Yesterday, Japan’s prime minister, Naoto Kan, announced that the government was scrapping a planned expansion of nuclear power, which currently provides about a third of Japanese electricity. Instead, the government would redouble efforts to expand its renewable energy portfolio, Kan said. The turnaround followed Kan’s urging  last week that a reactor in Hamaoka, near an active seismic zone, be shut down; the company that runs the plant has agreed and is building a seawall to protect the plant from tsunamis when it reopens in 2 years. The Fukushima disaster “gives the Japanese an opportunity,” Japan business expert William Tsutsui of Southern Methodist University in Dallas, Texas, tells ScienceInsider. “It could be a shot in the arm for renewable technologies.”
In a useful article  Time’s Krista Mahr reviews various sectors of the Japanese energy economy to assess its options to get greener:
because of the nation's special attention to developing nuclear power since the oil crisis of the 1970s, the renewable sector is surprisingly anemic for a nation where expertise in renewable technologies is so high and where every gas station has approximately 24 different kinds of recycling bins. Less than 1% of Japan's electricity comes from wind, solar, geothermal and biomass.
Of those renewable options, wind energy probably has the greatest potential for the medium term in Japan, but it faces the challenge of an electrical grid infrastructure that’s poorly suited to take the power it generates, Mahr noted. Geothermal power is another area Japan could turn to:
Japan has the third largest geothermal energy potential in the world after the U.S. and Indonesia. But in terms of harnessing that heat and turning it into power, Japan only ranks 8th, after countries with drastically smaller populations, like Iceland and New Zealand. Today, Japan only generates about .1% of its electricity in 19 geothermal energy plants, many of which are located in the Tohoku region where the Fukushima nuclear power plant is located.
Some think Japan will be unable to forgo expansion of nuclear power in the long run. “The government is still going to want a nuclear strategy, but it will be 2 to 3 years before anything is rolled out in public,” Tsutsui told Insider.
The Japan Times quotes Osaka University nuclear expert Keiji Miyazaki, who agrees the government will eventually return to nuclear power:
Miyazaki, who has studied the capacity of other energy sources including geothermal, solar and wind power generators, concluded that each option lacks the capability of nuclear power in efficiency, cost performance and environmental protection.
It is regrettable that Fukushima No. 1 suffered a serious accident, he said, but "it is the nature of any machine to malfunction eventually."
"It is impossible to make nuclear power stations absolutely safe, but maximizing the safety is possible if precautionary measures are properly taken," Miyazaki said.
He pointed out that while Fukushima No. 1 was crippled by the tsunami, other nuclear plants survived the disaster without much damage.
"This is not about whether nuclear power is necessary or not despite its dangers. It is about properly managing a reactor and making it safe," he stressed.
The debate over nuclear power continues in other countries. Environmental blogger Damian Carrington of the Guardian, noting that Japan’s move follows Germany’s announcement  that it was also ditching plans to expand nuclear power, asks whether the United Kingdom should follow suit.
But Carrington acknowledges that a U.K. climate change panel has just called  for nuclear power to provide 40% of British power.