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                                                                    Exhibit 4.14

                              CERTIFICATE OF MERGER
                                       OF
                RELIANT ENERGY POWER GENERATION MERGER SUB, INC.,
                             A DELAWARE CORPORATION,
                                      INTO
                           ORION POWER HOLDINGS, INC.,
                             A DELAWARE CORPORATION

         ORION POWER HOLDINGS, INC., a Delaware corporation (the "SURVIVING
CORPORATION"), in compliance with the requirements of the General Corporation
Law of the State of Delaware, as amended (the "DGCL"), and desiring to effect a
merger of RELIANT ENERGY POWER GENERATION MERGER SUB, INC., a Delaware
corporation (the "MERGING CORPORATION," and collectively with the Surviving
Corporation, the "CONSTITUENT CORPORATIONS"), with and into the Surviving
Corporation, and acting by its duly authorized officer, DOES HEREBY CERTIFY
that:

         FIRST: The name and state of incorporation of each of the Constituent
Corporations of the merger are as follows:

<TABLE>
<CAPTION>
NAME                                        STATE OF INCORPORATION
----                                        ----------------------
<S>                                         <C>
ORION POWER HOLDINGS, INC.                  Delaware
RELIANT ENERGY POWER GENERATION
MERGER SUB, INC.                            Delaware
</TABLE>

         SECOND: An agreement and plan of merger has been approved, adopted,
certified, executed and acknowledged by each of the Constituent Corporations in
accordance with the requirements of Section 251(c) of the DGCL;

         THIRD: The name of the Surviving Corporation of the merger is ORION
POWER HOLDINGS, INC. At the effective time of the merger, the name of the
Surviving Corporation will be changed to RELIANT ENERGY POWER GENERATION MERGER
SUB, INC.;

         FOURTH: The Certificate of Incorporation of the Surviving Corporation
is hereby amended in its entirety to read as set forth on EXHIBIT A attached
hereto, and as so amended, such Certificate of Incorporation shall be the
Certificate of Incorporation of the Surviving Corporation until such time as it
may be amended in accordance with applicable law and the provisions thereof;

         FIFTH: The executed agreement and plan of merger is on file at an
office of the Surviving Corporation, the address of which is Seven East Redwood
Street, 10th Floor, Baltimore, Maryland 21202;

         SIXTH: A copy of the agreement and plan of merger will be furnished by
the Surviving Corporation, on request and without cost, to any stockholder of
any Constituent Corporation; and

         SEVENTH: This Certificate of Merger shall be effective on its filing
with the Secretary of State of the State of Delaware.

         Dated: February 19, 2002

                                          ORION POWER HOLDINGS, INC.,
                                                a Delaware corporation
                                          By: /s/ W. THADDEUS MILLER
                                              Name: W. THADDEUS MILLER
                                              Title: EXECUTIVE VICE PRESIDENT
                                                     AND CHIEF LEGAL OFFICER

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                                                                       EXHIBIT A

                          CERTIFICATE OF INCORPORATION

                                       OF

                RELIANT ENERGY POWER GENERATION MERGER SUB, INC.

         FIRST: The name of the Corporation is Reliant Energy Power Generation
Merger Sub, Inc. (hereinafter the "Company").

         SECOND: The address of the registered office of the Company in the
State of Delaware is 9 East Loockerman Street, City of Dover 19901, County of
Kent, and the name of the registered agent of the Company at such address is
National Registered Agents, Inc.

         THIRD: The purpose of the Company is to engage in any lawful act or
activity for which corporations may be organized under the General Corporation
Law of the State of Delaware (the "DGCL").

         FOURTH: The total number of shares of all classes of stock which the
Company shall have authority to issue is 1,000 shares of common stock, par value
$1.00 per share ("Common Stock"). Each share of Common Stock shall entitle the
holder thereof to one vote on each matter voted upon by the stockholders of the
Company. Shares of Common Stock may be issued for such consideration and for
such corporate purposes as the Board of Directors of the Company (the "Board of
Directors") may from time to time determine.

         FIFTH: The following provisions are inserted for the management of the
business and the conduct of the affairs of the Company, and for further
definition, limitation, and regulation of the powers of the Company and of its
directors and stockholders.

         (1)      The business and affairs of the Company shall be managed by or
                  under the direction of the Board of Directors except as
                  otherwise provided by law.

         (2)      The number of directors of the Company shall be as from time
                  to time fixed by, or in the manner provided in, the Bylaws of
                  the Company (the "Bylaws"). Election of directors need not be
                  by written ballot unless the Bylaws so provide.

         (3)      In addition to the powers and authority hereinbefore or by
                  statute expressly conferred upon them, the directors are
                  hereby authorized to exercise all such powers and do all such
                  acts and things as may be exercised or done by the Company,
                  subject, nevertheless, to the provisions of the statutes of
                  the State of Delaware, this Certificate of Incorporation, and
                  any Bylaws adopted by the stockholders; provided, however,
                  that no Bylaws thereafter adopted by the stockholders shall
                  invalidate any prior act of the directors which would have
                  been valid if such Bylaws had not been adopted.

         (4)      In furtherance of, and not in limitation of, the powers
                  conferred by statute, the Board of Directors is expressly
                  authorized to make, alter, amend, change, add to, or repeal
                  the Bylaws of the Company.

         SIXTH: Meetings of the stockholders may be held within or without the
State of Delaware, as the Bylaws may provide. The books of the Company may be
kept (subject to any provision contained in the statutes) outside the State of
Delaware at such place or places as may be designated from time to time by the
Board of Directors or in the Bylaws.

         SEVENTH: No director of the Company shall be personally liable to the

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Company or any of its stockholders for monetary damages for breach of fiduciary
duty as a director of the Company; provided, however, that this Article Seventh
shall not eliminate or limit the liability of such a director

         (1)      for any breach of such director's duty of loyalty to the
                  Company or its stockholders,

         (2)      for acts or omissions not in good faith or which involve
                  intentional misconduct or a knowing violation of law,

         (3)      under Section 174 of the DGCL, as the same exists or as such
                  provision may hereafter be amended, supplemented or replaced,
                  or

         (4)      for any transactions from which such director derived an
                  improper personal benefit.

         If the DGCL is amended after the filing of this Certificate of
Incorporation to authorize corporate action further eliminating or limiting the
personal liability of directors, then the liability of a director of the
Company, in addition to the limitation on personal liability provided herein,
shall be limited to the fullest extent permitted by such law, as so amended. Any
repeal or modification of this Article Seventh by the stockholders of the
Company shall be prospective only, and shall not adversely affect any limitation
on the personal liability of a director of the Company existing at the time of
such repeal or modification.

         EIGHTH: Whenever a compromise or arrangement is proposed between the
Company and its creditors or any class of them and/or between the Company and
its stockholders or any class of them, any court of equitable jurisdiction
within the State of Delaware may, on the application in a summary way of the
Company or of any creditor or stockholder thereof or on the application of any
receiver or receivers appointed for the Company under Section 291 of the DGCL or
on the application of trustees in dissolution or of any receiver or receivers
appointed for the Company under Section 279 of the DGCL order a meeting of the
creditors or class of creditors, and/or of the stockholders or class of
stockholders of the Company, as the case may be, to be summoned in such manner
as the said court directs. If a majority in number representing three fourths in
value of the creditors or class of creditors, and/or of the stockholders or
class of stockholders of the Company, as the case may be, agree to any
compromise or arrangement and to any reorganization of the Company as
consequence of such compromise or arrangement, the said compromise or
arrangement and the said reorganization shall, if sanctioned by the court to
which the said application has been made, be binding on all the creditors or
class of creditors, and/or on all the stockholders or class of stockholders, of
the Company, as the case may be, and also on the Company.

         NINTH: The Company reserves the right to amend, alter, change, or
repeal any provision contained in this Certificate of Incorporation, in the
manner now or hereafter prescribed by the laws of the State of Delaware. All
rights herein conferred are granted subject to this reservation.

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                                    AMENDMENT
                                       OF
                          CERTIFICATE OF INCORPORATION
                                       OF
                RELIANT ENERGY POWER GENERATION MERGER SUB, INC.,
                             A DELAWARE CORPORATION
                   (TO BE RENAMED ORION POWER HOLDINGS, INC.)

         Reliant Energy Power Generation Merger Sub, Inc. ("Company"), a
corporation organized and existing under and by virtue of the General
Corporation Law of the State of Delaware ("DGCL"), acting by its duly authorized
officer does hereby certify that:

         1.       The name of the Company is Reliant Energy Power Generation
                  Merger Sub, Inc.

         2.       The Board of Directors of the Company duly adopted a
                  resolution proposing and declaring advisable the amendment to
                  the Certificate of Incorporation as described herein, and the
                  Company's sole stockholder has duly adopted such amendment,
                  all in accordance with the provisions of Sections 141, 228 and
                  242 of the DGCL.

         3.       The amendment to Certificate of Incorporation effected by this
                  amendment changes the name of the Company to Orion Power
                  Holdings, Inc.

         4.       The Certificate of Incorporation is hereby amended by deleting
                  Article First thereof and replacing it in its entirety with
                  the following Article First:

         FIRST: The name of the Corporation is Orion Power Holdings, Inc.
(hereinafter the "Company").

         IN WITNESS WHEREOF, the Company has caused this certificate to be
executed this 19TH day of February, 2002.

                                  RELIANT ENERGY POWER GENERATION MERGER
                                  SUB, INC.

                                  By: /s/ CURTIS A. MORGAN
                                      -----------------------------------
                                      Name: Curtis A. Morgan
                                      Title: President