Japan's abundant renewable energy sources have not been sufficiently tapped due to a lack of government initiatives, Hans-Josef Fell, a member of the German parliament and the Green Party's spokesman for research and technology issues, said Wednesday.

Speaking at a one-day symposium on renewable energy in Tokyo, Fell said the government should encourage the use of energy sources such as wind, solar and geothermal energy.

He said that in April 2000, Germany enacted the Renewable Energy Law, which obliges electricity companies to buy all power generated through renewable energy sources at fixed prices.

No such system exists in Japan, and renewable energy prices are decided by the market, he said, adding the prices are more costly than for fossil fuels or nuclear energy.

A law that took effect last April obliges utilities in Japan to increase the percentage of power drawn from renewable energy sources, including waste incineration, to 1.35 percent of total electricity supply by 2010. But Fell said this scheme is not enough.

"The existing benefits (gained by selling power from renewable energy sources) are insufficient (for the power suppliers) to counter the investment risks," he said.

After fossil fuels have been exhausted, Japan will be unable to meet its electricity demands without tapping into renewable energy sources, he said.

He said that in Germany, renewable energy accounted for 6 percent of total electricity supply in 2000.

But with the enactment of the Renewable Energy Law, the German government aims to double that figure by 2010, he said.

The symposium was aimed at preparing for an international conference on renewable energy to be held in Germany in June.

Panelists included House of Representatives member Taro Kono, and officials of Toyota Motor Corp. and the Natural Resources and Energy Agency.