TOKYO—The Japanese government's minister in charge of national strategy said a new generation of smaller nuclear reactors might be the answer for a country traumatized by the March Fukushima Daiichi crisis, at a time when much of the nation is looking toward a nuclear-free future.
National Policy Minister Koichiro Gemba—who is responsible for helping craft energy policy—said that despite the bitterness following the accident at the nuclear-power plant, Japan should consider the use of what are known as microreactors, as a way to help bridge the electricity shortages that plagues the industrial sector.
"The development of microreactors isn't incompatible with the goal of achieving a more distributed power supply," Mr. Gemba said in a recent interview with The Wall Street Journal.
His push for smaller reactors comes as Japan grapples with the realities of Prime Minister Naoto Kan's antinuclear push. Mr. Kan scrapped the previous strategy that called for a near doubling in nuclear power to more than 50% of Japan's total electricity generation by 2030. But while a shift away from nuclear power has gained popular support, Japan has little in the way of domestic deposits of coal, natural gas or oil to meet its power needs, and alternative-energy solutions appear inadequate. Mr. Kan also is expected to resign in coming weeks, making his goal uncertain.
Japanese officials have continued to explore nuclear-power options despite opposition to them. A consultative body to Banri Kaieda, the minister who oversees Japan's nuclear-power industry, last month said that abandoning technology under development for smaller nuclear reactors and other alternatives would be a waste.
Keiji Miyazaki, professor emeritus of Osaka University, said smaller reactors have cost disadvantages but are worth considering as part of the future energy mix. Microreactors are expensive to operate because the systems to power a reactor cost about the same no matter the size of the unit. This means that unit costs will be much higher than for the reactors typically used in Japan.
Microreactors are next-generation reactors that generate less heat and are capable of cooling themselves without the use of an external power supply, a key vulnerability in the Fukushima disaster, as the units overheated due to a lack of circulating water. All three Japanese reactor makers—Hitachi Ltd., Mitsubishi Heavy Industries Ltd., and Toshiba Corp.—are pursuing them, Toshiba in particular. The concept, however, is still in the development phase. Toshiba has said it is looking to market such reactors later this decade.
Mr. Gemba said he believes Japan should look to "distributed power generation" where electricity is generated by an interconnected network of small and medium-size producers. The concept is an antithesis to the current Japanese system, which is based on constructing large nuclear plants in remote rural areas to produce electricity for large cities.
The 47-year-old Mr. Gemba—who was born in Fukushima prefecture and represents a district near the stricken plant—said he has based his recommendation on the wave of local complaints that have emerged since the March disaster. He said it is directed more at energy policies set by the central government with little regard for local concerns, rather than at promoting nuclear power. He continues to call for less reliance on nuclear energy.
Since March 11, at least five reactors have been kept from restarting even after their regular maintenance checks were completed, as local communities refused to allow their reopening.
"The newer the reactors are safer," Mr. Gemba said. "The safety of nuclear plants would be improved by replacing older reactors with newer ones.
The three reactors that suffered partial meltdowns at the Fukushima Daiichi are more than 30 years old, with technology developed before the lessons of incidents such as the 1979 Three Mile Island accident. Before the March disaster, the Japanese government saw large-scale reactors as the way to meet an anticipated surge in reactor-replacement demand around 2030.
Microreactors were being considered mainly for overseas markets. An official at Japan's Ministry of Economy, Trade and Industry, which currently oversees nuclear regulation, now says "manufacturers will explore the domestic market if there is demand."
Mr. Gemba didn't offer a projection for the share of nuclear power in the total electricity supply, but noted it will likely be well below the 26% level reached in 2007, often used as a baseline for discussion. He argues that the nation is prepared for a major shift in energy policy, even if it entails higher utility rates and a change in people's lifestyle. Legislation is in the works to introduce German-style feed-in tariffs, which would require utilities to purchase electricity generated with renewable sources at premium prices.
