Technology
Deep Fission combines three technologies into one solution called the Gravity Nuclear Reactor, significantly reducing the cost and complexity of surface infrastructure.
Traditional Reactor,
Boring Placement
Unlike other small modular reactor (SMR) designs, Deep Fission combines standard oil & gas borehole drilling, geothermal technology, and the most common reactor type, a pressurized water reactor (PWR), to create a small modular reactor that can be placed in an optimized borehole, one mile underground.
Each Deep Fission Gravity Reactor generates 15 MWe. With a small footprint and dense power output, ten reactors produce 150 MWe, while 100 reactors on one site can deliver 1.5 GWe, requiring a fraction of the land needed for traditional surface nuclear.
PWR Design
The Deep Fission Gravity Nuclear Reactor uses the traditional pressurized water reactor design for its fuel assemblies and power control methods. Gravity reactors operate at the same ~315°C core temperature, and hydrostatic pressure from one-mile-deep column of water provides the same 160 atm of reliable pressure, safely and naturally.
The heat produced is transferred to a steam generator at depth to boil water. This novel deployment approach applies proven geothermal components and processes for energy transfer. Non-radioactive steam rises rapidly to the surface, where a standard steam turbine converts the energy to electricity.
PWR uses readily available low-enriched uranium (LEU) fuel.
Benefits of Gravity Reactor Technology

Development Timeline
Deep Fission is building its first Gravity Nuclear Reactor for fast commercial viability.
2025: One of 10 companies selected for DOE Pilot Program, groundbreaking at first commercial site
2026: DOE Nuclear Reactor Pilot authorization
2027-2028: First 150 MWe commercial plant operational

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