Rystad Energy, 10-10-2020
- Per Rystad Energy analysis, global geothermal power production capacity will rise from 16 gigawatts at the end of 2020 to 24 GW in 2025.
- This growth will unlock total investments of $25 billion over the next five years.
- From 2010 to 2020, total investment reached $40 billion.
- The number of wells drilled globally will increase from 223 in 2019 to 380 in 2025.
- Contrary to wind and solar, the surface footprint of a geothermal plant has the advantage of being much lower in terms of square kilometers per MW of produced electricity.
- A geothermal power plant usually consists of two to six wells, with one well producing and the additional wells receiving re-injected separated water.
- Each well, on average, had an installed capacity of 5.3 MW, but well capacity appears to be trending upwards as wells are drilled deeper and production is optimized.
- Historically, overall project cost is comprised of around 35% to 40% well CAPEX and 60% to 65% surface facilities and infrastructure, highly dependent on depth.
- There are three technology types currently in use;
- binary cycle power plants, which are used for colder water reservoirs by implementing a heat exchanger,
- flash steam plants which take high-pressure hot water and transport it to lower pressure surface tanks where it is converted to steam to power a turbine,
- dry steam power plants which take steam directly from the geothermal reservoir to turn the turbines.
- Geothermal projects have generally been developed in countries with high enthalpy resources, which are associated with active volcanic areas such as in Iceland, Italy, and Turkey. In Iceland, conventional geothermal wells are drilled down to a depth of up to 2,500 meters to reach high-temperature reservoirs, measuring up to 450 °C.