Don’t tell anyone I said so but the lights are still on in Tokyo. Unremarkable, you might think. But two-thirds of Japan’s nuclear power stations are switched off. Sweltering summer temperatures are well into the 90s Fahrenheit, putting further strain on the depleted energy supply. If nuclear power is really as vital to the Japanese economy as has been made out, how come the country has not ground to a halt?

Nuclear energy normally accounts for 30 per cent of Japan’s electricity needs. Before the March earthquake and tsunami caused the worst nuclear crisis since Chernobyl, the idea had been to raise this to 50 per cent by 2030. That would have meant adding at least 14 new reactors to the 54 already in operation.

Now Naoto Kan, the prime minister, has suggested Japan should phase out nuclear power altogether. The public, concerned about post-Fukushima radiation in the air and in their food, appears to support him. Depending on how the question is put, polls show 70 per cent or more Japanese now oppose nuclear power. Of course, if you asked “do you enjoy sitting in the dark?”, the response might be different.