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                                                                   Exhibit 10.15

                          EQUITY CONTRIBUTION AGREEMENT

            This EQUITY CONTRIBUTION AGREEMENT, dated as of July 20, 2000 (as
amended, amended and restated, supplemented or otherwise modified from time to
time in accordance with the terms hereof, this "Agreement"), is by and between
PPL CORPORATION, a Pennsylvania corporation ("PPL Corporation"), and PPL
MONTANA, LLC, a Delaware limited liability company ("PPL Montana").

                                    RECITALS

            A. PPL Global, LLC (formerly PP&L Global, Inc.), a Delaware limited
liability company ("PPL Global"), entered into the Asset Purchase Agreement,
dated as of October 31, 1998, and amended by Amendment No. 1 thereto dated as of
June 29, 1999 and Amendment No. 2 thereto dated as of October 29, 1999 (as so
amended, and as it may be further amended, the "MPC Asset Purchase Agreement"),
with The Montana Power Company, a Montana corporation ("MPC").

            B. Pursuant to the Instrument of Assignment, dated as of December
17, 1999, by and among PPL Global, PPL Montana and Colstrip Comm Serv, LLC, PPL
Global assigned a portion of its rights and obligations under the MPC Asset
Purchase Agreement to PPL Montana and PPL Montana assumed such rights and
obligations.

            C. PPL Montana is an indirect wholly-owned subsidiary of PPL
Corporation.

                                    AGREEMENT

            NOW THEREFORE, in consideration of the foregoing, and for other good
and valuable consideration, the receipt and adequacy of which are hereby
acknowledged, the parties hereto agree as follows:

            Section 1. Definitions. (a) Capitalized terms used but not defined
herein shall have the meanings given to such terms in Appendix A to the
Participation Agreement (as defined below).


            (b) The following terms shall have the following meanings when used
in this Agreement:


            "Assets" shall have the meaning given to such term in the MPC Asset
Purchase Agreement.

            "Bankruptcy Event" means, with respect to any Person: (1) the
commencement by such Person of a voluntary case or other proceeding seeking
relief under 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 the application by such Person for,
or consent by such Person to, the appointment of a trustee, receiver,
liquidator, custodian or other similar official of it or any substantial part of
its property; (2) the consent by
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such Person to, or the failure by such Person 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; (3) the filing
by such Person of an answer admitting the material allegations of a petition
filed against it in any such proceeding; or (4) the commencement of an
involuntary case or other proceeding against such Person seeking (a)
liquidation, reorganization or other relief with respect to such Person or its
debts under the Bankruptcy Code or any bankruptcy, insolvency or other similar
law now or hereafter in effect, (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 such
Person.

            "Colstrip 1, 2 and 3 Transmission Assets" shall have the meaning
given to such term in the MPC Asset Purchase Agreement.

            "Equity Contribution" shall mean a cash capital contribution or any
other cash payment to PPL Montana required to be made by PPL Corporation (or any
subsidiary thereof) to PPL Montana in accordance with Section 2.

            "Operative Agreements" shall have the meaning given to such term in
the MPC Asset Purchase Agreement.

            "Operative Documents" shall mean the documents, agreements and
instruments included in the definition thereof in each of the Participation
Agreements.

            "Participation Agreement" shall mean each of the Participation
Agreements, dated as of July 13, 2000, by and among PPL Montana, the Owner
Lessor named therein, Wilmington Trust Company, in its individual capacity and
as Lessor Manager, the Owner Participant named therein, the Lease Indenture
Trustee and The Chase Manhattan Bank, as Pass Through Trustee.

            "Portland Asset Purchase Agreement" shall mean the Asset Purchase
Agreement, dated as of November 1, 1998, by and between PPL Global and Portland
General Electric Company.

            "Portland Closing Date" shall have the meaning given to such term in
the MPC Asset Purchase Agreement.

            "Portland Payment Amount" shall have the meaning given to such term
in the MPC Asset Purchase Agreement.

            "Transaction Documents" shall mean, collectively, the Operative
Agreements, the Operative Documents and the Portland Asset Purchase Agreement.

            "Triggering Obligations" shall mean the obligations of PPL Montana
described in clauses (a) and (b) of Section 2.
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            Section 2. Equity Contributions. PPL Corporation shall make Equity
Contributions to PPL Montana as follows:

            (a) if (i) PPL Corporation receives written notice by or on behalf
of PPL Montana or any other Person entitled to exercise rights hereunder that
PPL Montana has become obligated to pay the Portland Payment Amount to MPC on
the Portland Closing Date pursuant to Section 1.05(b)(ii) of the MPC Asset
Purchase Agreement, and (ii) PPL Montana has not consented in writing to the
related purchase of assets by PPL Global from Portland, then PPL Corporation
shall make, or shall cause one of its subsidiaries to make, an Equity
Contribution to PPL Montana, at least one Business Day prior to the Portland
Closing Date, in an amount equal to the Portland Payment Amount; and

            (b) if PPL Montana becomes obligated to purchase the Colstrip 1, 2
and 3 Transmission Assets from MPC pursuant to Section 1.10(f)(i) of the MPC
Asset Purchase Agreement, PPL Corporation shall make, or shall cause one of its
subsidiaries to make, an Equity Contribution to PPL Montana, at least one
Business Day prior to the closing date for such acquisition, in the amount of
$97,100,000 (or such lesser amount as may be agreed upon between PPL Montana and
MPC as the purchase price for the Colstrip 1, 2 and 3 Transmission Assets).

            Section 3. Obligations Unconditional; Waivers. (a) The obligations
of PPL Corporation under Section 2 shall be absolute, unconditional and
irrevocable under any and all circumstances, and shall be performed by PPL
Corporation regardless of:

                    (i) the existence of any indebtedness owing by PPL Montana,
          any member of PPL Montana or any Affiliate thereof to PPL Corporation
          or of any setoff, abatement, reduction, limitation, impairment,
          termination, counterclaim, recoupment, defense or other right or claim
          which PPL Corporation may have against PPL Montana, any member of PPL
          Montana, any Affiliate thereof or any other Person;

                    (ii) the occurrence of a Bankruptcy Event of PPL Montana,
          any member of PPL Montana, any Affiliate thereof or any other Person
          or the pendency against PPL Montana, any member of PPL Montana, any
          Affiliate thereof or any other Person of any case, suit or proceeding
          under the Bankruptcy Code;

                    (iii) the invalidity, irregularity or unenforceability of,
          or any change in or amendment to, any of the Transaction Documents; or

                    (iv) any other circumstance whatsoever which might otherwise
          constitute an excuse for nonperformance of the obligations of PPL
          Corporation under Section 2, whether similar or dissimilar to any of
          the circumstances herein specified.

            (b) PPL Corporation hereby unconditionally:

                    (i) waives any act, omission or thing or delay to do any act
          or thing which might in any manner or to any extent vary the risk of
          PPL Corporation or which might otherwise operate as a discharge to PPL
          Corporation;
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                    (ii) agrees that this Agreement shall remain in full force
          and effect without regard to, and shall not be affected or impaired
          by, any invalidity, irregularity or unenforceability in whole or in
          part of any of the Transaction Documents which may now or hereafter be
          caused or imposed in any manner whatsoever;

                    (iii) agrees that no failure or delay on the part of PPL
          Montana, MPC or any other Person in exercising any right, power or
          privilege hereunder or under any other Transaction Document and no
          course of dealing between PPL Corporation on the one hand, and PPL
          Montana, any member of PPL Montana, any Affiliate thereof or MPC, on
          the other hand, shall operate as a waiver thereof, nor shall any
          single or partial exercise of any right, power or privilege hereunder
          preclude any other or further exercise thereof or the exercise of any
          other right, power or privilege hereunder;

                    (iv) agrees that the rights and remedies herein provided are
          cumulative and not exclusive of any rights or remedies which PPL
          Montana, any member of PPL Montana or any Affiliate thereof would
          otherwise have;

                    (v) agrees that this Agreement shall be discharged only by
          complete performance and payment in full of the obligations contained
          herein and that PPL Corporation shall have no right to withhold or
          set-off against any payments due for any reason; and

                    (vi) agrees to make such Equity Contributions as and when
          required hereunder regardless of whether, at the time, PPL Montana is
          able to issue any membership interests or other equity interests, or
          any indebtedness, to PPL Corporation in respect of the making by PPL
          Corporation of Equity Contributions hereunder.

            Section 4. [Reserved]

            Section 5. Modification of Obligations. PPL Corporation agrees that
PPL Montana and MPC may, at any time and from time to time, without the consent
of or notice to PPL Corporation, without incurring responsibility to PPL
Corporation and without impairing or releasing any of PPL Montana's rights or
any of the obligations of PPL Corporation under this Agreement:

            (a) change the amount, manner, place or terms of payment or change
or extend the time of payment or renew or alter the Triggering Obligations in
any manner or enter into or amend in any manner any agreement relating to the
Triggering Obligations;

            (b) sell, exchange, release or otherwise deal with any property by
whomsoever at any time pledged or mortgaged to secure, or howsoever securing,
any of the Triggering Obligations;

            (c) release anyone liable in any manner for payment or collection of
the Triggering Obligations; and

            (d) exercise or refrain from exercising any rights against the other
Person.
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            Section 6. Representations and Warranties: PPL Corporation hereby
represents and warrants that:

            (a) it is a corporation duly organized, validly existing and in good
standing under the laws of the State of Pennsylvania, is duly licensed or
qualified to transact business and in good standing in each jurisdiction in
which the failure so to qualify would have a material adverse effect on its
ability to perform its obligations under this Agreement, and has the corporate
power and authority to enter into and perform its obligations under this
Agreement;

            (b) this Agreement has been duly authorized, executed and delivered
by all necessary corporate action by PPL Corporation and, assuming the due
authorization, execution and delivery by each other party hereto, this Agreement
constitutes the legal, valid and binding obligation of PPL Corporation,
enforceable against it in accordance with its terms, except as the same may be
limited by bankruptcy, insolvency, fraudulent conveyance, reorganization,
arrangement, moratorium or other laws relating to or affecting the rights of
creditors generally and by general principles of equity;

            (c) the execution, delivery and performance by PPL Corporation of
this Agreement, the consummation by PPL Corporation of the transactions
contemplated hereby and compliance by PPL Corporation with the terms and
provisions hereof, do not and will not (i) contravene any Applicable Law binding
on PPL Corporation or its property, or its organizational documents, or (ii)
constitute a default by PPL Corporation under, or result in the creation of any
Lien upon the property of PPL Corporation under, any indenture, mortgage or
other material contract, agreement or instrument to which PPL Corporation is a
party or by which PPL Corporation or any of its property is bound; and

            (d) no authorization, determination or approval or other action by,
and no notice to or filing or registration with, any Governmental Entity or
under any Applicable Law is required for the due execution, delivery or
performance by PPL Corporation of this Agreement.

            Section 7. Notices. Unless otherwise expressly specified or
permitted by the terms hereof, all communications and notices provided for
herein shall be in writing or by a telecommunications device capable of creating
a written record, and any such notice shall become effective (a) upon personal
delivery thereof, including by overnight mail or courier service, (b) in the
case of notice by United States mail, certified or registered, postage prepaid,
return receipt requested, upon receipt thereof, or (c) in the case of notice by
such a telecommunications device, upon transmission thereof, provided such
transmission is promptly confirmed by either of the methods set forth in clauses
(a) or (b) above, in each case addressed to each party hereto at its address set
forth below or, in the case of any such party hereto, at such other address as
such party may from time to time designate by written notice to the other
parties hereto:

                PPL Corporation:    PPL Corporation
                                    2 North 9th Street
                                    Allentown, PA 18101
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                                    Attn: James E. Abel, Vice President-Finance
                                    and Treasurer
                                    Telephone No.:  (610) 774-5987
                                    Telecopy No.:  (610) 774-5106

                PPL Montana:        PPL Montana, LLC
                                    303 North Broadway, Suite 400
                                    Billings, MT 59101
                                    Attn: David B. Kinnard, Vice President and
                                    General Counsel
                                    Telephone No.:  (406) 869-5103
                                    Facsimile No.:  (406) 869-5149

A copy of all notices provided for herein shall be sent by the party giving such
notice to each of the other parties hereto.

            Section 8. Reinstatement. This Agreement shall continue to be
effective or be reinstated, as the case may be, if at any time any amount
received by PPL Montana hereunder or pursuant hereto is rescinded or must
otherwise be restored or returned by PPL Montana upon the insolvency,
bankruptcy, dissolution, liquidation or reorganization of PPL Corporation, PPL
Montana, any member of PPL Montana or any Affiliate thereof or upon the
appointment of any intervenor or conservator of, or trustee or similar official
for, PPL Corporation, PPL Montana, any member of PPL Montana or any Affiliate
thereof, or any substantial part of PPL Corporation's, PPL Montana's, any such
member's or any such Affiliate's assets, or upon the entry of an order by any
court avoiding the payment of such amount, or otherwise, all as though such
payments had not been made.

            Section 9. Termination. Subject to Section 8, PPL Corporation's
obligations under Section 2 shall terminate upon the earliest to occur of (a)
the payment in full of the Triggering Obligations, (b) the payment in full of
each of the Lessor Notes and (c) the termination of the MPC Asset Purchase
Agreement.

            Section 10. Amendments. No term, covenant, agreement or condition of
this Agreement may be terminated, amended or compliance therewith waived (either
generally or in a particular instance, retroactively or prospectively) except by
an instrument or instruments in writing executed by each party hereto.

            Section 11. Successors and Assigns. This Agreement shall be binding
upon and shall inure to the benefit of, and shall be enforceable by, the parties
hereto and their respective successors and assigns as permitted by and in
accordance with the terms hereof. PPL Corporation may not assign or otherwise
transfer any of its rights or obligations under this Agreement without the
written consent of PPL Montana.

            Section 12. Survival. All warranties, representations, indemnities
and covenants made by any party hereto, herein or in any certificate or other
instrument delivered by any such party or on the behalf of any such party under
this Agreement, shall be considered to have been relied upon by each other party
hereto and shall survive the consummation of the
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transactions contemplated hereby and the other Transaction Documents regardless
of any investigation made by any such party or on behalf of any such party.

            Section 13. Counterparts. This Agreement may be executed in any
number of counterparts, each executed counterpart constituting an original but
all together only one agreement.

            Section 14. Headings. The headings of the sections of this Agreement
are inserted for purposes of convenience only and shall not be construed to
affect the meaning or construction of any of the provisions hereof.

            Section 15. Severability. If any provision hereof shall be invalid,
illegal or unenforceable under Applicable Law, the validity, legality and
enforceability of the remaining provisions hereof shall not be affected or
impaired thereby.

            Section 16. Governing Law. This Agreement has been delivered in the
State of New York and shall be in all respects governed by and construed in
accordance with the laws of the State of New York including all matters of
construction, validity and performance without giving effect to the conflicts of
laws provisions thereof except New York General Obligations Law Section 5-1401.

            Section 17. Waiver of Jury Trial. TO THE EXTENT PERMITTED BY
APPLICABLE LAW, EACH OF THE PARTIES HERETO HEREBY IRREVOCABLY WAIVES THE RIGHT
TO DEMAND A TRIAL BY JURY IN ANY SUCH SUIT, ACTION OR OTHER PROCEEDING ARISING
OUT OF THIS AGREEMENT OR THE SUBJECT MATTER HEREOF OR ANY OF THE TRANSACTIONS
CONTEMPLATED HEREBY BROUGHT BY ANY OF THE PARTIES HERETO OR THEIR SUCCESSORS OR
ASSIGNS.

            Section 18. Entire Agreement. This Agreement, together with any
other agreement executed in connection herewith, is intended by the parties as a
final expression of their agreement as to the matters covered hereby and is
intended as a complete and exclusive statement of the terms and conditions
thereof.

            Section 19. Nature of Obligation. The obligations of PPL Corporation
hereunder shall not be deemed to be a guarantee of indebtedness of PPL Montana
or any other Person.
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            IN WITNESS WHEREOF, the parties hereto have caused this Agreement to
be duly executed and delivered as of the date first written above.


                        PPL CORPORATION

                        By:     /s/ James E. Abel
                               ------------------------------
                               Name:  James E. Abel
                               Title: Vice President - Finance and Treasurer


                        PPL MONTANA, LLC

                        By:     /s/ Paul A. Farr
                               ------------------------------
                               Name:  Paul A. Farr
                               Title: Vice President & CFO