Selling electricity was once a relatively simple proposition.

A utility fired up a power station with coal, natural gas, oil or some other fuel, and sent electricity down a wire to customers.

But the business model for the electric power industry has changed dramatically in the U.S. over the past 25 years, with deregulation opening markets to competing sellers of electricity, and new technologies offering a dizzying array of options for consumers.

The latest sign of change in the industry is the announcement by Edison International of a new subsidiary called Edison Energy that sells “energy as a service” to commercial and industrial customers throughout the U.S. (Read more)