TOKYO — Japan plans to soon require electricity companies to buy surplus power generated by household solar panels at about twice the current price, a government official said Tuesday.

The scheme, to start as early as the fiscal year beginning in April, aims to promote solar power as part of efforts to cut greenhouse gas emissions that drive global warming, an industry ministry official said.

“Japan has already led solar power technology in the world,” the official told AFP. “With the scheme, we would like to firmly secure the lead.”

Japan’s utilities now voluntarily buy surplus electricity from domestic solar panels at around 24 yen (25 cents) per kilowatt hour, he said.

The ministry plans to submit a bill to parliament that would make it mandatory for power companies to purchase the unused solar power from households at around 50 yen per kilowatt hour, the official said.

The premium rate, which could be set for 10 years, would help homes and companies recover the initial cost of installing photovoltaic cell systems.

Electricity companies would be expected to raise charges for conventional power to meet the additional expense.

Trade Minister Toshihiro Nikai Tuesday informed the Federation of Electric Power Companies of Japan about the scheme, and federation officials agreed to “cooperate” in introducing it, the official said.

Japan has pledged a 10-fold increase in solar power use by 2020 from current levels and aims to halve prices of solar power systems in about four years.

Resource-poor Japan has looked for ways to reduce its dependency on foreign oil, while vowing to reduce carbon emissions by up to 80 percent by 2050.

Japan, which hosted talks that led to the Kyoto Protocol, is badly behind in meeting its own targets under the UN treaty, as the government has hesitated to restrict industrial carbon output amid the current economic crisis.