Deep Fission unveils underground reactor concept

Thursday, 29 August 2024

Deep Fission aims to locate 15 MWe pressurised water reactors (PWRs) about one mile (1.6 km) underground in a 30-inch borehole. The reactor operates at the same pressure (160 atmospheres) as a standard PWR, and at the same core temperatures (about 315°C). As with a standard PWR, the heat is transferred to a steam generator at depth to boil water, and the non-radioactive steam rises rapidly to the surface where a standard steam turbine converts the energy to its electricity.

The company says its concept eliminates the need for large pressure vessels and containment structures, significantly reducing costs while enhancing safety, sustainability, and operational efficiency. It says this can be done using conventional low-enriched uranium fuel and an existing supply chain, "sidestepping a significant source of delay and concern for other advanced reactor designs".

"I am thrilled to introduce Deep Fission and present our groundbreaking approach to affordable nuclear power," said Deep Fission co-founder and CEO Elizabeth Muller. "Climate change has accelerated the need for clean energy, and nuclear must be cheaper in order to compete with coal and natural gas.

"We’ve innovated beyond other reactor designs and engaged early and often with the Nuclear Regulatory Commission (NRC) to make atomic energy a viable option to power AI, industrial applications, as well as remote communities. We cannot wait to share our findings with the world and do our part to help with the clean energy transition."

The company said it has already met several important milestones, including completing a conceptual design, submitting a regulatory engagement plan, a conceptual design white paper, and a conceptual design review meeting with the NRC.

The infusion of capital - led by technology and bio-sciences investment firm 8VC - will accelerate efforts in hiring, regulatory approval, and the commercialisation of the company's reactor technology, Deep Fission said.

"Cheap energy fuels our prosperity and all of our technology," said 8VC Managing Partner Joe Lonsdale. "With global demand escalating, we need more options. We invested in Deep Fission because they are engineering a way for nuclear power to be exceptionally safe, cost-effective, and reliable - and far enough underground that hopefully neither war nor regulators can turn it off!"

Deep Fission was founded in 2023 by father-daughter team Elizabeth and Richard Muller, who also co-founded Deep Isolation in 2016 to develop the concept of placing canisters of radioactive waste hundreds of metres underground via a borehole.