"I am not counting on fusion to contribute any meaningful contribution to decarbonization within the next few decades"
- Isabelle Boemeke

Why do you feel Nuclear Fission (instead of Fusion) is so important for the human race as an energy source?

Nuclear power is a proven technology that has been successful at decarbonizing grids as best exemplified by France. In the 1970’s during the oil crisis, France decided to become energy independent. They built 48 reactors in 18 years and drastically reduced their reliance on fossil fuels for electricity generation. Today France's carbon emissions per kWh are lower than Germany, the UK and Denmark. The country also has some of the cheapest electricity in Europe.Nuclear fission (splitting atoms to create energy) is already here, works at large scale and can help us decarbonize today!

Nuclear Fusion (smashing atoms together) on the other hand is in its infancy and we still haven’t been able to get more energy out than we put in. I am all for continuing investing in and developing the technology, as we will need energy for as long as our species is around. However, I am not counting on fusion to contribute to any meaningful decarbonization within the next decades.

One of the craziest things you’ve mentioned is that a natural nuclear reactor existed hundreds of thousands of years before humans did, can you tell us about it?

Two billion years ago Gabon, a country in Africa, was home to the only known natural nuclear reactor in the world: Oklo! Scientists discovered this after being puzzled by the fact that the Uranium from that region had lower concentrations of U-235, the fissile isotope in Uranium. After some investigation they discovered that billions of years ago the uranium caves in the region had just the right conditions which allowed chain reactions to take place.

When it rained, rain water would pool around the uranium in the cave and serve as a moderator. Oklo sustained chain reactions for hundreds of thousands of years. I love this fun fact because nuclear power seems like an alien technology, but in reality it appeared in nature, long before humans were around. It also tells us what happens to nuclear waste and proves that it can be safely disposed of when placed deep in stable rocks.The biggest argument against nuclear power is the waste it produces, often claimed that the waste stays radioactive for thousands of years.

Let’s talk Terrapower, the nuclear fission start up by Bill Gates, they’re aiming to power their reactors with nuclear waste, how is that possible, and is this the next stage of nuclear advancement?

Breeder reactors can literally run off of nuclear waste by recycling it and that’s how most historical national nuclear energy programs envision their progression. If we were to build a lot of these reactors, there’s enough energy in the current spent fuel to power the whole USA for around 100 years. Terrapower however, isn’t working on a traditional breeder reactor. They are working on a related technology called Natrium, a high temperature reactor that’s plugged into a thermal energy storage system, which allows it to integrate really well with variable renewables like wind and solar.

More traditional nuclear reactors can turn their output up or down to accommodate renewables as well, but it’s not economically attractive. By having the plant connected to a thermal energy storage system the Natrium would bypass these issues. The plant would charge the storage system when solar and wind are producing a lot of electricity and have both the reactor and storage provide electricity at night or when the wind is not blowing.The other cool thing about Terrapower is that they’re building their first reactor near a retiring coal plant in Wyoming. They can utilize the existing transmission lines and some of the infrastructure and retrain the workforce, who would otherwise simply lose their jobs when the coal plant retired.

Thorium seems to be the word on everyone's lips for nuclear, it’s more abundant on Earth, it doesn’t need enrichment like Uranium, how does Thorium fit into the future of nuclear?

There is a saying in the nuclear community that people come for the Thorium and stay for the LWR [light water reactor, a more traditional design of nuclear reactors]. I was one of those!

Thorium sounds like a miracle and the truth, as always, is that it’s a little more complicated than that. It is more abundant than uranium on the Earth’s crust and we can absolutely use it as fuel. In fact, Thorium was used in one of the reactors at the late Indian Point Power Plant in NY, however it was more expensive than using Uranium so they switched it to the latter. Thorium doesn’t need enrichment, but that is because it’s not fissile so you still have to mix it with U-235 in order to start a chain reaction. Therefore it does require enrichment.

There are some claims that Thorium cannot be used to make bombs, but that is a half truth, it only requires one extra step. If a bad agent is very committed to creating a bomb with Thorium, they can. I think Thorium can be used in parallel with Uranium, but I don’t see it becoming the only fuel for nuclear power plants.Who are you excited about that is creating the future for nuclear, in essence who is on your radar?In countries like the United States, building traditional reactors has proven difficult recently. These are massive projects that end up being delayed and over budget, so several startups are trying to develop smaller and modular reactors that can be standardized.

Companies like Oklo, who are building modular micro-reactors [1.5 MW] that can be used to replace diesel generators in remote areas. Terrapower, who are designing a high temperature reactor plugged into a thermal energy storage, which pairs really well with renewables. Terrestrial Energy are building a molten salt modular reactor that also pairs well with renewables. Terrapower and Terrestrial Energy reactors also create high grade heat, which can be used for industrial applications. These are just a few of the many new nuclear energy companies that are trying to build advanced reactors that are smaller, standardized and hopefully cheaper.

Countries like Korea, Russia and China have had more success building traditional reactors on time and on budget. They are now building those all over the world. For example, Korean KEPCO has built one 1,400 MW unit in the United Arab Emirates, with three more being built. 

Read the full article in ISSUE 08 of CYBR MAGAZINE