HONG KONG — Coal-fired power plants have propelled much of China’s economic rise for decades, helping make the nation the world’s biggest emitter of greenhouse gases. Even with economic growth slackening, and other energy sources taking hold, new coal plants have been added.

Now Beijing is trying to slow things down.

In guidelines released on Monday, China halted plans for new coal-fired power stations in many parts of the country, and construction of some approved plants will be postponed until at least 2018.

The announcement, by the National Development and Reform Commission and the National Energy Administration, means that about 200 planned coal-fired power generators — those seeking approval and those approved but not yet under construction — may not be completed, said Lauri Myllyvirta, who analyzes China’s energy production for Greenpeace.