Geothermal energy utilizes the accessible thermal energy from the Earth’s interior. Heat is extracted from geothermal reservoirs using wells or other means.
Reservoirs that are naturally sufficiently hot and permeable are called hydrothermal reservoirs, whereas reservoirs that are sufficiently hot but that are improved with hydraulic stimulation are called enhanced geothermal systems.
Once at the surface, fluids of various temperatures can be used to generate electricity. The technology for electricity generation from hydrothermal reservoirs is mature and reliable, and has been operating for more than 100 years.
How Geothermal Energy Work?
Geothermal power plants come in three different designs; dry steam, flash and binary:
The oldest type is dry steam, which takes steam directly from fractures in the ground to drive a turbine.
Flash plants pull high pressure hot water from underground and mix it with cooler low pressure water. This, in turn, creates steam that is used to drive a turbine.
Binary plants use hot water passed through a secondary fluid that has a lower boiling point than water. The secondary fluid is turned into vapour which drives a turbine. Most future geothermal power plants are expected to be binary plants.
Advantage and Disadvantage of using Geothermal Energy
Advantages of Geothermal Energy
1. Geothermal Energy Sourcing Is Good for the Environment
2. Geothermal Is a Reliable Source of Renewable Energy
3. High Efficiency of Geothermal Systems
4. Little to No Geothermal System Maintenance
Disadvantages of Geothermal Energy
1. Environmental Concerns about Greenhouse Emissions
2. Possibility of Depletion of Geothermal Sources
3. High Investment Costs for Geothermal System
4. Land Requirements for Geothermal System to Be Installed
The largest users of Geothermal Energy
The global geothermal power generation capacity stood at 16,355 MW at the year-end 2023. Growth is picking up with further growth expected for 2024.
