A striking new idea in the race for next-generation nuclear energy is taking shape beneath the ground in Parsons, Kansas. Deep Fission, founded in 2023 by father-and-daughter team Rich and Liz Muller, is developing a concept that places a small pressurized-water nuclear reactor deep inside a borehole rather than housing it in a conventional surface nuclear plant. The company’s current plan is to demonstrate its technology through the U.S. Department of Energy’s Reactor Pilot Program, with a commercial pilot targeted for 2027. The project represents a significant departure from traditional nuclear construction and comes as electricity demand from data centers, industry and artificial intelligence continues to increase.
The basic concept sounds almost futuristic: put the reactor roughly a mile underground and use the surrounding geology as part of the safety system. Instead of constructing a massive above-ground containment structure, Deep Fission’s Gravity Reactor is designed to take advantage of the rock and water surrounding the underground installation. The company says its approach is intended to provide passive shielding and containment while reducing the amount of expensive infrastructure required at the surface. The idea grew from the Mullers’ earlier work on Deep Isolation, which focused on using deep boreholes for nuclear-waste disposal. Deep Fission applies related borehole technology to a very different objective—generating electricity.
