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                                                                  EXHIBIT 23.5


                                   April 16, 1998



Board of Directors
Northern States Power Company
414 Nicollet Mall
Minneapolis, Minnesota 55401

Ladies and Gentlemen:

     Included as Annex C to the Proxy Statement/Prospectus (the "Proxy
Statement/Prospectus") of Northern States Power Company ("NSP") and Black
Mountain Gas Company ("BMG") is our opinion letter to the Board of Directors of
BMG dated December 29, 1997 (the "Opinion Letter"), with respect to the proposed
merger of BMG with and into NSP.

     We hereby consent to the references to our firm and to the inclusion of the
Opinion Letter in Amendment No. 1 to the Registration Statement of NSP (File No.
333-49529) (of which the Proxy Statement/Prospectus forms a part).  In giving
the foregoing consent, we do not admit that we come within the category of
persons whose consent is required under Section 7 of the Securities Act of 1933,
as amended, or the rules or regulations of the Securities and Exchange
Commission thereunder, nor do we thereby admit that we are experts with respect
to any part of the Proxy Statement/Prospectus (or the Registration Statement of
which it forms a part) within the meaning of the term "experts" as used in the
Securities Act of 1933, as amended, or the rules and regulations of the
Securities and Exchange Commission thereunder.

                              Very truly yours,
                              
                              PRINCIPAL FINANCIAL SECURITIES, INC.
                              
                              
                              By:  /s/ John W. Bishop
                                  -----------------------------------
                              Managing Director
                              Everen Securities, Inc.
                              (Successor to PFS)
     
