Before last year's tsunami, nuclear power generated close to 30% of Japan's electricity needs, with an installed output capacity of 46 gigawatts. But as of July 1 of this year, all but two of Japan's 50 nuclear plants remained shut down. Whether the others eventually restart will depend on the outcome of safety tests and politics—a June 2012 survey by the Pew Research Center found that 70% of Japanese believe the country should reduce its reliance on nuclear power. Here's a look at the alternative energy sources Japan is tapping to fill the atomic-power void and build a more secure energy future, with or without nuclear.LIQUID NATURAL GAS Japan is the world's largest buyer of gas, which comes mainly from Australia, Qatar, and Southeast Asia. From 2010 to 2011, its use rose by 20%; now it supplies more than 30% of Japan's electricity. Three planned plants will add 3.4 GW of capacity when they open in 2016, but reliance on gas puts Japan in a bind: It pays a premium on imports compared to other nations, and many contracts are set to expire in the next decade, forcing it to renegotiate or find new suppliers. SOLAR In 2009, just 3% of Japan's electricity came from renewable sources other than hydroelectric. But with new government incentives, Japan could soon become the second-biggest market for solar power (after Germany). The enticing long-term contracts to providers should expedite installation of sun-soaking capacity, but Japan has a long way to go—among the G7 group of industrialized countries, only Canada got less of its energy from renewables in 2011. CRUDE OIL At roughly 4.5 million barrels a day, Japan's petroleum consumption ranked third in the world in 2011. Eighty-seven percent of that oil came from the Middle East via the Strait of Hormuz, a politically vulnerable area under the control of Iran, which has threatened to cut off shipping. Additional capacity may come from the opening of mothballed plants, though the Japanese government's pledge to lower greenhouse gas emissions favors the use of cleaner-burning natural gas. GEOTHERMAL With its location on the Pacific Ring of Fire, Japan has significant geothermal resources, most of which remain untapped. The recent decision to allow new projects in the country's national parks could help grow capacity to about 2 GW by 2020. But up-front development costs are high: It can cost $7 million to assess a site for a 20 MW plant, and another $20 to $40 million to drill. Plus, it can take up to seven years to go from discovery of a location to commercial operation. COAL In 2010, plants fueled by coal—shipped mainly from Australia—supplied about 25% of Japan's power. With three facilities presently under construction, and the potential to increase the output of existing plants, coal-power generation could jump. But several plants were damaged in the 2011 earthquake and have yet to resume operations; plus, more use of coal would contradict Japan's 2010 Basic Energy Plan, which called for reducing coal power from 25% to 10% of total consumption. WIND A 126 MW wind farm, Japan's biggest, is planned to launch in 2016, but with limited land area for farms and a steep offshore seabed, adding significant capacity will likely require floating turbines connected via underwater cable. The Japan Wind Power Association has set a goal of producing 50 GW by 2050, with half coming from offshore sites. Problem is, floating projects are technically demanding and expensive, with a cost of up to twice that of onshore wind. HYDROELECTRIC Roughly 7% of the energy consumed by Japan in 2010 came from hydroelectric sources, which presently have a max output capacity of 48 GW. The Ministry of Economy, Trade, and Industry estimates that it may be feasible to add up to 12 GW of additional capacity through new development—though because most of the big dam sites in Japan are already dammed, added capacity could come only from smaller hydro projects that would cost more per kilowatt hour. BIOMASS Japan is tops in the world at creating power from municipal solid waste, consuming 40 million tons per year. Currently, there are 190 waste facilities that have biomass generators and 1,900 that don't, so there's plenty of opportunity to add capacity. But biomass plants have recently struggled due to a shortage of thinned wood and chips, which are a necessary part of the burning process. In 2009, a third of biomass plants were forced to cease operations because of the shortage.
Illustrations by Matt Owens