On Friday, in a move that has already caused dismay in industry and among Congressional Republicans, the Obama administration proposed the first-ever federal limits on power plant emissions of carbon dioxide, which account for nearly 40 percent of the greenhouse gases America contributes to a gradually warming climate.

The move, the first in a suite of executive actions on climate change promised by President Obama in June, is a welcome sign of his determination to move ahead on his own authority and bypass a Congress whose interest in tackling global warming is virtually nil.

The proposed limits — which apply only to new power plants — will have no immediate effect on carbon emissions. But the long-term consequences for the way the nation produces energy will be significant.

The rules would restrict emissions at new natural gas-fired plants to 1,000 pounds of carbon dioxide per megawatt-hour, and at new coal plants to 1,100 pounds per megawatt-hour. Because existing coal plants, even advanced ones, produce about 1,800 pounds per megawatt-hour, industry will find it virtually impossible to build new coal plants without capturing and storing some or all of their carbon emissions — a technology the administration has promised to promote but which has not been commercially demonstrated on a wide scale. New gas-fired plants should easily fit under the new limits because they now produce only about 800 to 850 pounds per megawatt-hour.