Germany's solar power output was about twice that of Japan in 2006, according to a recent study conducted by a research organization.
Japan had long been a forerunner in solar power. But in 2005, Germany unseated Japan as the world's largest solar power generating country and the gap in output between the two is widening, according to the Institute for Sustainable Energy Policies.
The results of the study by ISEP also suggests Japanese companies, which still control about 50 percent of the world's production of solar power generators, are facing increasingly tough competition from German and Chinese manufacturers.
"Japan's solar power generation will further fall behind other countries if we don't drastically review current energy policies," said Tetsunari Iida, executive director of the nonprofit research body.
Germany's output stood at 3.06 million kilowatts at the end of 2006, increasing by 1.15 million kw from the previous year, ISEP said.
In contrast, Japanese output last year grew by only 250,000 kw, or less than one-fourth of the growth in Germany, to total 1.67 million kw, the research body said.
Sharp Corp. is the world's top maker of solar power generators, with a 30 percent market share. But it did not see much of an increase in production volume from 2005 to 2006, while German and Chinese rivals showed a rapid expansion during the same period, ISEP said.
ISEP's Iida said the Japanese law requiring power firms to generate a certain amount of electricity by using new energy is not functioning.
In fiscal 1994, the government introduced subsidies for individuals purchasing solar power units. This helped the country become and stay the leading solar power country. But in fiscal 2005, the subsidies ended.
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