Thursday, January 13, 2022

A New Look at Nuclear Power

 James Hansen is probably the most well-known climatologist in the world. Bill Gates is the founder of Microsoft and author of “How to Avoid a Climate Disaster”. They both think that nuclear power is the surest path to “decarbonizing” electric power generation. Neither think that solar and wind technology will be sufficient to achieve that goal because of their intermittent nature. Many scientists and engineers disagree with that assertion, but that’s a discussion for another day.

I think nuclear power is a great idea, but I also think that in its current incarnation, nuclear power won't do the job. The majority of the world’s nuclear power plants are pressurized water reactors. They are expensive, take years to build, are complicated and labor intensive to maintain, and if something goes wrong, it can go very, very wrong. In short, they are money-losing propositions compared to natural gas and oil-fired power plants and in the last few years, commercial-scale wind and solar.

However, the recently passed $973 billion Infrastructure Investment and Jobs Act contains two provisions which focus on nuclear power.

First, it contains $6 billion for the Civil Nuclear Credit Program, which will provide 4 years of subsidies to nuclear plants that are economically uncompetitive and otherwise likely to shut down. It’s a tacit admission by the Federal Government that the nuclear power industry cannot survive on its own.

Second, the act contains $3.21 billion for small modular and advanced nuclear reactors (ANRs). Conceptually, ANRs will have the virtues of nuclear power, with many fewer of its vices.

ANRs by definition need to produce less waste, have more safety measures to prevent meltdowns in case cooling systems fail, and provide greater reliability. They need to use a modular design so they can be built, deployed and certified in less time. ANRs need to be smaller so that they can be used to power industrial facilities such as smelters and smaller communities, or combined to create large electric power generation facilities. Last they need to be more responsive to rapid changes in grid energy demand.

Startup companies such as NuScale, TerraPower, and X-energy have ANR designs on the drawing board. They are getting funding for construction of pilot plants via the infrastructure act and private investors (Bill Gates is backing TerraPower). Each company’s approach is different. I won't get into the nuts and bolts of their technology because this is a local newspaper, not an engineering journal.

NuScale and X-energy have already submitted applications to the Nuclear Regulatory Commission. Their reactors are small enough to be built in a factory. According to The Atlantic, NuScale, with US Government support, will soon install five reactors in Romania as well as one in Wyoming. TerraPower is going to build a pilot plant in Hanford Washington.

The ANRs I have discussed above are fission reactors. They split atoms of Uranium-235 to generate energy. But there is another type of reactor that falls into the ANR category – a fusion reactor. Unlike fission, fusion reactors fuse Deuterium (an isotope of Hydrogen) into Helium, the same process that powers the sun.

And therein lies the problem. Fusion requires maintaining a sustained temperature of over 100 million degrees C. Until recently, the only way to do that is at the center of a detonating nuclear bomb. Needless to say, the idea is to power a city, not blow it up.

Since I was a child, fusion power has always been 40 years away. The technology to safely create and contain such extreme temperatures was always beyond our engineering capability, but not anymore. The problem now is to get more energy out of the reactor than it takes to maintain the reaction.

Experiments to create sustained and controlled nuclear fusion have been so expensive that only governments can fund such endeavors. ITER, in France, is funded by 35 nations and costs $25 billion. The reactor weighs 23,000 metric tons and is 240 feet tall.

Seventeen private companies are attempting this feat on a much smaller scale. They have about $2.4 billion in funding, according to the journal Nature. The reactors have names like Mini-Tokomak, Colliding Beam, Magnetized Target, and Stellerator. Sizes range from a single family house to a large high school gymnasium.

Instead of 40 years away, the ever-shifting timeline to commercial fusion is now a 10 to 20 years away. It still doesn't mean we are close.

I’d like to see any of these technologies succeed, because current nuclear power technology, dating back to the late 1940s, is way past its expiration date from an engineering and economic perspective. It cannot meaningfully contribute to a decarbonized energy future. Maybe ANRs can.

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