Brine and steam temperatures in geothermal systems range from 212 ° F to 698 ° F and often contain silica, lime, sulphur, and other minerals. Advances in geothermal technology now allow electricity generation even from brine at 212 ° F or lower. Valves are critical in this process. They must minimise pressure loss while withstanding these impurities. Steam up to 698 ° F- and in future SCGT and SHR systems, even hotter- adds further challenges for valves and the overall system. Poor valve selection or maintenance can cause energy loss, inefficiency, or serious damage, especially to separators and turbine blades. Geothermal plant valves also face harsh conditions, including high pressure, flashing, and silica scaling, while still ensuring safe, efficient flow control. Pressure and temperature fluctuations demand high valve performance. A major issue is silica scaling; deposits inside valves lead to leakage, which accelerates π www. valve-world. net Valve World October 2026
With reliable, high-quality valves, geothermal power plants can produce renewable energy efficiently and safely at a low cost and low environmental impact.
The critical role of valves in geothermal energy
Geothermal energy is continuously produced inside the earth. In addition to thermal energy, in some areas the geothermal fluid may contain lithium, which is vital for batteries used to power the energy transition. We just need to harness that energy, and the lithium, in a sustainable way. Reliable, highperformance valves play a significant role in producing renewable energy from geothermal sources.
By Andreas Pischke- Global Industry Manager- Valmet Flow
Control Business Line
Industrial processes for cleaner energy
Geothermal power plants harness the Earth’ s internal heat by extracting geothermal fluids, typically in the form of hot brine or steam, which are then used to drive turbines connected to generators, producing electricity. If the lithium content in the brine is big enough, one of the Direct Lithium Extraction( DLE) methods can be applied to capture this additional benefit from geothermal recourses. Hydrothermal geothermal power plants where the fluid is extracted directly from the underground are most common. These power plants can work as one of three types; flash steam, dry steam or binary cycle. Binary cycle power plants operate using a secondary working fluid with a low boiling point – commonly a hydrocarbon such as Pentane. This fluid is heated by the geothermal brine, causing it to vaporise and drive an Organic Rankine Cycle( ORC) turbine to generate electricity. There are also so-called Enhanced Geothermal Systems( EGS) and Advanced Geothermal Systems( AGS) applied. Also, the Superhot Rock System( SHR) and the Supercritical Geothermal Technology( SCGT) are still notably in the R & D stage and yet to be commercially applied.
Serving a global demand for geothermal
Currently, Indonesia has the highest annual geothermal production while the U. S. still has the highest amount of installed capacity, even if geothermal only accounts for a fraction of the energy used nationally. Countries such as Kenya, Iceland, New Zealand, and El Salvador are already heavily dependent on geothermal for a large part of their energy.
As the global demand for lithium, an essential component in batteries, continues to grow, countries such as the US, Germany and Chile are exploring synergies with geothermal where the brines often contain dissolved lithium. Pilot projects for the extraction of lithium from brine are already in motion. By using advanced direct lithium extraction( DLE) technologies, it is already possible to recover lithium without significantly disrupting the geothermal process.
Efficiency performance in harsh conditions
Brine and steam temperatures in geothermal systems range from 212 ° F to 698 ° F and often contain silica, lime, sulphur, and other minerals. Advances in geothermal technology now allow electricity generation even from brine at 212 ° F or lower. Valves are critical in this process. They must minimise pressure loss while withstanding these impurities. Steam up to 698 ° F- and in future SCGT and SHR systems, even hotter- adds further challenges for valves and the overall system. Poor valve selection or maintenance can cause energy loss, inefficiency, or serious damage, especially to separators and turbine blades. Geothermal plant valves also face harsh conditions, including high pressure, flashing, and silica scaling, while still ensuring safe, efficient flow control. Pressure and temperature fluctuations demand high valve performance. A major issue is silica scaling; deposits inside valves lead to leakage, which accelerates π www. valve-world. net Valve World October 2026
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