U.S. District Judge Valerie Caproni in Manhattan rejected claims that federal law preempted New York and its Public Service Commission from offering credits to promote clean energy and reduce reliance on fossil-fueled or gas plants.

The plaintiffs said the credits could boost electric bills for New York's "captive ratepayers" by $7.6 billion over 12 years, and violate the "dormant" Commerce Clause by impeding Congress' power to regulate commerce among states.

But the judge said New York's "zero-emissions credits" program was "plainly related to a matter of legitimate state concern": the production of clean energy, and reduction of emissions from other energy that could add to global warming.

"The New York program is constitutional," Caproni wrote. "Fatal to plaintiffs' argument is their failure to offer any cogent explanation why ZECs are preempted but other state incentives to generate clean energy - such as tax exemptions, land grants, or direct financial subsidies - are not."