Its own unregulated subsidiary, Northeast Generation, paid $865.5 million for 1,329 megawatts of hydroelectric plants.
Under the plan, Northeast would acquire the assets of the HEC Energy Corporation and place them in a newly formed unregulated subsidiary.
Western Resources will be made up of the combined companies' unregulated subsidiaries.
In addition to electricity, the cooperative also provides telephone and Internet service through unregulated subsidiaries.
In 1981, Southern Company became the first electric utility holding company in 46 years to diversify its operations by forming an unregulated subsidiary.
And sometimes regulators allowed utility holding companies to transfer plants from their regulated utilities to unregulated wholly owned subsidiaries.
This means that customers are protected from the losses the local utility may incur from investments made by its unregulated subsidiaries or affiliates.
For more than a decade, insurers in Texas have been allowed to form unregulated subsidiaries, initially intended as a way of providing homeowner coverage to riskier policyholders.
It sells electricity through Select Energy, its unregulated subsidiary.
The new plant's construction cost, $16 million, was put up by Fuelco, an unregulated subsidiary of the Public Service Company of Colorado.