California's two senators this week offered markedly different approaches to slowing global warming, with Dianne Feinstein saying she may move to exempt power companies from her home state's landmark global warming laws and bring them under federal regulation instead.
Coal-fired and other fossil-burning power plants are the largest source of greenhouse gases in the United States, producing a third of all emissions.
A draft of Feinstein's bill included an exemption clause, but it was omitted before she introduced it Wednesday after protests from representatives of Gov. Arnold Schwarzenegger, legislative leaders and some environmental groups.
In an interview Wednesday, however, Feinstein did not rule out adding it back at some point.
"I want to take another look," she said.
Under the clause, power plants would be exempt from any state laws regulating greenhouse gases, including several in New England as well as California. Feinstein said she had removed it for now because "I know the environmentalists have concern."
The bill she introduced, which deals just with the electricity sector, calls for a market-based cap and trade system. The bill would ratchet down electricity sector emissions 25% below projected levels by 2020.
Sen. Barbara Boxer, in contrast, has signed onto a bill introduced Tuesday that covers a wider spectrum of greenhouse gas sources, including motor vehicles, and would reduce U.S. emissions to 1990 levels by 2020 and to 80% below 1990 levels by 2050. The 2050 goal goes beyond what Feinstein's legislation calls for. The Boxer bill has no mandatory cap and trade program.
Many environmentalists favor the approach Boxer is sponsoring because it is broader.
"Boxer's bill is the gold standard," Jason Barbose of Environment California said.
Feinstein intends to introduce several other bills in coming months that would also address global warming, her spokesman said.
Both senators are part of the Democratic majority, but Boxer chairs the Senate Environment and Public Works Committee and could play a key role in moving global warming legislation. Boxer called Feinstein's bill -- one of many that have been introduced -- a "positive addition" to the debate and said Feinstein would be invited to discuss her bill with the committee.
