Geothermal power harnesses deep Earth heat as electricity by injecting underground hot water or steam, forcing it to drive turbines, and producing electricity. Cool water is thereafter pumped underground to maintain the system.
What Happens Within a Geothermal Power Plant?
1. Production Well
Drills penetrate deeply into hot water or steam reservoirs, which tend to rise under pressure.
2. Steam powers a turbine
- Dry steam plants provide natural steam directly to turbines via piping.
- Flash steam power plants are fed high-pressure hot water; water flashes into steam to drive turbines when pressure is lost.
- Moderate-temperature water is employed in binary cycle power plants to vaporize low-boiling-point secondary fluid for heating, generating vapor to drive turbines.
3. Generator Converts Motion to Electricity
The turbine’s spin powers an electric generator, converting energy into power.
4. Cooling & Reinjection
After passing through the turbine, steam or vapor is condensed in a condenser and reinjected underground through injection wells, with the reservoir pressure maintained constant.
What are the main plant types?
There are three broad categories of geothermal power plants:
- Dry Steam Plants: These employ steam directly from the earth to drive a turbine and produce electricity. It is the most rudimentary and oldest form.
- Flash Steam Plants: These are the most common nowadays. They produce underground hot water, which is converted to steam when the pressure is released. This steam is employed to power the turbine.
- Binary Cycle Plants: These use hot water to heat another liquid having a lower boiling point. That second liquid evaporates and spins the turbine. These plants work well with lower-temperature water.
FAQs
The formation of the planet, along with radioactive decay and residual heat from the Earth’s core, generates heat beneath the surface. In geothermal “hot spots,” this heat warms groundwater to high temperatures, typically exceeding 150°C, which leads to the creation of steam or hot water reservoirs. These reservoirs are usually located near tectonic zones or volcanoes.
The closed-loop system, where used water is recycled back into the reservoir, keeps the water flowing and lessens depletion. This enables geothermal power plants to operate around the clock, providing baseload power.
References
The information in this article is based on insights from respected organizations in the energy field. We have reviewed content from the following sources to ensure accuracy and relevance:
Posted by Abu Talha
With a background in science at the A-level, Abu Talha has studied subjects including physics, chemistry, mathematics, and biology. Along with his more than 1.5 years of experience in digital marketing, he is passionate about writing about electric vehicles, sustainable energy, and how emerging technologies are influencing the future.
