TOKYO -- Japan's government earlier this month laid out its vision of the nation's future energy supply. Now comes the hard part.
The new plan, unveiled June 1, says renewable sources should cover 22-24% of domestic power needs by 2030. Nuclear reactors, meanwhile, would take care of 20-22%.
Yet the nation is still struggling to solve the dilemmas left by the March 2011 earthquake and tsunami, which triggered meltdowns at the Fukushima Daiichi nuclear power station. In the aftermath, all power reactors were gradually taken offline. Four years on, not a single reactor has been fired up, though some are expected to be restarted sooner or later.
The prospects for reaching the renewable target are also unclear. At present, such power sources account for around 10% of Japan's supply.
In the windy northern town of Oma, Aomori Prefecture, a would-be nuclear power plant sits reactorless. Prior to the 2011 catastrophe, about 1,700 engineers toiled on the project led by Electric Power Development, or J-Power. Now, most of them are gone.
Back in 1976, Oma's local commerce and industry association sought to bring a nuclear plant to the town, which overlooks the Tsugaru Strait between Hokkaido and Japan's main island of Honshu. The plan was seen as an economic kick-starter. After drawn-out negotiations over compensation for local fishermen and environmental surveys, construction finally started in 2008. The Fukushima disaster brought it all to a halt.
"I hope the Oma plant will be put online as soon as possible, but I wonder when it will happen," said Mitsuharu Kanazawa, Oma's mayor.
He is not alone in wanting to see Japan return to nuclear generation. Since reactors emit no carbon dioxide, the central government seems to see them as "magic wands" for lowering electricity costs and reducing greenhouse gas output.
But safety fears run deep among the public. And reactors must undergo rigorous examinations by the Nuclear Regulation Authority before they can be switched on.
If Japan is to have any hope of achieving the 20-22% nuclear power ratio, it will need to restart the bulk of its idle reactors. Prior to the Fukushima disaster, the country had 54 such units running. Eleven, including six at the stricken Fukushima plant of Tokyo-area utility Tepco, are to be decommissioned.
In addition, there are safety concerns about roughly 10 other reactors, due to the existence of active seismic faults nearby, utilities' failure to meet the latest screening standards and other reasons.
In mid-May, the nuclear watchdog's panel of experts inspected Hokuriku Electric Power's Shika nuclear power station in Ishikawa Prefecture, on the Sea of Japan coast. They said faults running beneath the reactors may be active, casting doubt on the plant's future.
The regulator stresses that its job is to ensure power plants are safe -- not to clear a path to the government's goals. "The energy mix has nothing to do with us," said Shunichi Tanaka, the watchdog's chairman.
These question marks mean Japan may have to consider another, perhaps even more controversial option alongside restarts -- building brand new nuclear facilities.
"Unless Japan openly discusses the need to build new nuclear power plants, it will be all but impossible to raise the ratio up to [even] 15%," said Takeo Kikkawa, a professor at the Tokyo University of Science who specializes in energy policy and was involved in charting the government's energy policy.
In the meantime, electric utilities have had no choice but to turn to aging thermal plants. But these generators burn fossil fuels, resulting in extra costs and bigger environmental footprints.
In Wakayama Prefecture, Kansai Electric Power's Kainan power station is more than 40 years old. Rust is easy to spot. The control room is filled with old-fashioned equipment. "Operations here have yet to be automated," said Fumihiro Kamatani, who manages the facility. "We rely on our experienced engineers to do everything manually -- all 200 or so procedures."
The No. 2 generator was taken offline in 2001. But following the nuclear shutdowns, Kansai Electric decided to bring it back due to the risk of summertime power shortages. This is just a stopgap, however -- not a long-term solution.
All of this makes it essential for Japan to progress on the renewables front. But is it realistic to expect a 12-14 percentage point increase in the ratio by 2030?
Geothermal power could at least bring the country closer to that goal.
While touring reconstruction projects in Fukushima, Prime Minister Shinzo Abe on May 31 visited a geothermal power station in the town of Yanaizu. "We need to capitalize on geothermal's huge potential," he said.
The government is seeking to harness not only underground heat but also wind and biomass.
In the Hokkaido city of Mombetsu, Sumitomo Forestry plans to launch by the end of 2016 a biomass power plant that uses discarded wood chips as fuel. The facility will have an output capacity of 50,000kW, making it one of the nation's largest biomass facilities.
Major trading house Mitsui & Co. and other companies intend to push ahead with similar projects in Hokkaido.