The rumors have turned to reports. President Obama will release climate change policy initiatives in the coming weeks, or maybe even next week, according to remarks made by White House senior officials on Wednesday.  

The regulations will focus on on carbon dioxide emissions from existing power plants, according to The New York Times. Power plants are an obvious target because they are responsible for nearly 40 percent of greenhouse gas emissions.

Proposed regulations for new plants have already made the prospect of new coal-fired power plants pretty grim in the U.S. In anticipation of stricter rules, many regions are looking at ramping up existing gas-fired power plants or building new ones, along with increased renewables and more demand response.

But now the administration is turning its efforts to existing power plants. About 40 percent of total electricity generation in the U.S. currently comes from coal, still the single largest source. Natural gas accounts for a growing proportion of generation, and now provides between 20 percent and 30 percent of generation, according to the U.S. Energy Information Administration.  

"We have never as a country put forward a regulation on new or existing coal plants before," Heather Zichal, the White House coordinator for energy and climate change, said at an event on Wednesday. "And I think whether that's the president or the team at EPA, everyone is very focused on making sure that those policies are done the right way, that those policies are going to provide the right incentives going forward, the right policy to really drive emissions reductions. I'm very confident that we'll land that policy in the right place."

The policy will not just be about coal-fired power plants, according to The New York Times, but will also have new initiatives pertaining to renewable energy (more on public lands) and energy efficiency (more everywhere).

Environmentalists praised the more decisive action, while Republicans and some Democrats are likely to fight it. But Obama’s proposal will not rely on congressional approval, Zichal said. In 2007, the Supreme Court gave the U.S. Environmental Protection Agency authority to regulate greenhouse gases. Even without congressional backlash, the coal industry will almost certainly launch a legal battle.

“The president needs to put the full force of his office behind new regulations that will truly curb greenhouse gas emissions,” Ned Helme, president of the Center for Clear Air Policy, said after Obama mentioned climate change in his speech in Berlin on Wednesday. “For too long now, he has produced little action. I’m encouraged that he will finally act and not just ask.”

Of course, shutting down new coal in the U.S., as well as some existing coal, doesn’t stop the mining. Increasingly, U.S. coal is just being sent overseas, primarily to China, which will take all the energy resources it can get.

Any proposed rules can take years to get into place, because states have to file plans outlining how they would comply, and that doesn’t include any legal action that can hold up stricter regulations for even longer.

Stay tuned for more details as they emerge.