US President Barack Obama is due to unveil what he called "the biggest, most important step we have ever taken" in tackling climate change.
The aim of the revised Clean Power Plan is to cut greenhouse gas emissions from US power stations by nearly a third within 15 years.
The measures will place significant emphasis on wind and solar power and other renewable energy sources.
However, opponents in the energy industry have vowed to fight the plan.
They say Mr Obama has declared "a war on coal", the source of more than a third of power requirements in the US.
The revised plan will aim to cut carbon emissions from the power sector by 32% by 2030, compared to 2005 levels.