How deep can wells be drilled to reach geothermal resources?

To reach geothermal resources, wells are drilled to varying depths depending on the location and the nature of the reservoir. In some instances, these wells can reach depths of up to 9,100 meters (approximately 30,000 feet).1

The ability to access these resources is a critical factor in the viability of geothermal power. While high-temperature heat is often found relatively close to the surface in regions characterized by recent volcanism or tectonic plate boundaries, engineers are also developing enhanced geothermal systems (EGS) to access deeper, less accessible hot rock in non-volcanic areas.123

Because temperatures within the Earth increase at a rate of approximately 30 °C per kilometer (roughly 90 °F per mile) in the first 10 kilometers below the surface, drilling deeper allows for the potential extraction of greater thermal energy. However, the economic feasibility of these projects remains a primary consideration, as the cost of drilling and exploration increases with depth and complexity.413