Unfortunately I was wrong about the likely death toll from the reactor outage at Fukushima Daiichi.
There's a very good chance that it's going to kill thousands of people — possibly more than the earthquake and tsunami combined.
But the cause of death won't be the one you're probably thinking of.
Western Japan and Eastern Japan do not share an electricity grid; because of an historical accident, in the 1890s when they were first getting electric lighting, Osaka, in the west, chose to run at 60Hz and Tokyo, in the east, picked 50Hz. Consequently there's no grid interconnect between the two halves of the Japanese electricity supply system.
Eastern Japan has had 15 nuclear reactors scrammed by an an earthquake. Some of them may be checked out and approved to start delivering base load again over the coming months, but they all need a thorough inspection at this point — and we know for sure that at least three of them will never work again (not after they've had seawater pumped through their primary coolant circuit).
We are now heading into summer. And Tokyo doesn't have enough electricity to maintain power everywhere even in spring.
Summer in Tokyo is savage: temperatures routinely top 35 celsius with 100% humidity. In a heat wave, it can top 40 degrees for days on end. Back when I visited in late August of 2008, the heat wave had broken and daytime temperatures were down under 37 degrees again — the week before it had been over 42, and joggers had been dropping dead in the street.
Greater Tokyo also has 30-million-odd people, of whom a large proportion — maybe 20% — are 75 years or older.
Elderly folks do not handle heat waves well; they get dehydrated easily and if they don't have air conditioning they die in droves. Normally it's not a problem in Tokyo because 80% of households have air conditioning, but with rolling blackouts and insufficient power it's another matter. They can try and evacuate old folks into school gyms with aircon and portable generators, but the logistics of moving several million geriatrics are daunting, to say the least. Not to mention feeding them, keeping them hydrated, providing their medication, and handling sanitation.
If TEPCO can't get some of those 15 reactors back on stream by June, and if Tokyo experiences a heat wave this summer (as happens every few of years), then going by previous incidents (like the heat emergency in Paris in 2003 that killed 3000 people) the deaths from heat stroke, among the other-75s may rival the direct fatalities from the earthquake and tsunami combined.