Japan has seen a rapid increase in solar power facilities since the incentives were launched five months ago to promote investment in clean energy, but Hokkaido is facing a glut, trade minister Yukio Edano said Friday.

The number of solar power facilities nationwide rated at over 1,000 kw and approved by the Ministry of Economy, Trade and Industry were providing about 1.8 million kw of capacity in October. About 341,000 kw of that is scheduled to be installed in Hokkaido, the ministry said.

The imbalance apparently emerged as Hokkaido is blessed with plenty of land priced relatively cheap, it said.

But the capacity of its power lines and related facilities is relatively low, which means capacity might be limited to between 400,000 and 600,000 kw.

At the same time, Hokkaido is a promising area for wind power, and the ministry has pointed to the need to leave room available for such facilities.

"Mega solar power systems can be installed anywhere in the country, and there is sufficient room to establish them in regions other than Hokkaido," Edano said.

Under the feed-in tariff scheme that kicked off in July, utilities are required to buy all electricity generated by renewable sources, such as solar, wind, water and geothermal energy, at preset premiums for up to 20 years, and are allowed to pass the costs onto consumers.