The Sendai mega-earthquake not only sent a tsunami of water over parts of coastal Japan, but also one of hysteria over the German media and green establishment. As Japan struggles to get a grip on its damaged reactors, German environmentalists are seizing the opportunity in a bid to fan panic across the country, and are now demanding that the country’s older reactors be shut down immediately. The voices of calm reason have been swept away.
The blog Denken für die Freiheit (Thinking for Freedom) of the Liberal Institute think tank of the Friedrich Naumann Foundation for Freedom has posted a let’s-get-back-to-reason essay – Japan is not the Soviet Union – written by Dr. Klaus-Dieter Humpich. Here’s a summary:
Dr. Humpich first reminds us that Japan is subject to international regulations and so are reporting minute by minute on what is happening at the reactor sites. All planned and executed measures are reported to the public. Indeed the confusion is often media-related.
Reserve generators for cooling failed
When the earthquake struck, 3 of the 6 Fukushima Daiichi reactors were in operation, and stopped automatically – as they were designed to in the vent of an earthquake. Then diesel-powered back-up generators kicked in to supply power to the cooling water pumps. But within one hour, the diesel-powered generators failed due to yet to be determined reasons. Workers then brought in reserve generators, and it appears there were then problems in getting them in operation. During this time the cooling of the rods was not taking place and this led to overheating. This will certainly be examined later when a comprehensive investigation of the disaster begins.
In the reactor, heat and pressure build up if cooling doesn’t occur – like a pressure cooker on a hot stove. If pressure is too high, then steam has to be released into the atmosphere to keep the reactor from exploding. But then an equal amount of water has to be fed in in order to keep the balance. If the level of the water sinks too low, then things inside get hot. Once a critical value is reached, a chemical reaction between the steam and hydrogen can occur. At the Fukushima reactor on Saturday, hydrogen built up and an explosion ensued. Yet, the containement systems were left intact.
Japan’s containment systems not breached
But the situation in Japan developed completely differently from what happened in Chernobyl in 1986. In Japan, the reactors were shut down immediately as planned, thus stopping the nuclear reaction. At Chernobyl, the reactor was operating a full capacity and spiralled quickly out of control.
With the shutdown of the Fukushima reactors in response to the quake, only about 10% of the capacity still remained in the reactor. The cooling system powered by the diesel pumps then functioned for an hour, and so the heat generating capacity of the core was brought down to about 1% of total capacity – much less than Chernobyl. Although 1% still means one megawatt, it is not enough to blow the entire reactor and containment. In Chernobyl the chain reaction ran away and the entire reactor vessel and containment building exploded violently, releasing everything into the air. That’s not the case in Japan.
At Fukushima, the reactor vessel, the containment and external concrete housing are still in intact. This means there are still three barriers that would have to be breached before dangerous levels of radiation can escape.
Category 4 accident (TMI 5, Chernobyl 7)
As the reactors are still heating, there’s naturally the risk of high pressure build-ups, which could lead to a Chernobyl type of explosion if not relieved. To prevent a failure of the containment building in an emergency, radioactive steam would have to be released though a filter system into the atmosphere in a controlled manner. .This rersults in a radioactive cloud. A controlled release is relatively not very dangerous as it dissipates quite rapidly. That’s why the accident at Fukushima is at Category 4 (TMI 5, Chernobyl 7). Category means that the reactor is totally damaged, but there is little impact on the surrounding environment. So we are still a ways away from Chernobyl.
Risk not completely eliminated
Although the containment systems are intact, the heat problem is still not eliminated. Sea water still has to be pumped to the damaged reactors to prevent heating and overpressurization. If the reactor has no water to keep cool, the temperatures can rise and lead to a meltdown. The latest news is that three reactors are threatened with a meltdown. The cooling water around the fuel rods in Reactor 2 have dropped dramatically.
The next hours and days ahead will show if the plant will withstand the 9.0 quake.
In the meantime, a panicked Chancellor Angela Merkel, spooked by the media hysteria, has announced that the planned extension of the operating lifetime of some of Germany’s older nuclear plants has been stopped. I wonder if India, China, Brazil and Iran will follow her example and abandon their ambitious plans to build a number nuclear power plants in the future.