of
trust, pledge agreements, assignments, guaranties, or any other instrument or
document executed in connection with the Note or in connection with any other
obligations of the Borrower to the Bank.

2.3 Each reference in the Related Documents to any of the Related Documents
shall be a reference to such document as modified herein.

3. RATIFICATION OF RELATED DOCUMENTS AND COLLATERAL. The Related Documents are
ratified and reaffirmed by the Borrower and shall remain in full force and
effect as they may be modified herein. All real or personal property described
as security in the Related Documents shall remain as security for the Note and
the obligations of the Borrower in the Related Documents.

4. BORROWER REPRESENTATIONS AND WARRANTIES. The Borrower represents and warrants
to the Bank:

4.1 No default or event of default under any of the Related Documents as
modified hereby, nor any event, that, with the giving of notice or the passage
of time or both, would be a default or an event of default under the Related
Documents as modified herein has occurred and is continuing.

4.2 There has been no material adverse change in the financial conditions of the
Borrower or any other person whose financial statement has been delivered to the
Bank in connection with the Note from the most recent financial statement
received by the Bank.

4.3 Each and all representations and warranties of the Borrower in the Related
Documents are accurate on the date hereof.

4.4 The Borrower has no claims, counterclaims, defenses, or setoffs with respect
to the loan evidenced by the Note or with respect to the Related Documents as
modified herein.

4.5 The Note and the Related Documents as modified herein are the legal, valid,
and binding obligations of the Borrower, enforceable against the Borrower in
accordance with their terms.

4.6 The Borrower, other than any Borrower who is a natural person, is validly
existing under the laws of the

State of its formation or organization. The Borrower has the requisite power and
authority to execute and deliver this agreement and to perform the obligations
described in the Related Documents as modified herein. The execution and
delivery of this agreement and the performance of the obligations described in
the Related Documents as modified herein have been duly authorized by all
requisite action by or on behalf of the Borrower. This agreement has been duly
executed and delivered by or on behalf of the Borrower.

5. BORROWER COVENANTS. The Borrower covenants with the Bank:

5.1 The Borrower shall execute, deliver, and provide to the Bank such additional
agreements, documents, and instruments as reasonably required by the Bank to
effectuate the intent of this agreement.

5.2 The Borrower fully, finally, and forever releases and discharges the Bank
and its successors, assigns, directors, officers, employees, agents, and
representatives from any and all causes of action, claims, debts, demands, and
liabilities, of whatever kind or nature, in law or equity, of the Borrower,
whether now known or unknown to the Borrower, (i) in respect of the loan
evidenced by the Note and the Related Documents, or of the actions or omissions
of the Bank in any manner related to the loan evidenced by the Note or the
Related Documents and (ii) arising from events occurring prior to the date of
this agreement.

5.3 The Borrower shall pay to the Bank:

5.3.1 All the internal and external costs and expenses incurred by the Bank in
connection with this agreement (including, without limitation, inside and
outside attorneys, appraisal, appraisal review, processing, title, filing, and
recording costs, expenses, and fees).

6. EXECUTION AND DELIVERY OF AGREEMENT BY THE BANK. The Bank shall not be bound
by this agreement until (i) the Bank has executed this agreement and (ii) the
Borrower performed all of the obligations of the Borrower under this agreement
to be performed contemporaneously with the execution and delivery of this
agreement.

7. INTEGRATION, ENTIRE AGREEMENT, CHANGE, DISCHARGE, TERMINATION, OR WAIVER. The
Note and the Related Documents as modified herein contain the complete
understanding and agreement of the Borrower and the Bank in respect of the loan
and supersede all prior representations, warranties, agreements, arrangements,
understandings, and negotiations. No provision of the Note or the Related
Documents as modified herein may be changed, discharged, supplemented,
terminated, or waived except in a writing signed by the party against whom it is
being enforced.

8. GOVERNING LAW AND VENUE. This agreement is delivered in the State of
Wisconsin and governed by Wisconsin law (without giving effect to its laws of
conflicts). The Borrower agrees that any legal action or proceeding with respect
to any of its obligations under the Note or this agreement may be brought by the
Bank in any state or federal court located in the State of Wisconsin, as the
Bank in its sole discretion may elect. By the execution and delivery of this
agreement, the Borrower submits to and accepts, for itself and in respect of its
property, generally and unconditionally, the non-exclusive jurisdiction of those
courts. The Borrower waives any claim that the State of Wisconsin is not a
convenient forum or the proper venue for any such suit, action or proceeding.
This agreement binds the Borrower and its successors, and benefits the Bank, its
successors and assigns. The Borrower shall not, however, have the right to
assign the Borrower's rights under this agreement or any interest therein,
without the prior written consent of the Bank.

9. COUNTERPART EXECUTION. This agreement may be executed in multiple
counterparts, each of which, when so executed, shall be deemed an original, but
all such counterparts, taken together, shall constitute one and the same
agreement.

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10. NOT A NOVATION. This agreement is a modification only and not a novation. In
addition to all amounts hereafter due under the Note and the Related Documents
as they may be modified herein, all accrued interest evidenced by the Note being
modified by this agreement and all accrued amounts due and payable under the
Related Documents shall continue to be due and payable until paid.  Except for
the above-quoted modification(s), the Note, any Related Documents, and all the
terms and conditions thereof, shall be and remain in full force and effect with
the changes herein deemed to be incorporated therein. This agreement is to be
considered attached to the Note and made a part thereof. This agreement shall
not release or affect the liability of any guarantor, surety or endorser of the
Note or release any owner of collateral securing the Note. The validity,
priority and enforceability of the Note shall not be impaired hereby. References
to the Related Documents and to other agreements shall not affect or impair the
absolute and unconditional obligation of the Borrower to pay the principal and
interest on the Note when due. The Bank reserves all rights against all parties
to the Note.

Borrower:

Address: 133 South Blair Street

MGE Energy, Inc.

Madison, WI 43703

By: /s/ Jeffrey C. Newman, VP & Treasurer

Date September 2, 2005

BANK’S ACCEPTANCE

The foregoing agreement is hereby agreed to and acknowledged.

Bank:

JPMorgan Chase Bank, N.A.

By /s/ David N. Slezewski Vice President

Date Signed: September 2, 2005