The suspension is likely to have a significant impact on the development of China's power industry. But officials with the State Environmental Protection Administration declined to comment on the possibility that during periods of acute shortages, boosting capacity would be given priority over the protection of the environment, according to an Interfax report.

The power projects – many of them new coal-fired plants or expansions of existing ones – were being built in 12 different provinces as part of a push to address severe electricity shortages.

Announcing the suspensions, State Environmental Protection Administration vice director Pan Yue said environmental protection facilities must be designed, built, and put into operation simultaneously with the main body of all projects.

The central government wanted to curb any slack from localities who went ahead with construction without following proper environmental procedures Pan said, according to news agency Xinhuanet.

"We must sharpen our teeth," he said. "We must never be rubber stamps. We must take concrete actions."

Pan also said the quality of environmental assessments must be improved.

"We shall introduce institutions to China to improve the overall assessment quality," he said.

But the Datang International Power Generation Company, whose Zhejiang Wushashan Power Plant Project was among the suspended projects, told Interfax it had met environmental requirements.

"We have incorporated all necessary environmental protection measures in our project proposal, including the installation of de-sulfurization and de-nitrification equipment," a Datang International official said.

Asked why the project has been suspended, Pan told Interfax that it was up to the State Environmental Protection Administration to decide which projects to suspend and it had chosen to make an example of the 30 halted projects.

He said some projects might be allowed to resume but others would be cancelled.