Investing in a world powered by nuclear fission

It’s not just the current political climate leading to a renewed interest in nuclear power. The story of nuclear fission is one of decreasing physical size, increasing safety, and increasing efficiency.

Thorium fuel: Like HALEU for fast reactors, thorium fuel is also more efficient, as the thorium can be fully consumed and then recycled, without needing continuous replenishment of fuel. Thorium today is only beginning to be incorporated into nuclear reactors in countries like India, where thorium supply is abundant.

Pebble fuel: Typically used for HTGRs, fuel pebbles are meltdown-resistant small, solid pellets that encase uranium fuel (typically HALEU). The pellets retain fission products under all reactor conditions and are structurally more resistant to neutron irradiation, corrosion, and high temperatures than are traditional reactor fuels. TRISO (TRi-struc... See more

High-assay low-enriched uranium (HALEU): HALEU is a uranium fuel that contains ~20% U-235. Based on the demand by SMRs and microreactors for HALEU, we’ll need capabilities to develop dozens of metric tons of HALEU uranium in the next decade.

There is also an innovation on the front of new fuels:

High-temperature gas reactors (HTGRs): In HTGRs, gasses (typically helium) act as the coolant that is fed directly into the turbine to produce energy. Helium is an inert gas, so it generally won’t chemically react with any material, and exposing helium to neutron radiation won’t make it radioactive. Helium can therefore be heated to higher temperat... See more

Sodium fast reactors (SFR): In SFRs, liquid sodium acts as the coolant instead of water. Liquid sodium, compared to water, can handle higher temperatures at lower pressures, which improves the efficiency and safety of the reactor.

Molten Salt Reactors (MSRs): In MSRs, molten salt (e.g., fluoride, chloride) contains the nuclear fuel (i.e., uranium). The molten salt also acts as the coolant, and graphite rods act as the moderator. Replacing water as the coolant removes the possibility of steam explosions and the generation of flammable hydrogen gas. The nuclear reactions in MS... See more

Within the broad umbrella of SMRs and microreactors, though, there are a number of additional innovations.