Policy Institute in April 2011 estimated that Japan could produce 80,000 MWs and meet more than half its electricity needs with conventional geothermal energy.
It added that steam and hot water billow and gush from deep below the ground at Japan's tens of thousands of famed hot springs and could be harnessed to drive turbines that generate electricity in a clean, safe and stable way.
Although Japanese high tech companies are leaders in geothermal energy technology and export it, its use is miniscule in the island nation, which has for decades relied on imported fossil fuels and nuclear power.
Japan's parliament was expected to pass a law to promote renewable energy such as wind, solar and geothermal by forcing power utilities to buy it at fixed prices and letting them pass extra costs onto consumers.
Dr Yoshiyasu Takefuji professor of Tokyo's Keio University and a prominent researcher of thermal electric power generation said that "Japan should no doubt make use of its volcano, magma and other geothermal energy. The March 11th 2011 disaster caused a lot of sadness, but it has also changed people's thinking about energy."
Japan is located on the Pacific Ring of Fire at the juncture of four tectonic plates that slowly grind along, driven by the flow of super hot magma below, creating stresses that are released in earthquakes. The most powerful of these in Japan's recorded history, a magnitude 9.0 seabed quake, struck on March 11th 2011, triggering the huge tsunami that killed more than 20,00 people and set off the Fukushima nuclear disaster.
The crisis has sparked a backlash against atomic power, which previously made up 30% of Japan's energy needs, and increased interest in alternative energies, which account for only eight percent, most of it hydro.
In northern Japan, 60 kilometers from the tsunami ravaged coast, lies Japan's first geothermal power plant, built in 1966 at the hot spring resort of Matsukawa in Hachimantai. The 23,500 kilowatt plant, set amid mountains where the smell of sulphur hangs thick in the air, never stopped running after the quake, while in contrast, two thirds of Japan's reactors remain offline for safety checks.
Mr Kazuhiro Takasu head of the plant said that Japan must accept that switching to renewable will carry initial extra costs, but that a new JPY 10 billion geothermal plant would break even in a few decades. He added that "People are now talking about renewable energy, but such excitement can easily ebb off after a while."
For now, geothermal makes up less than 1% of the energy mix in Japan, a resource poor economic powerhouse that imports its oil, coal and gas and has invested heavily in nuclear energy since the 1970s oil crisis. The biggest hurdle to geothermal, most experts agree, is the high initial cost of the exploration and drilling of deep earth layers that contain hot water, and of then constructing the plants.
Another problem is that Japan's potentially best sites are already being tapped for tourism with popular onsen hot spring resorts or are located within national parks where construction is prohibited.
Mr Hideaki Matsui, senior researcher at the Japan Research Institute, said that "geothermal energy is a decades long project. We also have to think about what to do for now as energy supplies will decline in the short term".
Nonetheless, argue its proponents, geothermal energy has vast potential Japan is estimated to have some of the world's largest reserves of usable underground heat, behind the United States, the Philippines and Indonesia, but is ranked only sixth in terms of geothermal generation capacity.
Ironically, Japanese giants such as Toshiba and Mitsubishi are already global leaders in geothermal power technology, with a 70% market share. In 2010, Fuji Electric built the world's largest geothermal plant in New Zealand.
