Hi, Dr. Zoomie – I heard in the news today that Bill Gates is investing in nuclear reactors. That got me curious so I started reading about them. There’s a lot out there, including some of your pieces, that talk about reactors being pretty safe, but then I remember the accidents at Three-Mile Island, Chernobyl, and Fukushima and it just makes me wonder. And I know that mining uranium is dangerous too, and all the radioactive waste. Anyhow, I’m wondering if you can tell me how safe nuclear energy really is, compared to the other kids of energy production.
Wow – there’s a lot to unpack here – let’s see:
- Why is Bill Gates investing heavily in a nuclear reactor?
- How safe are nuclear reactors themselves?
- How dangerous are reactor accidents?
- How dangerous is uranium mining?
- How does nuclear energy compare to other forms of energy production in terms of safety?
Why is Gates interested in nuclear energy?
Climate change, plain and simple. Gates has been concerned about climate change for at least a decade and he’s come to see it as one of the biggest challenges facing humanity – if climate predictions are accurate then the spread of tropical disease, flooding of coastal cities, and increasing numbers of stronger storms will place tens or hundreds of millions of people at risk, will kill millions of tens of millions, and will cost trillions of dollars. On the other hand, reducing energy production will also cost lives and will strand hundreds of millions of people in the developing world in lives of hardship and poverty. Gates (and others) sees nuclear energy as the best way to give the world the energy it needs without adding further to the climate change that’s taking place.
At the same time, Gates also recognizes that the current nuclear energy paradigm – huge, and hugely expensive gigawatt-sized reactors – have their own issues: cost, complexity, and the use of high-temperature water at high pressures to keep the core from melting down. The reactor that Gates is putting his money on sidesteps these by being a smaller, simpler, and less expensive design that uses liquid sodium at near-atmospheric pressure as a coolant. Gates is hoping that this variety of small modular reactor (SMR) will be able to power small communities that are currently burning coal, oil, or natural gas – and to do it all affordably. If the first plant is a success Gates hope it will become part of the new paradigm for nuclear power.
How safe are nuclear reactors? And what about reactor accidents?
I think it’s interesting to note that there have so few serious nuclear reactor accidents in the 80 years since the first reactor went critical that we can count them all on our fingers: Windscale, SL-1, Three Mile Island, Chernobyl, Fukushima – oh, and a research reactor in Yugoslavia. Windscale caused no deaths from radiation sickness and maybe as many as 240 deaths from cancer in the decades following the accident. The SL-1 accident caused three fatalities; Three Mile Island caused no deaths in the short or the long term (neither did Fukushima), and thus far few than 100 deaths can be attributed to Chernobyl.
Compare this to the cost of coal mining –America’s Appalachian coal fields alone experience 2000-3000 mining-related deaths annually. One of my colleagues was almost one of these deaths – he called in sick for work in a coal mine one day; because he wasn’t there his crew had too few people to be sent into the mine, missing a tunnel collapse that would have killed them all. There are also deaths in the world’s oil fields and refineries, more due to transporting coal, oil, and natural gas around the world, and more; globally, when we total these and add in the effects of air pollution, fossil fuels are thought to cause more than 5 million lives annually.
And uranium mining?
Any form of mining has risks and mining is estimated to be responsible for about 8% of the world’s fatal accidents – as many as 12,000 deaths annually, as many as 80% of which occur in China. I visited an open-pit gold mine several years ago and watched them blast an acre of rock to a depth of 35 feet using over 80 tons of ANFO (ammonium nitrate and fuel oil), nearly 30 times the amount used in the 1995 Oklahoma City bombing. The mine had a number of safety precautions in place and nobody was injured in this blast – but the fact remains that any blast of this magnitude is not without risk, and this is only one small aspect of mining. The greatest risk to uranium miners, though, appears to be lung cancer from inhaling radon along with rock dust, and diesel fumes, along with other cancers present at somewhat less elevated rates. Having said that, the overall mortality ratio for uranium miners compared to the general population was about 1.05 – 5% higher than expected with the risk of lung cancer almost double the risk in the general population; the highest ratio, however, was in silicosis from inhaling rock dust. The bottom line is that mining is a dangerous job – uranium mining involves one risk (radon inhalation) that’s different from other forms of mining, but it’s no more dangerous than most other forms of mining, and (globally) quite a bit safer than coal mining.
And how does nuclear compare to other forms of energy in overall risk?
As far as safety goes, nuclear energy stacks up fairly well with a fatality rate of about 0.03 deaths from all sources for every TWhr of energy produced, compared to 2.8 for natural gas, 18.4 for oil, and a staggering 24.6 for coal. Solar is slightly safer, wind is slightly higher (hydropower is skewed by a 1975 Chinese dam failure that killed over 170,000). For nuclear energy, this includes deaths from uranium mining, building and operating the reactor plants, shipping radioactive waste, and everything else – including the accidents we’ve experienced.
The bottom line is that, while nuclear energy has its risks, even when we add in the risks from uranium mining and the rare nuclear reactor accidents, they’re more than order of magnitude lower than the risks of fossil fuels and are comparable with the risks from alternative sources of energy.
Image Reference:
The Header Image for this article was cropped from an image of the United States Secretary of Health and Human Services Alex Azar and Bill Gates on March 14, 2018. The author of this image is the United States Department of Health and Human Services. This image is a work of the United States Department of Health and Human Services, taken or made as part of that person’s official duties. As a work of the U.S. federal government, the image is in the public domain.