Sixty percent of the nation's large thermal power plants are situated in areas at risk of a major earthquake, a disturbing finding given Japan's growing reliance on this technology in the aftermath of the 2011 nuclear disaster.
Sixty percent of the nation's large thermal power plants are situated in areas at risk of a major earthquake, a disturbing finding given Japan's growing reliance on this technology in the aftermath of the 2011 nuclear disaster.
The Asahi Shimbun studied 64 thermal power plants, each capable of generating 1 gigawatt or more, based on a ground motion hazard map updated in December by the Headquarters for Earthquake Research Promotion.
The map charts the probability of an earthquake measuring lower 6 or stronger on Japan’s seismic intensity scale of 7 within the coming 30 years.
Earthquakes of such strength can cause substantial damage to buildings as well as loss of life.
Forty thermal power plants, or 63 percent of the total, are located in areas with a probability of 26 percent or more. Of those, 33 are in areas with a probability of 50 percent or more.
By region, all 18 plants in the Kanto region, all nine plants in the Tokai region and all three plants in Shikoku are located in areas with a probability of 26 percent or more.
Seven of the 12 plants in the Kinki region, two of the five plants in the Tohoku region and one of the seven plants in Kyushu are located in such areas.
Many are situated on the Pacific side of Japan, which is considered particularly vulnerable due to predictions of an offshore earthquake striking along the Nankai Trough, which stretches from Suruga Bay off Shizuoka Prefecture to waters off Kyushu. There are also fears that a major earthquake will occur directly beneath the Tokyo metropolitan area.
Japan’s dependence on thermal power has risen to 90 percent because nuclear plants were shut down after the Fukushima nuclear disaster in March 2011. Only the Oi nuclear power plant in Fukui Prefecture has been restarted.
The government says thermal power plants are earthquake-resistant. But some experts suspect that aging facilities brought back online after the nuclear accident are vulnerable to temblors and tsunami.
The March 2011 tsunami damaged power generation and fuel storage facilities at a thermal power plant in Hirono, Fukushima Prefecture, and another in Tokai, Ibaraki Prefecture. It took more than two months for the plants to resume operations.
Japan also has 28 terminals for liquefied natural gas. Sixteen of them are located in areas with a 30-year probability of 26 percent or more for an earthquake of at least lower 6. Nine are in areas with a probability of 50 percent or more.
Of the nation’s 17 nuclear power plants, four are located in areas with a probability of 26 percent or more. They are the Hamaoka plant in Shizuoka Prefecture, the Fukushima No. 2 plant in Fukushima Prefecture, the Onagawa plant in Miyagi Prefecture and the Tokai No. 2 plant in Ibaraki Prefecture.
The Oi nuclear power plant is located in an area with a probability of 0.1 percent.
All but one of Japan's nuclear power plants remain shut down.
(This article was written by Takashi Sugimoto and Senior Staff Writer Tairiku Kurosawa.)