nuclear-news

How the nuclear industry avoids a proper safety analysis

The Nuclear Industry’s Really Bad Safety Analysis, Clean Technica. December 31st, 2020 by George Harvey 

Before we allow small modular reactors, mini reactors on barges, reactors for making hydrogen, reactors to be set up on the Moon, or just about any nuclear reactors to be built, we should get an explanation from the nuclear industry of why some of its calculations have been so bad. I am talking about numbers that are so bad, off by an order of magnitude, that they are functionally deceptive. And if they are not intentionally deceptive, that is not an excuse. They fool people into thinking things are true when they are not, and they are very much to the advantage of the nuclear industry.

In my experience, nuclear industry numbers come in three flavors. The first of these is just about spot-on, just about 100% of the time. These numbers relate to such things as calculations of energy potentials. If a company says a reactor can provide 1,000 MW of power, you can count on it that the output of that plant will be 1,000 MW.

There is a second type of calculation that the industry provides. This relates to the costs and timelines for construction of new reactors. Calculations in these areas seem to underestimate both by about half. If the figure for a new reactor is $5 billion and its construction is to take 5 years, I would figure on a $10 billion cost and a 10-year timeline. I acknowledge that I have not done a careful study of this, but I have often noted that real world results that were double what was estimated, and I only remember one that was correct. (I am speaking of US and UK reactors here, not those that are built in China, with which I am much less familiar.)

It is the third type of number that really bothers me, however, and this is something I have studied since the Fukushima Disaster. For some purposes regarding safety, the industry numbers are off by an order of magnitude, with its calculations appearing to make the reactors ten times as safe as they are.

I admit that some safety numbers are controversial. There is huge disagreement about how many people died as a result of the Chernobyl Disaster, for example. I will start with that.

got an email some time back from a nuclear industry advocate. In it he said the explosion of a reactor at Chernobyl proved that nuclear energy was safer than coal or other fossil fuels. I will grant you that our use of coal has caused a large number of deaths, both in the mines and among the general public. But the email was revealing in its very specific number. How it was calculated, I don’t know, but the figure given was 17 deaths.

Though that was the lowest I have seen, other figures from nuclear advocates are equally specific. A list at Wikipedia says provides the old Soviet Union’s official list of 31 people who were killed. I have seen that figure used recently. Elsewhere in the same article, however, it is stated that a total of 60 people died, according to a later source, including later deaths of radiation-induced cancer. Again, the same article speaks of UN estimates of 4,000 people who might have died of health effects in the Ukraine, Belarus, and Russia, with a total of 16,000 when other parts of Europe are factored in, and maybe as many as 60,000 when worldwide effects are considered. Greenpeace has projected death tolls possibly going up to a million.

So what are we to believe? To answer that question, I will say we should not believe any specific figure, but instead note that the low figures from the nuclear industry and the high figures from anti-nuclear activists differ by over four orders of magnitude.

I would also note that the figures from the nuclear industry are not believable, because they do not even admit the possibility of more deaths than the low numbers they specify. And I will not say the high figures are unbelievable in quite the same way, though I would not believe them just because they come from Greenpeace. The point is that the differences themselves are disturbing…………..

The Fukushima Daiichi plant was protected by a 5.7 meter (18.7 feet) sea wall. The Tohoku tsunami that hit it, which arose from the most powerful earthquakes ever recorded in Japan, was 14.5 meters (47.6 feet) tall at the plant. To get a grasp on what this means, remember that a tsunami of this type is not an ordinary wave that quickly crashes and withdraws, it is a rise in the water level than keeps going on for a period of time, possibly several minutes. So for a period that must have felt terrifyingly long to those who witnessed it, water kept rising until it was nearly 8.8 meters (28.9 feet) higher than the sea wall. Videos of the Tohoku tsunami show the effect.

The nuclear industry’s response to this could be summed up in the question: Who could have predicted such a thing? But that fails utterly to recognize some facts. The sea wall was clearly too low, based on the region’s history.

To start with, the earthquake was the most powerful on record, but the records only go back to 1900. The 14.5-meter wave at Fukushima Daiichi was not the highest that the tsunami produced. The highest wave it had was 40.5 meters (133 feet) in Iwate Prefecture. But we should recognize this was not really the unique event it seemed. Limiting our look to other tsunamis on the northeastern coast of Japan, we could count the 1896 Sanriku Earthquake, which had waves of up to 30 meters (100 feet), and the 1933 Sanriku Earthquake, which had waves of up to 28.7 meters (94 feet).

Both of these events happened less than 100 years before the Fukushima power plant was designed in the early 1970s. They should have been taken into account for construction of sea walls. In fact, they were taken into account for building a 15.5-meter (51 feet) flood gate at Fudai, Iwate, a village of roughly 2,600 people. The waves were higher there than at Fukushima Daiichi, but they barely topped the flood gate, and no one it protected was killed.

So why did Fukushima Daiichi have a 5.7-meter sea wall? I would say it was clearly a matter of human failure. Though I have to admit that reality might have been very different, I can picture someone walking into a room with a group of engineers in it, and asking how tall the sea wall was going to be. And the answers comes back as a question, “What is the budget?”

I have never seen the nuclear industry address the question of why their safety analysis calculations are off by an order of magnitude. Until they do, and I think it should include a gigantic mia culpa, my own choice would be not to allow any of their fantastical designs to be built.  https://cleantechnica.com/2020/12/31/the-nuclear-industrys-really-bad-safety-analysis/

January 2, 2021 Posted by Christina Macpherson | 2 WORLD, safety | Leave a comment