By The Casey Research Energy Team
The outcome at the embattled Fukushima Daiichi nuclear plant is so important to the future of nuclear power that we thought an update would be in order. The long and the short of it is that Tepco is making progress, but oh so slowly.
Fukushima has now earned the same nuclear disaster severity ranking as Chernobyl, though experts continue to stress that the two situations are very different. Fukushima’s severity ranking crept up to seven out of seven as it continued to seep radiation for weeks, and as Tepco gained a better understanding of how much radiation leaked out in the first few days of the disaster. Japanese officials stressed that the severity upgrade does not mean things are getting worse.
Temperatures in all six reactor buildings are now below 200°C, down from highs of 1,000°C in the worst days following the earthquake and tsunami. Reactors 5 and 6 are in the best shape and are now considered stable. However, robots sent into the buildings around Reactors 1 and 3 sensed radiation levels too dangerous for humans, even for a short period.
In the No. 1 reactor building a robot detected radiation levels as high as 49 millisieverts per hour, while in the building around No. 3 a robot measured 57 millisieverts per hour. Exposure totalling 100 millisieverts over a year is the lowest level that can cause increased cancer risk, according to the World Nuclear Association. No one has been in what remains of the buildings around Reactors 1 through 4 since the tsunami hit.
In a major step forward, Tepco announced a timeline for its efforts, saying it plans to reduce the radiation levels at Daiichi significantly within just three months and then bring all six reactors in to cold shutdown within nine months. Those may seem like long timelines, but it takes a long time to cool (and therefore slow down) a nuclear reaction. In addition, having already lost 80% of its market cap in just over a month, Tepco certainly does not want to fail on its timeline targets, so it is likely managing expectations to a certain degree.
To achieve a sustained drop in radiation, Tepco plans to fill the reactor containment vessels at Units 1 and 3 with water. It will do the same with Unit 2 once it is able to get close enough to the containment vessel to repair the breach it sustained when the building housing the reactor exploded.
Repairing the breach in Unit 2 and switching to filling the containment units with water will help Tepco in another important way. To keep the reactors cool the company has been spraying them with hundreds of tons of water daily, but all that slightly radioactive water ends up in basements and drainage trenches, where it can leak into the groundwater or the ocean. Cleaning up and containing the radioactive water is very difficult, especially because the contaminated water tanks at the plant were almost full before the disaster struck. Tepco is already working to build additional tanks, but shifting the cooling process to a closed loop system will help even more.
Once the containment units are filled with water, they will be left to cool for several months. In the meantime the company plans to erect covers over the No. 1, 3, and 4 reactor buildings, as a temporary measure to reduce radiation emissions. Three to six months later Tepco will attempt a cold shutdown of Reactors 1, 2, and 3 (Reactors 4, 5, and 6 were shut down when the earthquake hit). A cold shutdown is when the reactors drop below 100°C, so the water trying to cool the rods is below boiling. That allows operators to de-pressurize the reactors.
Only then – nine months after disaster struck – will the families evacuated from the Daiichi area know whether they can return home.
As for when uranium prices will return to their pre-Fukushima levels, that may take even longer. We are not even going to try to table a timeline for uranium’s recovery, but we will say this: we still believe nuclear power will play a key role in providing the world with energy, especially in rapidly developing countries like China and India. That means we still believe in uranium in the long term.
In the short term, we just have to remind ourselves that there is no quick fix for damaged nuclear reactors, so Fukushima will stay in the headlines for some time. Those headlines were revived this week as Russia, Ukraine, and Belarus marked the 25th anniversary of the Chernobyl calamity. On a visit to the decommissioned reactor, Russian President Dmitry Medvedev called for new international rules governing safety at nuclear plants, saying such rules would enable the world to move ahead with the "necessary" development of nuclear energy. He did not provide any specifics.
And we send our thanks to the 240 or so Tepco employees who have been living on site since the crisis began, working long hours in dangerous conditions and spending their nights in a radiation-proofed concrete bunker, doing their all to contain a calamity.