The state allowed direct retail access. Generators can and do enter into direct deals with commercial and industrial users. The state also benefited from good circumstance. The PJM Interconnection had been running an integrated power grid for Pennsylvania, New Jersey, Maryland, Delaware, D.C., and part of Virginia since 1927. That greatly eased the transition.
Power supply is plentiful.
The PJM can call on 57,000 megawatts for its 9.5 million customers. The Cal-ISO, in comparison, has roughly 45,000 megawatts for 10 million customers. And since 95 percent of the state's electricity comes from nuclear or coal fired plants, the natural gas price spike didn't send the wholesale price cost through the roof. Electricity choice has, not surprisingly, been most enthusiastically embraced in areas with high rates, like Philadelphia. Pennsylvania, while a success so far, ought not to be mistaken for a totally free market.