<PAGE>

                                                                   Exhibit 10(n)



                        CONSTELLATION ENERGY GROUP, INC.
                        --------------------------------


                           SUPPLEMENTAL PENSION PLAN
                           -------------------------



                           Effective January 1, 2000
<PAGE>

                               TABLE OF CONTENTS

<TABLE>
<CAPTION>

                                                       Page No.
<S>                                                      <C>
1.   Objective                                             1

2.   Definitions                                           1

3.   Plan Administration                                   4

4.   Eligibility                                           4

5.   Supplemental Pension Benefit                          5
     (a)  Generally                                        5
     (b)  Retirement benefits                              5
          (i)  Eligibility for retirement benefits         5
          (ii) Computation of retirement benefits          5
          (iii)Form of payout of retirement benefits       6
          (iv) Amount, timing, and source of monthly
               retirement benefit payout                   7
          (v)  Amount, timing, and source of lump sum
               retirement benefit payout                   7
          (vi) Death of participant entitled to lump
               sum payout                                  8
     (c)  Entitlement to benefit upon happening of
          certain events                                   8
          (i)  Computation of gross accrued benefit        8
          (ii) Computation of net accrued benefit          9
          (iii)Satisfaction of requirements                9
          (iv) Other events                                10
               (1)  Change in control                      10
               (2)  Plan amendment                         10
               (3)  Involuntary Demotion, Termination
                    From Employment With Constellation
                    Energy Group, or eligibility
                    withdrawal without Cause               11
          (v)  Form of benefit payout                      11
          (vi) Amount, timing and source of benefit
               payout                                      11
          (vii)Death of participant entitled to lump
               sum payout                                  12

6.   Supplemental Survivor Annuity Benefit                 12
     (a)  Survivor annuity benefit                         12
          (i)  Eligibility for survivor annuity benefit    12
          (ii) Computation of survivor annuity benefit     13
          (iii)Form of payout of survivor annuity
               benefits                                    15
</TABLE>
<PAGE>

                                      -2-

<TABLE>
<CAPTION>
<S>                                                       <C>
          (iv) Amount, timing, and source of monthly
               survivor annuity benefit payout             15
          (v)  Amount, timing, and source of lump sum
               survivor benefit payout                     15
          (vi) Death of surviving spouse entitled to
               lump sum payout.                            16

7.   Miscellaneous                                         16
</TABLE>
<PAGE>

                        CONSTELLATION ENERGY GROUP, INC.
                        --------------------------------

                           SUPPLEMENTAL PENSION PLAN
                           -------------------------


1.   Objective.  The objective of this Plan is to enhance the benefits provided
     ---------
     to certain officers and key employees of Constellation Energy Group and its
     subsidiaries in order to attract and retain talented executive personnel.

2.   Definitions.  All words beginning with an initial capital letter and not
     -----------
     otherwise defined herein shall have the meaning set forth in the Pension
     Plan.   All singular terms defined in this Plan will include the plural and
     vice versa. As used herein, the following terms will have the meaning
     ----------
     specified below:

     "Annual Base Salary" means an amount determined by adding the monthly base
     rate of pay amounts (i.e., the types of such pay that are includable in the
     computation of Pension Plan benefits)earned over the twelve calendar months
     immediately preceding the month that includes the date of the computation.

     "Average Incentive Award" (or "Average Award") means generally the product
     of the percentage equal to an average of the two highest of the
     participant's five immediately prior year award percentages earned under
     Constellation Energy Group's Executive Annual Incentive Plan, Constellation
     Energy Group's Senior Management Annual Incentive Plan and/or other
     Incentive Awards Program multiplied by the participant's annualized base
     rate of pay amount (i.e., the types of such pay that are includable in the
     computation of Pension Plan benefits) in effect at the end of the prior
     year.

     "Benefit Start Date" means the date as of which the participant's benefits,
     if any, under this Plan commence.

     "Cause" means the participant's (a) failure to comply with Constellation
     Energy Group policy, (b) deliberate and continual refusal to satisfactorily
     perform employment duties on substantially a full-time basis, (c)
     deliberate and continual refusal to act in accordance with any specific
     instructions of a majority of Constellation Energy Group's Board of
     Directors, (d) disclosure, without the consent of a
<PAGE>

                                      -2-

     majority of Constellation Energy Group's Board of Directors, of
     confidential information or trade secrets concerning Constellation Energy
     Group which could be materially damaging to Constellation Energy Group, or
     (e) deliberate misconduct which could be materially damaging to
     Constellation Energy Group without reasonable good faith belief by the
     participant that such conduct was in the best interest of Constellation
     Energy Group.

     "Change in Control" means (a) the purchase or acquisition by any person,
     entity or group of persons, (within the meaning of Section 13(d) or 14(d)
     of the Securities Exchange Act of 1934 (the "Exchange Act"), or any
     comparable successor provisions), of beneficial ownership (within the
     meaning of Rule 13d-3 promulgated under the Exchange Act) of 20 percent or
     more of either the outstanding shares of common stock of Constellation
     Energy Group or the combined voting power of Constellation Energy Group's
     then outstanding shares of voting securities entitled to a vote generally,
     or (b) the consummation of, following the approval by the stockholders of
     Constellation Energy Group of a reorganization, merger, or consolidation of
     Constellation Energy Group, in each case, with respect to which persons who
     were stockholders of Constellation Energy Group immediately prior to such
     reorganization, merger or consolidation do not, immediately thereafter, own
     more than 50 percent of the combined voting power entitled to vote
     generally in the election of directors of the reorganized, merged or
     consolidated entity's then outstanding securities, or (c) a liquidation or
     dissolution of Constellation Energy Group or the sale of substantially all
     of its assets, or (d) a change of more than one-half of the members of the
     Board of Directors of Constellation Energy Group within a 90-day period for
     reasons other than the death, disability, or retirement of such members.

     "Committee" means the Committee on Management of the Board of Directors of
     Constellation Energy Group.

     "Constellation Energy Group" means Constellation Energy Group, Inc., a
     Maryland corporation, or its successor.

     "Constellation Energy Group's Executive Annual Incentive Plan" means such
     plan or other incentive plan or arrangement designated in writing by the
     Plan Administrator.
<PAGE>

                                      -3-

     "Constellation Energy Group's Senior Management Annual Incentive Plan"
     means such plan or other incentive plan or arrangement designated in
     writing by the Plan Administrator.

     "Demotion" means a transfer to a position with Constellation Energy Group
     or a subsidiary of Constellation Energy Group that either (a) is
     substantially below the position in which the participant was employed on
     the date of transfer, or (b) results in a substantial reduction in pay when
     compared to the participant's pay on the date of the transfer.  Whether a
     position is a substantially below another position shall be determined in
     the reasonable discretion of the Committee, with reference to factors
     including whether the participant retains principal responsibility for a
     department or division, and whether the participant remains eligible for
     the perquisites enjoyed by the participant before the position change.

     "Early Receipt Reduction Factor" means 100% less .25% for each month that
     the participant is less than age 62 on the participant's Benefit Start
     Date.

     "Interest Rate" means the rate equal to the average monthly 30-year
     Treasury bond rate for the second calendar quarter preceding the
     computation date, less 50 basis points.

     "Internal Revenue Code Limitations" means the limitations under Sections
     415 and/or 401(a)(17) of the Internal Revenue Code.

     "LTD Plan" means the Constellation Energy Group, Inc. Disability Insurance
     Plan as may be amended from time to time, or any successor plan.

     "Mortality Table" means the mortality table used to convert annuities to
     lump sums in the Pension Plan.

     "Other Incentive Awards Program" means the program(s) designated in writing
     by the Plan Administrator applicable to certain employees that provides
     awards; but includes only the types of awards that are includable in the
     computation of Pension Plan benefits.

     "Pension Plan" means the Pension Plan of Constellation Energy Group, Inc.
     as may be amended from time to time, or any successor plan.
<PAGE>

                                      -4-

     "Plan" means this Constellation Energy Group, Inc. Supplemental Pension
     Plan.

     "Plan Administrator" means, as set forth in Section 3, the Committee.

     "Rabbi Trust" means the trust adopted by Constellation Energy Group
     pursuant to the Grantor Trust Agreement Dated as of January 1, 2001,
     between Constellation Energy Group and Citibank, N.A.

     "Survivor Annuity Percentage" means 50%, unless the participant elects in
     the timing and manner established by the Plan Administrator, a higher
     percentage (in multiples of 5% to a total percentage not to exceed 100%).

     "Termination From Employment With Constellation Energy Group" means a
     participant's separation from service with Constellation Energy Group or a
     subsidiary of Constellation Energy Group; however, a participant's
     retirement, disability, or transfer of employment to or from a subsidiary
     of Constellation Energy Group shall not constitute a Termination From
     Employment With Constellation Energy Group.

3.   Plan Administration.  The Committee is the Plan Administrator and has sole
     -------------------
     authority (except as specified otherwise herein) to interpret the Plan and,
     in general, to make all other determinations advisable for the
     administration of the Plan to achieve its stated objective.  Appeals of
     written decisions by the Plan Administrator may be made to the Board of
     Directors of Constellation Energy Group.  Decisions by the Board shall be
     final and not subject to further appeal.  The Plan Administrator shall have
     the power to delegate all or any part of its duties to one or more
     designees, and to withdraw such authority, by written designation.

4.   Eligibility.  The officers or key employees of Constellation Energy Group
     -----------
     or its subsidiaries designated in Appendix A are participants under the
     Plan.  Participation shall continue until such designation is withdrawn at
     the discretion and by written order of the Plan Administrator, provided,
     however, that such withdrawal may not be made for benefits provided
     pursuant to Sections 5 and 6 with respect to a participant who has
     satisfied the eligibility requirements to retire (as set forth in Section
     5(b)(i)).  Notwithstanding the foregoing, any participant while
<PAGE>

                                      -5-

     classified as disabled under the LTD Plan shall continue to participate in
     this Plan while classified as disabled and, for purposes of the
     supplemental pension benefit provided by this Plan, while classified as
     disabled, shall be deemed to continue to accrue Credited Service until no
     later than his/her Normal Retirement Date.

5.   Supplemental Pension Benefit.
     -----------------------------

     (a)  Generally.  A participant shall be eligible for supplemental pension
          ---------
          benefits and supplemental survivor annuity benefits under this Plan
          only if the participant's supplemental pension benefits under this
          Plan are greater than the supplemental pension benefits computed under
          the Executive Benefits Plan based on the participant's age, service,
          and eligible compensation on the date as of which benefits become
          payable.

     (b)  Retirement benefits.
          -------------------

          (i)  Eligibility for retirement benefits. A participant shall be
               -----------------------------------
               eligible to retire under this Plan on or after the participant's
               Normal Retirement Date, or on the first day of any month
               preceding his/her Normal Retirement Date, if on his/her Severance
               From Service Date and while a participant he/she has attained (1)
               age 55 and has accumulated at least 10 years of Credited Service;
               or (2) age 60 and has accumulated at least one year of Credited
               Service.

          (ii) Computation of retirement benefits.  A participant who is
               ----------------------------------
               eligible to retire under this Plan will be entitled to
               supplemental pension retirement benefits under this Plan, which
               will be calculated as set forth below on the participant's
               Benefit Start Date:

               (1)  add the Annual Base Salary and the Average Incentive Award,

               (2)  divide the sum by 12,

               (3)  multiply this dollar amount by the appropriate percentage,
                    determined as follows:  Chairman of the Board of
                    Constellation Energy Group - 60%; all other
<PAGE>

                                      -6-

                    participants (by completed years of Credited Service) 1
                    through 9 - 3% per year; 10 through 19 - 40%; 20 through
                    24 -45%; 25 through 29 - 50%; and 30 or more - 55%,

               (4)  multiply this dollar amount by the Early Receipt Reduction
                    Factor; provided, however, if the participant is age 62 or
                    older, such factor shall be one (1),

               (5)  subtract from this dollar amount the charges relating to
                    coverage for a preretirement survivor annuity in excess of
                    50%, and for a post-retirement survivor annuity in excess of
                    50%, and

               (6)  subtract from the remainder the net amount payable to the
                    participant under the Pension Plan on the participant's
                    Benefit Start Date, assuming a 50% spousal joint and
                    survivor annuity for a married participant(if the
                    participant is not eligible to commence monthly Pension Plan
                    payments on the participant's Benefit Start Date, the
                    participant's benefit will be unreduced for Pension Plan
                    payments until the date the participant is first eligible to
                    commence monthly Pension Plan payments), or, if the
                    participant elects a lump sum under the PEP provisions of
                    the Pension Plan, the monthly amount that would have been
                    payable under the Pension Plan as a life annuity for a
                    single participant or as a 50% spousal joint and survivor
                    annuity for a married participant, as of the Benefit Start
                    Date under this Plan.

         (iii) Form of payout of retirement benefits.  Each participant entitled
               -------------------------------------
               to supplemental pension retirement benefits will receive his/her
               supplemental pension retirement benefits payout in the form of a
               monthly payment, unless the participant makes a valid election to
               receive his/her supplemental pension retirement benefits payout
               in the form of a lump sum.

               A participant may elect to receive his/her supplemental pension
               retirement benefits payout in the form of a lump sum by
               submitting to the Plan
<PAGE>

                                      -7-

               Administrator a signed Lump Sum Election Form. The Form must be
               received by the Plan Administrator before the beginning of the
               calendar year during which the participant's Severance From
               Service Date occurs. The election may be revoked at any time
               before the beginning of the calendar year during which the
               participant's Severance From Service Date occurs, by submitting
               to the Plan Administrator a signed Lump Sum Revocation Form.

          (iv) Amount, timing, and source of monthly retirement benefit payout.
               ---------------------------------------------------------------
               A participant entitled to monthly supplemental pension retirement
               benefits will receive monthly payments equal to the amount
               determined under paragraph (b)(ii).  Such payments shall commence
               effective with the first of the month following the participant's
               Severance From Service Date.  If such participant receives (or
               would have received but for the Internal Revenue Code
               Limitations) cost of living adjustment(s) under the Pension Plan,
               the monthly payments hereunder will be automatically increased
               based on the percentage of, and at the same time as, such
               adjustment(s).  Monthly payments hereunder shall permanently
               cease upon the death of the participant, effective with the
               monthly payment for the month following the month of the
               participant's death.  Monthly payments hereunder shall be made in
               accordance with the provisions of the Rabbi Trust and, to the
               extent not paid under the terms of the Rabbi Trust, from general
               corporate assets.

          (v)  Amount, timing, and source of lump sum retirement benefit payout.
               ----------------------------------------------------------------
               A participant entitled to a lump sum supplemental pension
               retirement benefit will receive a lump sum payment.  This lump
               sum payment will be calculated by a certified actuary and will be
               equal to the present value of an immediate annuity including the
               estimated present value of post-retirement supplemental survivor
               annuity benefits described in Section 6, and reflecting the
               present value of any deferred Pension Plan payments using (1) the
               supplemental pension retirement benefit amount calculated under
               paragraph (b)(ii), which is expressed as a monthly amount, (2)
               the Interest Rate computed on the
<PAGE>

                                      -8-

               participant's Benefit Start Date, and (3) the Mortality Table.
               Such lump sum payment shall be made within 60 days after the
               participant's Retirement Date. The lump sum payment shall be made
               in accordance with the provisions of the Rabbi Trust and, to the
               extent not paid under the terms of the Rabbi Trust, from general
               corporate assets. A participant who receives a lump sum payment
               shall not be entitled to any cost of living or other pension
               payment adjustments or to post-retirement survivor annuity
               coverage under the Plan.

          (vi) Death of participant entitled to lump sum payout.  In the event
               ------------------------------------------------
               of the death of a participant after his/her Severance From
               Service Date and before the participant receives the lump sum
               payment under paragraph (b)(v), such lump sum payment shall be
               made to the participant's surviving spouse (as defined in Section
               6(i)).  The lump sum payment shall be the same amount and made at
               the same time and from the same sources as set forth in paragraph
               (b)(v).  If there is no surviving spouse at the date of the
               participant's death, no payments shall be made pursuant to
               Sections 5 or 6.  A surviving spouse who receives a lump sum
               benefit under this paragraph (b)(vi) shall not be entitled to any
               cost of living or other pension payment adjustments or to post-
               retirement survivor annuity coverage under the Plan.


      (c)      Entitlement to benefit upon happening of certain events.
               -------------------------------------------------------
          (i)  Computation of gross accrued benefit.  The computation of the
               ------------------------------------
               gross accrued supplemental pension benefit for a participant as
               of the date of the computation will be made as follows:

               (1)  add the Annual Base Salary and the Average Incentive Award,

               (2)  divide the sum by 12, and

               (3)  multiply this dollar amount by the appropriate percentage,
                    determined as follows:  Chairman of the Board of
<PAGE>

                                      -9-

                    Constellation Energy Group - 60%; all other participants (by
                    completed years of Credited Service as of the date of the
                    computation) 1 through 9 - 3% per year; 10 through 19 - 40%;
                    20 through 24 - 45%; 25 through 29 - 50%; and 30 or more -
                    55%.

         (ii)  Computation of net accrued benefit. The computation of the net
               ----------------------------------
               accrued supplemental pension benefit for a participant as of the
               date of the computation will be made by subtracting from the
               gross accrued benefit determined under paragraph (c)(i) the
               amount of the participant's Gross Pension under the Pension Plan
               determined as of the date of the computation and assuming that
               monthly payments of such Gross Pension begin on the first of the
               month after the later of reaching age 62 or the date of the
               computation. If the participant is not eligible for payment of a
               Gross Pension under the Pension Plan, the participant's Accrued
               Gross Pension determined as of the date of the computation shall
               be substituted for the Gross Pension described above, with the
               appropriate reduction for early receipt applied as if the
               participant were eligible to begin payment of his Accrued Gross
               Pension on the first of the month after the later of reaching age
               62 or the date of the computation.

         (iii) Satisfaction of requirements. A participant who has satisfied
               ----------------------------
               the age and Credited Service requirements set forth in Section
               5(b)(i) while eligible as set forth in Section 4, but who the
               Committee determines does not retire under the Plan due to
               Demotion, Termination From Employment With Constellation Energy
               Group, or the withdrawal of a participant's eligibility to
               participate under Section 5,  shall be entitled to his/her net
               accrued supplemental pension  benefit.  The effective date of the
               Demotion, Termination From Employment With Constellation Energy
               Group, or eligibility withdrawal event shall be the date of such
               Demotion, Termination From Employment With Constellation Energy
               Group, or eligibility withdrawal.

         (iv)  Other events.  A participant, regardless of his/her age and years
               ------------
               of Credited Service, shall
<PAGE>

                                     -10-

               be entitled to his/her net accrued supplemental pension benefit
               upon the happening of any of the following entitlement events,
               but only if such entitlement event occurs while a participant and
               before a participant retires under this Plan:

               (1)  Change in Control.  A Change in Control, followed within two
                    -----------------
                    years by the participant's Demotion, a participant's
                    Termination From Employment With Constellation Energy Group,
                    or the withdrawal of the participant's eligibility to
                    participate under the Plan, is an entitlement event.  The
                    effective date of the entitlement event shall be the date of
                    the Demotion, Termination From Employment With Constellation
                    Energy Group, or eligibility withdrawal.

               (2)  Plan amendment.  A Plan amendment that has the effect of
                    --------------
                    reducing a participant's gross accrued supplemental pension
                    benefit is an entitlement event.  In determining whether
                    such a reduction has occurred, the participant's gross
                    accrued supplemental pension benefit calculated on the day
                    immediately preceding the effective date of the amendment
                    shall be compared to the participant's gross accrued
                    supplemental pension benefit calculated on the effective
                    date of the amendment.  An amendment that has the effect of
                    reducing future benefit accruals is not an entitlement
                    event.  It is intended that an entitlement event under this
                    paragraph (c)(iv)(2) will occur only with respect to those
                    amendments that are substantially similar to amendments that
                    are prohibited by Internal Revenue Code section 411(d)(6)
                    with respect to qualified pension plans.  The effective date
                    of the entitlement event shall be the effective date of the
                    Plan amendment.
<PAGE>

                                     -11-

               (3)  Involuntary Demotion, Termination From Employment With
                    ------------------------------------------------------
                    Constellation Energy Group, or eligibility withdrawal
                    -----------------------------------------------------
                    without Cause.  A participant's involuntary Demotion or
                    -------------
                    involuntary Termination From Employment With Constellation
                    Energy Group without Cause, or the withdrawal of a
                    participant's eligibility to participate under Sections 5 or
                    6 of the Plan without Cause, is an entitlement event.  The
                    effective date of the entitlement event shall be the
                    effective date of the participant's involuntary Demotion or
                    involuntary Termination From Employment With Constellation
                    Energy Group without Cause, or the eligibility withdrawal
                    without Cause.

          (v)  Form of benefit payout. Each participant entitled to a payout
               ----------------------
               under this paragraph (c) will receive such payout in the form of
               a lump sum payment.

          (vi) Amount, timing, and source of benefit payout.  A participant
               --------------------------------------------
               entitled to a payout of his/her net accrued benefit, as a result
               of the occurrence of an event described in paragraphs (c)(iii),
               (c)(iv)(1), (2), or (3) will be entitled to a lump sum benefit.
               This lump sum benefit will be calculated by a certified actuary
               as the present value, determined as of the date of payment, of an
               annuity beginning at age 62  (or the participant's actual age, if
               the participant is older than age 62 on the date the lump sum
               benefit is payable), including the estimated present value of
               post-retirement survivor annuity benefits described in Section 7,
               using (1) the net accrued benefit amount calculated under
               paragraph (d)(ii) on the effective date of the entitlement event,
               which is expressed as a monthly amount, (2) the Interest Rate
               computed on the date the lump sum benefit is payable, and (3) the
               Mortality Table.  The lump sum benefit shall be payable as of the
               participant's Severance From service Date, and shall be made
               within 60 days after such date in accordance with the provisions
               of the Rabbi Trust and, to the extent not paid under the terms of
               the Rabbi Trust, from general corporate assets.  A participant
               who receives a lump sum benefit under this paragraph (c)(vi)
               shall not be entitled to
<PAGE>

                                     -12-

               any cost of living or other pension payment adjustments or to
               preretirement or post-retirement survivor annuity coverage.

         (vii) Death of participant entitled to lump sum payout.  In the event
               ------------------------------------------------
               of the death of a participant after the occurrence of an event
               described in paragraphs (c)(iii), (c)(iv)(1), (2), or (3) and
               before the participant receives the lump sum payment under
               paragraph (c)(v), such lump sum payment shall be made to the
               participant's surviving spouse (as defined in Section 6(i)).  The
               lump sum payment will be calculated by a certified actuary and
               will be equal to 100% of the lump sum that would have been paid
               to the participant under paragraph (vi), as of the date on which
               the lump sum is payable under this paragraph (vii), provided that
               the participant's date of death is on or after his/her Severance
               From Service Date.  If the participant's date of death is before
               his/her Severance From Service Date, 50% shall be substituted for
               100% in the preceding sentence. The lump sum benefit shall be
               payable as of the earlier of the participant's Severance From
               Service Date or date of death, and shall be made within 60 days
               after such date in accordance with the provisions of the Rabbi
               Trust and, to the extent not paid under the terms of the Rabbi
               Trust, from general corporate assets.  If there is no surviving
               spouse at the date of the participant's death, no payments shall
               be made pursuant to Sections 5 or 6.  A surviving spouse who
               receives a lump sum benefit under this paragraph (c) (vii) shall
               not be entitled to any cost of living or other pension payment
               adjustments or to preretirement or post-retirement survivor
               annuity coverage under the Plan.

6.   Supplemental Survivor Annuity Benefit.
     -------------------------------------

     (a) Survivor annuity benefit.
         ------------------------

         (i)   Eligibility for survivor annuity benefit.  Following the death of
               ----------------------------------------
               a participant who is fully vested under the Pension Plan, a
               supplemental survivor annuity may be paid to the participant's
               surviving spouse until the death of that spouse, using the
               Survivor Annuity Percentage. The
<PAGE>

                                     -13-

               participant will not bear the cost of up to a 50% survivor
               annuity benefit, but will bear the cost of a survivor annuity
               benefit in excess of 50%. For purposes of this Section 6(a), a
               participant's surviving spouse is the individual married to the
               participant on the date of the participant's death. If there is
               no surviving spouse, or if the participant or the participant's
               spouse previously received or is entitled to receive either a
               lump sum payment under Section 5, or a benefit under the Senior
               Executive Supplemental Plan, no supplemental survivor annuity
               will be payable.

         (ii)  Computation of survivor annuity benefit.  The amount of the
               ---------------------------------------
               supplemental survivor annuity will be determined as follows:

               (1)  if the participant's Benefit Start Date occurred prior to
                    the date of death:

                    (a)  begin with the monthly pension benefit (under Section
                         5(b) of this Plan) that the participant was receiving
                         prior to the date of death, and

                    (b)  multiply this dollar amount by the Survivor Annuity
                         Percentage.

               (2)  otherwise:

                    (a)  Unless the participant elected the alternative in-
                         service death benefit in section (b) below:

                         (1) begin with the monthly Early Retirement pension
                         benefit (under both the Pension Plan and Section 5(b)
                         of this Plan) to which the participant would have been
                         entitled to receive if:

                              the participant had been retired at the later of
                              age 60 or his/her actual age on the date of death
                              for purposes of computing the Early Receipt
                              Reduction Factor,

                         (2) multiply this dollar amount by the Survivor Annuity
                         Percentage ,
<PAGE>

                                     -14-

                         (3)  subtract from the product the net amount, if any,
                         of the survivor annuity provided on behalf of the
                         participant under the Pension Plan if the participant
                         is participating in the Traditional Pension Plan, or
                         the monthly annuity that would have been provided to
                         the participant's spouse assuming that he or she had
                         been designated as the participant's beneficiary and
                         had chosen to receive a survivor benefit in the form of
                         a monthly annuity, if the participant is participating
                         in the PEP, and

                         (4)  subtract from this dollar amount the charges
                         relating to coverage (under both the Pension Plan and
                         this Plan) for a preretirement survivor annuity in
                         excess of 50%.

                   (b)   If the participant was a participant in the Pension
                         Equity Plan option of the Pension Plan and elected this
                         alternative in-service death benefit by December 31 of
                         the year prior to his/her death or during the 2001
                         initial election period established by the Plan
                         Administrator

                         (1)  calculate the benefit under the Constellation
                              Energy Group Benefits Restoration Plan that would
                              have been payable to the surviving spouse if the
                              participant were a participant in that plan and
                         (2)  that dollar amount will be paid to the surviving
                              spouse only in the form of a lump sum from this
                              Plan.


         (iii) Form of payout of survivor annuity benefits. Unless the
               -------------------------------------------
               participant made a valid election by December 31 of the year
               prior to his/her death or during the 2001 initial election period
               established by the Plan Administrator, to have the survivor
               benefits paid in a lump sum, each
<PAGE>

                                     -15-

               surviving spouse entitled to a supplemental survivor annuity
               benefit will receive his/her survivor annuity benefit payout in
               the form of a monthly payment.

          (iv) Amount, timing, and source of monthly survivor annuity benefit
               --------------------------------------------------------------
               payout.  A surviving spouse entitled to monthly supplemental
               ------
               survivor annuity benefits will receive a monthly payment equal to
               the amount determined under (ii) above.  Such payments shall
               commence effective with the first day of the month following the
               month of the participant's death.  If such surviving spouse
               receives (or would have received but for the Internal Revenue
               Code Limitations) cost of living adjustment(s) under the Pension
               Plan, the monthly payments hereunder will be automatically
               increased based on the percentage of, and at the same time as,
               such adjustment(s).  Monthly payments hereunder shall permanently
               cease upon the death of the surviving spouse, effective with the
               monthly payment for the month following the month of the
               surviving spouse's death.  Monthly payments hereunder shall be
               made in accordance with the provisions of the Rabbi Trust and, to
               the extent not paid under the terms of the Rabbi Trust, from
               general corporate assets.

          (v)  Amount, timing, and source of lump sum survivor benefit payout. A
               --------------------------------------------------------------
               surviving spouse entitled to a lump sum supplemental survivor
               benefit will receive a lump sum payment.  This lump sum payment
               will be calculated by a certified actuary and will be equal to
               the present value of an immediate annuity. Such lump sum payment
               shall be made within 60 days after the participant's death.  The
               lump sum payment shall be made in accordance with the provisions
               of the Rabbi Trust and, to the extent not paid under the terms of
               the Rabbi Trust, from general corporate assets.  A surviving
               spouse who receives a lump sum payment shall not be entitled to
               any cost of living or other pension payment adjustments.

          (vi) Death of surviving spouse entitled to lump sum payout.  In the
               -----------------------------------------------------
               event of the death of a surviving spouse before the spouse
               receives the lump sum
<PAGE>

                                     -16-

               payment under section 6(a)(v) no payment shall be made.

7.   Miscellaneous.  None of the benefits provided under this Plan shall be
     -------------
     subject to alienation or assignment by any participant or beneficiary nor
     shall any of them be subject to attachment or garnishment or other legal
     process except (i) to the extent specially mandated and directed by
     applicable State or Federal statute; or (ii) as requested by the
     participant or beneficiary to satisfy income tax withholding or liability.

     This Plan may be amended from time to time, or suspended or terminated at
     any time, provided, however, that no amendment or termination shall reduce
     any previously accrued supplemental pension benefit under this Plan or
     impair the rights of any participant or beneficiary entitled to receive
     current or future payment hereunder at the time of such action.  All
     amendments to this Plan which would increase or decrease the compensation
     of any Officer of Constellation Energy Group, either directly or
     indirectly, must be approved by the Board of Directors.  All other
     permissible amendments may be made at the written direction of the
     Committee. Notwithstanding anything else in this Plan to the contrary, the
     Constellation Energy Group Board of Directors may authorize a Participant
     to be eligible for benefits or may increase benefit payments.

     Participation in this Plan shall not constitute a contract of employment
     between Constellation Energy Group and any person and shall not be deemed
     to be consideration for, or a condition of, continued employment of any
     person.

     The Plan, notwithstanding the creation of the Rabbi Trust, is intended to
     be unfunded for purposes of Title I of the Employee Retirement Income
     Security Act of 1974. Constellation Energy Group shall make contributions
     to the Rabbi Trust in accordance with the terms of the Rabbi Trust.  Any
     funds which may be invested and any assets which may be held to provide
     benefits under this Plan shall continue for all purposes to be a part of
     the general funds and assets of Constellation Energy Group and no person
     other than Constellation Energy Group shall by virtue of the provisions of
     this Plan have any interest in such funds and assets.  To the extent that
     any person acquires a right to receive payments from Constellation Energy
     Group under this Plan, such rights shall be no greater than the right of
     any unsecured general creditor of Constellation Energy Group.
<PAGE>

                                     -17-

     In the event Constellation Energy Group becomes a party to a merger,
     consolidation, sale of substantially all of its assets or any other
     corporate reorganization in which Constellation Energy Group will not be
     the surviving corporation or in which the holders of the common stock of
     Constellation Energy Group will receive securities of another corporation
     (in any such case, the "New Company"), then the New Company shall assume
     the rights and obligations of Constellation Energy Group under this Plan.

     This Plan shall be governed in all respects by Maryland law.