| Title | Geothermal – not just for Earth |
|---|---|
| Authors | Ken Wisian |
| Year | 2026 |
| Conference | World Geothermal Congress |
| Keywords | |
| Abstract | As humanity expands into the solar system, abundant power will be needed. One possibility with potential for powering installations on planetary bodies, particularly the outer solar system, is geothermal generation. All that is needed to produce geothermal energy is an exploitable temperature differential between a source and a sink. This technology has been producing electricity on Earth for more than 100 years from temperature differences of about 125°C or greater. This generation is typically done via a fluid phase change driving a turbine/generator. Many moons and dwarf planets are water/ice worlds with an outer crust of ices overlying a planet-wide ocean. On these bodies, such as the moons of Jupiter and Saturn, there is an exploitable 150-250°C difference between the temperature of the ocean and the ambient surface temperature. Various engineering approaches could generate usable power from this setting. The rim of polar region craters on the Moon offer a different near-term potential geothermal-ish development option using ThermoElectric Generators (TEG) and the ~150°C difference between the sunlit and permanently shadowed sides. TEG have low efficiencies, but this might be offset by the lack of moving parts (greater reliability) and ability to deploy may TEGs cheaply and quickly. This could be a resilient and reliable adjunct to solar cells or other power sources. While significant engineering issues need to be solved in producing this style of energy, the potential, particularly on icy bodies is on the order of Megawatts of power generation per well. |