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                                                                   EXHIBIT 10.13

                                PROMISSORY NOTE

$71,110,000                                                    December 19, 2000

                                                                Atlanta, Georgia

          FOR VALUE RECEIVED, SOUTHERN ENERGY PEAKER, LLC, a Delaware limited
liability company (the "Maker"), hereby unconditionally promises to pay SOUTHERN
ENERGY MID-ATLANTIC, LLC (the "Holder"), at the offices of the Holder located at
1155 Perimeter Center West, Atlanta, Georgia 30338, or at such other place
within the United States as shall be designated from time to time by the Holder,
on December 30, 2028, the principal amount of SEVENTY ONE MILLION, ONE HUNDRED
TEN THOUSAND AND NO/100 DOLLARS ($71,110,000.00) (the "Loan"), or such lesser
principal amount as may then constitute the aggregate unpaid balance of the Loan
made by the Holder to the Maker pursuant to this Note, in lawful money of the
United States of America in federal or other immediately available funds.

          The Maker also unconditionally promises to pay interest on the unpaid
principal amount of the Loan for each day from the date of disbursement until
such principal amount is paid in full, at a rate of 10% per annum (the "Interest
Rate").  Interest calculated hereunder shall be due and payable semiannually, in
arrears, on December 30 and June 30 of each calendar year beginning June 30,
2001.  Any amount payable hereunder not paid when due (whether at maturity, by
acceleration or otherwise) shall bear interest thereafter, payable on demand, at
a rate per annum equal to the 12% (the "Default Rate").  All computations of
interest shall be made on the basis of a year of 360 days, and paid, in each
case, for the actual number of days elapsed (including the first day but
excluding the last day).  Nothing contained in this Note shall be deemed to
establish or require the payment of a rate of interest in excess of the maximum
rate permitted by any applicable law.  In the event that any rate of interest
required to be paid hereunder exceeds the maximum rate permitted by applicable
law, such interest rate shall be reduced to the extent necessary to comply with
applicable law, and any interest amounts paid by Maker to Holder in excess of
such applicable rate shall be held in trust by the Holder for the benefit of the
Maker, to be remitted to Maker.

          The Maker shall make each payment of principal of, and interest on,
the Loan hereunder not later than 12:00 Noon (New York time) on the day when
due.  Payments received after 12:00 Noon (New York time) shall be deemed to have
been received on the following Business Day (and such additional day shall be
included in any related computation of interest).  For the purposes of this
Note, "Business Day" shall mean any day other than a Saturday, a Sunday, or a
day on which commercial banking institutions are authorized or required by law,
regulation or executive order to be closed in New York, New York.

          If any amount payable hereunder is due on a day which is not a
Business Day, payment thereof shall be made on the next succeeding Business Day
with the same effect as if made on the date on which such payment was due,
unless such Business Day falls in another calendar month, in which case the date
for payment thereof shall be the immediately preceding
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Business Day. If the date, for any payment of principal is extended by operation
of law, interest thereon shall be payable for such extended time.

          Presentment for payment, demand, protest and notice of demand, notice
of dishonor, notice of non-payment and all other notices or demands in
connection with the delivery, acceptance, performance, default or endorsement of
this Note are hereby waived by the Maker.  No delay or omission on the part of
Holder in exercising any right hereunder shall operate as a waiver of such right
or any other right under this Note.  A waiver of any right or remedy on any one
occasion shall not be construed as a bar to or waiver of any right or remedy on
any future occasion.

          The Maker shall be entitled, without the consent of the Holder and
without paying any penalty or premium therefor, to prepay up $2,539,643 per year
on a cumulative basis.  Such prepayment shall only be made out of the operating
cash flow of the Maker.

          The Maker's obligation to repay this Note shall be unconditional and
absolute, without setoff, regardless of any rights, claims or defenses that the
Maker might have against the Holder or any other party.

          Any and all payments by the Maker under this Note shall be made free
and clear of and without deduction for any and all Covered Taxes, except to the
extent such deduction or withholding is required by law.  If the Maker shall be
required by law to withhold or deduct any Taxes from or in respect of any sum
payable under this Note, (i) if such Taxes are Covered Taxes, the sum payable
shall be increased as may be necessary so that after making all required
deductions for Covered Taxes (including deductions applicable to additional sums
payable hereunder) the Holder receives an amount equal to the sum it would have
received had no such deductions been made, (ii) the Maker shall make such
deductions and (iii) the Maker shall pay the full amount deducted to the
relevant taxation authority or other authority in accordance with applicable
law.

          In addition, the Maker agrees to pay any present or future stamp or
documentary taxes or any other excise or property taxes, charges or similar
levies that arise under applicable law from any payment made under this Note or
from the execution or delivery or otherwise with respect to this Note
(hereinafter referred to as "Other Taxes").

          The Maker shall indemnify the Holder and the Owner Lessor as third
party beneficiary for the full amount of Covered Taxes and Other Taxes
(including, without limitation, any Covered Taxes or Other Taxes imposed by any
jurisdiction on amounts payable hereunder) paid by the Holder or any liability
(including penalties, interest and expenses) arising therefrom or with respect
thereto such that, after making all such payments, the Holder receives such
amounts as it would have received had no such Covered Taxes, Other Taxes or
liabilities been imposed on the Holder.  The Holder shall give written notice to
the Maker no later than 90 days after it learns of the imposition of any Covered
Taxes or Other Taxes.  Payments by the Maker pursuant to this paragraph shall be
made within 30 days from the date the Holder makes written demand therefor
(submitted through the Holder), which demand shall be accompanied by a
certificate describing in reasonable detail the basis thereof.  The Holder
agrees that if it receives a

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final tax credit or tax deduction with respect to any amount paid by the Maker
pursuant to this paragraph, the Holder shall reimburse the Maker to the extent
it has actually benefited from such tax credit or tax deduction (as determined
by the Holder in its good faith judgment) in an amount equal to the lesser of
(i) the benefit of such credit or deduction of net expenses incurred by the
Holder in obtaining such benefit and (ii) the related amount paid by the Maker
to the Holder. The obligations of the Holder under the preceding sentence shall
survive the termination of this Note.

          Within 30 days after the date of any payment of Covered Taxes or Other
Taxes by the Maker, the Maker shall furnish to the Holder, at the Holder's
address referred to above, the original or a certified copy of a receipt
evidencing payment thereof.  The Maker shall compensate the Holder for all
reasonable losses and expenses sustained by it as a result of any failure by the
Maker to so furnish such copy of such receipt.

          For the purposes of this Note, "Taxes" shall mean all fees (including
receipts, franchise, rental, turn over, excise, sales taxes, use taxes, stamp
taxes, value-added taxes, ad valorem taxes and property taxes (personal and
real, tangible and intangible), but excluding all income taxes), licenses,
levies, exports, duties, recording charges or fees, assessments, withholdings
and other charges and impositions of any nature, plus all related interest,
penalties, fines and additions to tax, now or hereafter imposed by any federal,
state, local or foreign government or other taxing authority.

          For the purposes of this Note, "Covered Taxes"  shall mean all Taxes
imposed by any Governmental Authority or any political subdivision or taxing
authority thereof or therein that would not have been incurred but for making by
Holder of the loan evidenced hereunder or any payment contemplated hereunder.
"Governmental Authority" shall mean any nation or government, any state,
provincial or other political subdivision thereof and any entity exercising
executive, legislative, judicial, regulatory or administrative functions of or
pertaining to government.

          The agreements and obligations of the Maker relating to Covered Taxes
and Other Taxes shall survive the payment in full of principal and interest
under this Note.  In the event that (i) the Maker fails to pay principal
hereunder when the same becomes payable, whether by scheduled maturity or
required prepayment or acceleration or otherwise, (ii) the Maker fails to pay
interest or any other amount hereunder when the same becomes due and payable and
such failure shall continue for five (5) Business Days, (iii) the Maker fails to
perform or observe any term, covenant or condition on its part to be performed
or observed hereunder when required to be performed or observed, (iv) the Maker
(a) commences a voluntary case or other proceeding seeking relief under Title 11
of the United States Bankruptcy Code of 1978, as amended from time to time, 11
U.S.C. (S) 101 et seq. (the "Bankruptcy Code") or liquidation, reorganization or
other relief with respect to itself or its debts under any bankruptcy,
insolvency or other similar law now or hereafter in effect, or applies for or
consents to the appointment of a trustee, receiver, liquidator, custodian or
other similar official of it or any substantial part of its property, or (b)
consents to, or fails to controvert in a timely manner, any such relief or the
appointment of or taking possession by any such official in any voluntary case
or other proceeding commenced against it, or (c) files an answer admitting the
material allegations of a petition filed against it in

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any such proceeding, or (d) makes a general assignment for the benefit of
creditors, or (v) an involuntary case or other proceeding shall be commenced
against the Maker seeking (a) liquidation, reorganization or other relief with
respect to it or its debts under Title 11 of the Bankruptcy Code or any
bankruptcy, insolvency or other similar law now or hereafter in effect, or (b)
the appointment of a trustee, receiver, liquidator, custodian or other similar
official with respect to it or any substantial part of its property, or (c) the
winding-up or liquidation of the Maker and such involuntary case or other
proceeding shall remain undismissed and unstayed for a period of 60 days, then
Holder shall, by notice to the Maker, take any of the following actions, without
prejudice to the rights of the Holder to enforce its claims against the Maker:
(A) declare the principal of and any accrued interest in respect of this Note
and all other amounts payable hereunder to be, whereupon the same shall become,
forthwith due and payable without presentment, demand, protest or other notice
of any kind, all of which are hereby waived by the Maker and (B) exercise any
other remedies available at law or in equity.

          The Maker hereby agrees to pay all costs and expenses incurred in
collecting the Loan and other obligations of the Maker hereunder or in enforcing
or attempting to enforce any of the Holder's rights hereunder, including, but
not limited to, reasonable attorneys' fees and expenses if collected by or
through an attorney, whether or not suit is filed.

          No failure to exercise and no delay in exercising on the part of the
Holder of any right, power or privilege hereunder shall operate as a waiver
thereof, nor shall any single or partial exercise of any such right, power or
privilege preclude any other or further exercise thereof, or the exercise of any
other right, power or privilege.  The rights and remedies herein provided are
cumulative and not exclusive of any rights or remedies provided by law.

          The Maker shall not assign or otherwise transfer all or any part of
its rights or obligations hereunder without the prior written consent of the
Holder.

          Any provision hereof that is prohibited or unenforceable in any
jurisdiction shall, as to such jurisdiction, be ineffective to the extent of
such prohibition or unenforceability  without invalidating the remaining
provisions hereof and without affecting the validity or enforceability of any
provision in any other jurisdiction.

          THE MAKER HEREBY SEVERALLY, IRREVOCABLY AND UNCONDITIONALLY SUBMITS
FOR ITSELF AND ITS PROPERTY IN ANY LEGAL ACTION OR PROCEEDING RELATING TO THIS
NOTE, OR FOR RECOGNITION AND ENFORCEMENT OF ANY JUDGMENT IN RESPECT HEREOF, TO
THE NON-EXCLUSIVE GENERAL JURISDICTION OF THE COURTS OF THE STATE OF NEW YORK,
LOCATED IN NEW YORK, NEW YORK, AND THE COURTS OF THE UNITED STATES OF AMERICA
FOR THE SOUTHERN DISTRICT OF NEW YORK, AND CONSENTS THAT ANY SUCH ACTION OR
PROCEEDING MAY BE BROUGHT IN SUCH COURTS, AND WAIVES TO THE FULLEST EXTENT
PERMITTED BY LAW ANY OBJECTION THAT IT MAY NOW OR HEREAFTER HAVE TO THE VENUE OF
ANY SUCH ACTION OR PROCEEDING IN ANY SUCH COURT OR THAT SUCH ACTION OR
PROCEEDING WAS BROUGHT IN AN INCONVENIENT COURT AND AGREES NOT TO PLEAD OR CLAIM
THE SAME.

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          This Term Note shall be governed by, and construed in accordance with,
the laws of the State of  New York.


                             SOUTHERN ENERGY PEAKER, LLC
                             By: /s/ Gary J. Kubik
                                 -----------------------------------
                             Name:  Gary J. Kubik
                                    --------------------------------
                             Title: Vice President, Chief Financial
                                    --------------------------------
                                    Officer and Treasurer
                                    --------------------------------

Attest:

By: /s/ Michelle H. Ancosky
    ---------------------------
   Name: Michelle H. Ancosky
        -----------------------
   Title: Secretary
         ----------------------

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