EXHIBIT 21 WISCONSIN POWER AND LIGHT COMPANY AND SUBSIDIARIES SUBSIDIARIES The subsidiaries and affiliates of the Company as of December 31, 1993, are as follows: Percentage of Voting Stock State of Owned by the Name of Subsidiary Incorporation Company South Beloit Water, Gas and Electric Company.. Illinois 100% NUFUS Resources, Inc.......................... Wisconsin 100% REAC, Inc..................................... Wisconsin 100% Wisconsin River Power Company................. Wisconsin 33-1/3% Wisconsin Valley Improvement Company.......... Wisconsin 13% No separate financial statements are submitted for any subsidiary since none of these subsidiaries qualifies as a significant subsidiary under SEC rules.