Two power companies owned respectively by billionaires Bill Gates and Warren Buffett have chosen the site of a retiring coal power plant as the likely site for an experimental nuclear power plant. Gates’ TerraPower and Buffett’s PacifiCorp hope that the location of the new reactor will be confirmed by the end of the year, and the potential site was announced during a press conference in Wyoming.
The Natrium reactor is a molten sodium nuclear fission reactor, similar to the ones being built in China that are at the center of international concerns. The reason is that such reactors produce more radioactive material than they consume, and among such products there’s plutonium. Plutonium can be used in other nuclear reactors or countries can decide to use it for nuclear weapons. These types of reactors are known as fast reactors.
The production of plutonium in itself is not dangerous – how it is employed is more of concern. The reason why there is an interest in these reactors is the efficiency. The vast majority of nuclear reactors use water to cool down the reactions, and this approach can extract less than one percent of the energy from uranium.
In an ideal molten salt reactor, the efficiency is 100 times higher. That means a smaller reactor with less fuel for much higher energy output. For Natrium and similar approaches, efficiency is not going to be as high, and in the long term this can only be achieved with the spent fuel being reprocessed and recycled
Analysis from the Union of Concerned Scientists also highlights concerns about the safety of the reactor, given the reactivity of dealing with molten sodium, as well as risks with the proliferation of nuclear devices as such reactors have longer and more complex production chains. Fast reactors have certain advantages if done well and they can be crucial in reducing greenhouse emissions, but there’s definitely a need for addressing some of the outstanding issues.
This reactor is expected to produce 345 megawatts, which can be increased to 500 megawatts for more than five and a half hours when demand requires. That’s equivalent to covering the energy requirements of 400,000 homes.
At the moment, there are two commercial fast reactors in Russia and two test reactors in India and Japan. The Chinese ones are expected to begin operation in 2023 and 2026, and this new US one would begin working towards the end of the decade.