An article in this week's Sunday Mainichi implies that Tokyo Electric Power Company's series of planned blackouts in the Kanto region to address power shortages as a result of the failure of the Fukushima nuclear reactors is a kind of demonstration, the point of which is to show customers that they really need those nuclear reactors, even if they are on the verge of rendering the Tohoku region radioactive. Though the article's tone is cynical, anti-nuclear forces have been accusing Tepco of essentially the same PR strategy for years. Faced with another serious power shortage in 2003, Tepco threatened blackouts unless customers cut back after the company was forced to shut down reactors for emergency inspections in light of a safety scandal.
Electricity users in the Kanto region are already dealing with periodic power outages to save energy, and because we're doing as we're told, some planned outages have been canceled. The problem with generating electricity over a conventional power grid is that once you generate it you can't recover any that isn't used. And unlike thermal generators that use fossil fuels, nuclear reactors cannot be turned up or down at will. Once they are operating it takes months to turn them off. Tepco's output is basically a blend of constant nuclear power and fluctuating thermal and other forms of power generation. The 10 Fukushima reactors provided 14 percent of Tepco's power, about 50 million kilowatts.
Average power consumption at any given moment during March in the Kanto region is estimated at 47 million kw. This is far less than the 65 million kw that are normally consumed during the peak days of summer, when air conditioners are on, but last Monday, when Tepco launched the planned blackouts, the maximum output available was 31 million kw, so Tepco had to convince homes and businesses to use less than that. If they didn't, they would have to cut power to the designated "groups."