Sri Lanka's energy minister blamed China on Thursday for power shortages and high electricity prices, saying the island's biggest power station built by a Chinese company has suffered frequent breakdowns.

Energy Minister Pavithra Wanniarachchi said problems with the 300-megawatt coal-powered plant, the largest single electricity generator in the country, was forcing Sri Lanka's main state-run energy company to buy more expensive electricity from private firms.

"The coal power plant is breaking down frequently. We are asking the Chinese to fix it," Wanniarachchi told reporters in Colombo. "These failures are not good for the image of China."

"We expected to use this plant for about 25 years without any major problem, but within three years it has stopped working," she said, adding the plant had suffered more than 35 breakdowns since being commissioned in mid-2011.

Wanniarachchi said top officials from the contractor, China Machinery Engineering Corp (CMEC), were due to meet with her on Friday to discuss the problem.

Energy ministry secretary M.C. Ferdinando said buying power from private diesel power stations was prohibitively more expensive than sourcing from the coal plant located along the island's north-western coast.

"Tariffs could be brought down if we did not have to resort to other (diesel) sources of power to augment the shortages caused by the coal plant (breakdowns)," Ferdinando said.

Sri Lanka's electricity tariffs are among the highest in the world with a kilowatt hour, or a household unit, costing up to 35 US cents.

There was no immediate comment from CMEC, but its website displayed an official Xinhua news agency report from September 2012 saying the company was confident of the "stability" of the power plant in the long run.