Exhibit 99.03

Xcel Energy Summarized Pro Forma Information

    The following summary of unaudited pro forma financial information for Xcel Energy gives effect to the merger using the pooling of interests method of accounting. Under this accounting method, NSP's and NCE's balance sheets and income statements are treated as if they have always been combined for financial reporting purposes. This unaudited pro forma summarized financial information should be read in conjunction with the historical financial statements and related notes of NSP and NCE, which are included in the 1999 Annual Reports on Form 10-K of the respective companies.

    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 the combined company'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 the combined company.

Xcel Energy—Notes to Unaudited Pro Forma Combined Condensed Financial Statements

1.

The unaudited pro forma combined condensed financial statements reflect the conversion of each NCE share into 1.55 shares of common stock of the combined company and the continuation of each NSP common share outstanding as one share of common stock of the combined company ($2.50 par value), as provided in the merger agreement. The unaudited pro forma combined condensed financial statements are presented as if the companies were combined during all periods included therein.

2.

The unaudited pro forma combined condensed income statements reflect certain reclassifications to conform to the presentation of operating results. These reporting adjustments include: (a) separate presentation of nonregulated revenues and equity earnings in Operating Revenues; (b) separate presentation of all nonregulated expenses, including project write-downs, in Operating Expenses; (c) presentation of nonregulated interest and other income, including gains from project sales, in Other Income (Deductions)—Net; and (d) presentation of all income taxes (regulated and nonregulated) on a single line before arriving at Net Income.

3.

The unaudited pro forma combined condensed balance sheet reflects reporting adjustments to conform to the presentation of: (a) investments and deferred charges (in Other Assets); and (b) nonregulated property (in Property, Plant and Equipment) and (c) construction work in progress (in Other Property, Plant and Equipment).

4.

The allocation of the estimated cost savings resulting from the merger to NSP, NCE and their customers, net of the costs incurred to achieve such savings, will be subject to regulatory review and approval. At the time the merger agreement was signed, cost savings resulting from the merger were estimated to be approximately $1.1 billion over a 10-year period, net of transaction costs (including fees for financial advisors, attorneys, accountants, filings and printing) and net of costs to achieve the savings. 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 and NCE include approximately $25 million and $20 million, respectively, 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.

5.

Intercompany transactions (including purchased and exchanged power transactions) between NSP and NCE during the periods presented were not material and, accordingly, no pro forma adjustments were made to eliminate such transactions.

Xcel Energy

Unaudited Pro Forma Combined Condensed Statements of Income

Year Ended December 31, 1999

(In thousands, except per share amounts)

See accompanying Notes to Unaudited Pro Forma Combined Condensed Financial Statements

Xcel Energy

Unaudited Pro Forma Combined Condensed Statements of Income

Year Ended December 31, 1998

(In thousands, except per share amounts)

See accompanying Notes to Unaudited Pro Forma Combined Condensed Financial Statements

Xcel Energy

Unaudited Pro Forma Combined Condensed Statements of Income

Year Ended December 31, 1997

(In thousands, except per share amounts)

See accompanying Notes to Unaudited Pro Forma Combined Condensed Financial Statements

Xcel Energy

Unaudited Pro Forma Combined Condensed Balance Sheets

December 31, 1999 (In thousands)

See accompanying Notes to Unaudited Pro Forma Combined Condensed Financial Statements

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Exhibit 99.03