This is part of IEEE Spectrum's ongoing coverage of Japan's earthquake and nuclear emergency.
3 May 2011—As the battle drags on to stabilize the three crippled reactors at the Fukushima Dai-1 nuclear plant, arguments are heating up among energy experts on what Japan ought to do about securing its future energy needs. Three experts involved in creating energy policy or nuclear safety standards debated the question on 25 April at the Foreign Correspondents’ Club of Japan, in Tokyo, and they had little to agree on.
Keiji Miyazaki, professor emeritus at Osaka University and a specialist in the study of severe accidents, strongly defended the need to continue using nuclear energy. He called it "indispensable for Japanese industries and for solving the 3E trilemma: energy security, economic growth, and environmental protection."
Miyazaki argued that light water reactors produced the highest energy-profit ratio (EPR)—a ratio of energy output to input—at 17.9, compared with power plants using oil and coal with EPRs well under half that figure. Solar and wind power were even lower, and liquefied natural gas was the lowest, with an EPR of just 2.14. He also said that for cost per kilowatt-hour, nuclear energy achieved the lowest figure with a cost of 5.3 yen, compared with coal at 5.7 yen and oil at 5.8 yen, while solar energy was the most expensive at 49 yen (1 yen currently equals 1.2 U.S. cents). (Miyazaki’s figures are based on data from the Central Research Institute of Electric Power Industry and the Federation of Electric Power Companies of Japan.)
"Solar [and wind] energy requires vast areas of land and large-scale storage systems to replace nuclear energy: 4000 square kilometers to replace the 50 gigawatts of energy produced by nuclear energy," said Miyazaki, using his own calculations. "[In Japan,] to replace a 1-GW nuclear plant, a 6- to 7-GW solar PV plant is necessary [given fluctuations in output]. So large-scale solar is not suitable for Japan, because land prices are very high."
But another panelist, Atsushi Kasai, former laboratory chief of the Japan Atomic Energy Agency, pointed out that the figure of 5.3 yen per kWh for nuclear generation did not include "the cost of radioactive waste management and disposing it." One reason was that waste handling "did not come within the providence of the power companies, but rather was [considered] the responsibility of the nation, the national government." He added that he has always been against this way of calculating costs and has argued that the cost of waste disposal should be included in the figure.
Tetsunari Iida, executive director of the Institute for Sustainable Energy Policies, an independent nonprofit research organization in Tokyo, described the 5.3 yen figure as "completely nonsense," saying that the Ministry of Economy, Trade, and Industry, which was responsible for publishing the figure, had refused to divulge the data the figure is based on. Iida, who argued for a gradual reduction and eventual curtailment of nuclear energy use in favor of investing in and building up renewable energies, added that in light of the Fukushima accident, all the power companies should contract with insurance companies to get unlimited insurance coverage, although he doubted that such an insurance existed. "If you consider decommissioning costs and the unlimited liability costs that TEPCO [Tokyo Electric Power Co.] must pay for this accident, the cost [for nuclear energy] might be tripled," Iida said.
Miyazaki countered that the 5.3 yen figure was provided to give "a sense" of what the different energy-generation costs were and that it did indeed include the cost of reprocessing spent nuclear fuel and decommissioning a plant under normal circumstances, although not the cost of waste disposal.
Miyazaki went on to say that if power companies invested sufficiently in safety, then nuclear power plants could be built to withstand earthquakes and tsunamis. "The problem is that although utility companies say ’Safety first,’ in reality they want to hold down costs whenever they can," he said. "If you look at the [Fukushima] Number 1 [the troubled reactor complex called Fukushima Dai-1] and Number 2 [a nearby sister complex that survived without major problems] plants, the results are very different, and this is partly a consequence of how much money was spent on building these power plants."
One point on which Kasai sided with Miyazaki against Iida was that wind and solar were not the answer to Japan’s future energy needs, given the vast amount of land that would be required. Rather, Kasai favored the best possible combination of existing power-generation systems and the promotion of geothermal power.
"Japan is a volcanic country, so why hasn’t its energy policy taken into account geothermal energy?" Kasai asked. "Why hasn’t more research been done? It may be that it cannot meet all the energy needs; however, it should be a part of energy policy."
Miyazaki responded that there were some efforts going on in geothermal regions. But while some areas were energy rich, he said, others weren’t, "so if geothermal plants were built, they would only produce tens of thousands of kilowatts." He also noted that the many hot-spring hotel owners in the geothermal areas were against the idea, worrying that such plants might deprive them of their use of the hot springs. "If you want to do more research in this area, fine," said Miyazaki. "But I don’t hold out any great expectations."
About the Author
John Boyd is a Tokyo-based technology and science journalist. He has been covering the ongoing nuclear emergency in Japan since the 11 March earthquake.