Exhibit 99.04

    New NSP Utility Sub Summarized Pro Forma Information The following summary of unaudited pro forma financial information for New NSP Utility Sub adjusts the historical financial statements of NSP after the transfer of ownership. Upon completion of the merger, all NSP-Minnesota utility assets (other than investments in and assets of subsidiaries) and liabilities associated with the assets will be transferred to New NSP Utility Sub.

    The unaudited pro forma balance sheet information at Dec. 31, 1999, assumes the merger had been completed on Dec. 31, 1999. The unaudited pro forma income statement information assumes the merger had been completed on Jan.1, 1997, the beginning of the earliest period presented.

    The unaudited summarized pro forma financial information does not necessarily indicate what New NSP Utility Sub's financial position or operating results would have been if the merger had been completed on the assumed completion dates and does not necessarily indicate future operating results of New NSP Utility Sub.

NEW NSP UTILITY SUB—Notes To Unaudited Pro Forma Condensed Financial Statements

1.

Just before or at the time the merger is completed, NSP will contribute all of its NSP-Minnesota utility assets (other than investments in and assets of subsidiaries) to a newly formed, wholly owned utility operating subsidiary, New NSP Utility Sub, which will be a Minnesota corporation. At the same time, the new subsidiary will assume all of NSP's liabilities associated with the assets that it receives in the contribution. NSP's preferred stock and trust-originated preferred securities will remain in the holding company Xcel Energy.

Common stock of New NSP Utility Sub, at a par value and share level which have not yet been determined, will be wholly owned by Xcel Energy. The resulting New NSP Utility Sub capitalization will therefore include short-term debt, first mortgage bonds and other long-term debt associated with utility operations, and common equity issued to Xcel Energy (net of adjustments described in Note 2).

2.

The assets, liabilities, equity and results of operations of all subsidiaries of NSP have been eliminated from consolidated NSP amounts to reflect the transfer of ownership and control of such subsidiaries to Xcel Energy as a result of the merger. Xcel Energy's equity investment in New NSP Utility Sub, and the corresponding common equity of New NSP Utility Sub, are assumed to reflect the reduction in New NSP Utility Sub net assets related to the transfer of ownership of investments in NSP subsidiaries to Xcel Energy as a result of the merger.

3.

NSP financing of subsidiary capital and cash flow requirements has been adjusted to reflect the transfer of such items to Xcel Energy except for immaterial financing of refuse-derived fuel operations previously transferred to NRG Energy, Inc. Pro forma adjustments reflect the elimination of (a) notes receivable and advances from subsidiaries; (b) NSP debt incurred to finance the notes and advances; (c) interest income earned on the notes and advances; and (d) interest expense accrued on the debt incurred to finance the notes and advances.

4.

After the merger, NSP-Minnesota will not retain ownership of most of its subsidiaries currently being consolidated. Consequently, intercompany transactions between NSP and its current subsidiaries have not been eliminated in the pro forma financial statements (except as discussed in Note 3).

The most significant intercompany transactions are power sales to and purchases from the Wisconsin Company pursuant to an interchange agreement with NSP. Although the interchange pricing and cost sharing arrangements may be restructured as a result of the merger, at this time the amount of any changes to interchange power purchases or sales is expected to be immaterial. Consequently, no pro forma adjustments have been made to operating revenues, operating expenses, or accounts receivable from (or payable to) associated companies for the effects of interchange restructuring.

5.

The allocation between NSP and NCE and their customers of the estimated cost savings resulting from the merger, net of the costs incurred to achieve such savings, will be subject to regulatory review and approval. These summarized pro forma amounts do not include any of the estimated cost savings

expected to result from the merger of NCE and NSP. However, the reported amounts for NSP include approximately $25 million of deferred nonrecurring merger costs as of Dec. 31, 1999, mainly those directly attributable to the merger transaction. Assuming the business combination is accounted for as a pooling of interests, these costs will be expensed upon the consummation of the NCE/NSP merger. The pro forma income statement information amounts do not reflect any of these costs. The pro forma balance sheet information has been adjusted to reflect a write-off of the deferred costs and a related reduction of retained earnings.

Exhibit 99.04

New NSP Utility Sub

Unaudited Pro Forma Condensed Income Statement

Year Ended December 31, 1999

(In thousands)

New NSP Utility Sub

Unaudited Pro Forma Condensed Income Statement

Year Ended December 31, 1998

(In thousands)

New NSP Utility Sub

Unaudited Pro Forma Condensed Income Statement

Year Ended December 31, 1997

(In thousands)

New NSP Utility Sub

Unaudited Pro Forma Condensed Balance Sheet

December 31, 1999

(In thousands)

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