Clive Cookson breaks down the situation at Japan's Fukushima plant and the implications for the future of the nuclear industry.
How serious is the partial meltdown at Japan's Fukushima plant?
It is certainly alarming and sure to have grave implications for the nuclear industry and energy sector as a whole – but far from being another Chernobyl, where a runaway nuclear reaction blew the top off a rudimentary containment system.
The three operational reactors at the Fukushima Daiichi power station shut down automatically as planned when their motion sensors felt tremors from the magnitude 8.9 quake on Friday. But multiple cooling systems, required to remove heat from the core, failed. The tsunami soon knocked out the backup diesel generators that were pumping cooling water around the core. Batteries kept the circulation going for another few hours until they ran flat.