The U.S. Environmental Protection Agency will unveil a proposal Monday to cut emissions at coal-fired power plants — the biggest step yet by the Obama administration to combat global warming, and a move with major implications for Wisconsin, because coal generates more than half the state's electricity.
EPA Administrator Gina McCarthy has said the agency will give broad latitude to states to meet targets for carbon emissions. While those targets are not yet known, a mandate to cut emissions by 25% by 2030 is expected, says Mark Thimke, a Milwaukee energy and environmental lawyer who follows the issue closely.
To meet that, states will need to employ a suite of alternatives:
■Cap-and-trade systems, which let low producers of carbon sell credits to higher producers, resulting in an overall reduction in emissions.
■More renewable energy.
■Greater use of technologies to cut energy use in businesses and homes.
■Greater reliance on natural gas, which produces about 50% fewer emissions than coal.
A World Resources Institute study that analyzed Wisconsin's energy picture concluded that expanding several technologies — natural gas, energy efficiency, wind and solar — could slash emissions of greenhouse gases by more than 40%.
In 2011, Wisconsin released 96 million tons of greenhouse gases. Of this, 41% came from coal plants, according to state figures.
For Obama, who has already moved to curb emissions from cars and trucks, "this is the crowning achievement," said Michael Kraft, professor emeritus of environmental policy at the University of Wisconsin-Green Bay.
"About 40% of U.S. greenhouse gas emissions come from coal-fired power plants, and if you can move away from that, that's a big, big deal," he said.
The regulations come less than a month after the EPA issued a national climate assessment, prepared by a panel of scientists, that underscored the urgency of addressing rising carbon levels.
"Climate change, once considered an issue for a distant future, has moved firmly into the present," the report said. "Summers are longer and hotter, and extended periods of unusual heat last longer than any living American has ever experienced."
