During the search for new sources of renewable, clean power, geothermal energy is usually forgotten, even though it is one of the most useful and renewable energy sources on the planet. The exploitation of geothermal energy resources is increasing around the world as people search for solutions to climate change and the use of fossil fuels. But what is geothermal energy? And in what scenarios can it be used in the future?
This article will provide comprehensive information about geothermal energy, explain how geothermal power plants work, discuss the pros and cons of geothermal energy, discuss geothermal power plants in India, and compare the advantages and disadvantages of geothermal energy with the advantages and disadvantages of thermal power plant systems.
Definition of Geothermal Energy
Let’s get into what geothermal energy is and go through its definition. So, geothermal energy refers to the thermal energy within the Earth. In simplest words, geothermal means earth and thermal means heat. Therefore, the term geothermal refers to heat from the earth. This heat is found a few miles beneath the Earth’s crust, in the form of hot water and rocks, along with the core of the earth.
The geothermal energy’s uses range from producing electricity, heating, drilling, greenhouse farming, and aquaculture to fish farming — all of which harness the Earth’s abundant geothermal energy.
It is here important to note that thermal energy that is stored within Earth can be harnessed, bringing benefits for electrical production, direct heating, industrial applications, aquaculture, and even farming.
How Can We Extract the Heat Energy from Within Earth?
Unlike other sources of energy such as solar, wind, or hydroelectricity, geothermal energy doesn’t come from the sun. It is the internal heat from the Earth itself that can be accessed by drilling wells on the surface. Otherwise, hot steam owned in geothermal reservoirs can be captured and switched into electricity using power plants known as geothermal power plants. Geothermal power plants procure great amounts of steam or water found at the base of the Earth. This steam or water is used for moving turbines, enabling the production of electricity.
There are three major types of geothermal power plants:
- Dry Steam Power Plants—This oldest method employs thermal energy from the steam itself, which directly empowers the turbine.
- Flash Steam Power Plants — If the water is located at a greater depth, hot water will exist there under a great amount of pressure. Once water is brought to the surface, its pressure drops, which makes it possible for steam to be produced to move turbines.
- Binary Cycle Power Plants—The vaporized geothermal water replaces a different kind of liquid, which will then vaporize, spin the turbine, and help move electricity.
Geothermal Power Plants in India
There are an impressive number of geothermal energy power plants in India due to its diverse geological wonders. Several projects are still in the planning phase, but a few of the sites are set for development in the future.
The Most Important Geothermal Hotspot in India:
- Puga Valley (Ladakh): the most promising site for geothermal power.
- Tattapani (Chhattisgarh): Known for its strong geothermal activity.
- Manikaran (Himachal Pradesh): Another important geothermal site hosting hot springs.
- Unai (Maharashtra) and Bakreshwar (West Bengal): Two sites possessing geothermal features while undergoing research.
Renewable Energy Development agencies such as the Ministry of New and Renewable Energy (MNRE) are supporting the research and pilot projects so that geothermal power plants in India can be made more accessible.
The Advantages and Disadvantages of Geothermal Energy
A form of renewable energy, geothermal energy has its advantages as well as concerns.
Advantages of Geothermal Energy
- Low Emissions: The pros of harnessing energy from the Earth’s crust are that it’s not highly damaging to the environment, releasing quite lesser emissions than fossil fuels.
- Renewable & Sustainable: Geothermal energy reserves are available in almost unlimited quantities and are considered the safest source of energy for the future.
- Small Land Footprint: Geothermal power plants take up less land than other energy plants.
- Base Load Power Supply: Unlike solar or wind, geothermal energy has the ability to supply power consistently irrespective of the weather conditions.
- Cost-Effective in the Long Run: Under geothermal energy, the operational costs are low after the initial investment.
- Direct Use Applications: Geothermal energy can be used aside from electricity in heating, spas, agriculture, and many other industries.
Disadvantages of Geothermal Energy
- High Initial Costs: The very first geothermal energy implementations such as drilling, and building the geothermal power plant can be costly.
- Location Specific: The most efficient use of geothermal energy needs certain geological conditions to be present like active volcanoes.
- Risk of Earthquakes: The act of deep drilling can lead to seismic activity.
- Resource Depletion: If not properly managed, the state of efficiency of geothermal energy can lower over time, leading to waste.
- Environmental Concerns: The process of extracting geothermal energy might on rare occasions lead to releasing harmful gases such as carbon dioxide or methane.
Advantages and Disadvantages of Thermal Power Plant
While comparing energies like geothermal, it is necessary to understand the advantages and disadvantages of thermal power plant systems that use fossil fuels including coal, gas or oil.
Advantages of Thermal Power Plant
- Established Technology: With the use of fossil fuels, power is generated through geothermal technologies; thus, it means the thermal power plants have been in use for 100 years or more.
- Reliable and Flexible: Power generation can be continuous and easily adjusted to meet demand.
- Infrastructure Availability: There is already an existing grid and transportation infrastructure.
Disadvantages of Thermal Power Plant
- Pollution: Significant emissions of greenhouse gases result in severe climate change.
- Non-renewable: It depends on dwindling fossil fuel reserves.
- Water Intensive: Requires a significant amount of water for cooling purposes.
- Health Risks: Public health is harmed as a result of pollution caused by the emission of sulfur dioxide, nitrogen oxides, and particulate matter.
Geothermal Energy vs. Thermal Power
When comparing geothermal energy with conventional thermal power plants, it has cam to the light that geothermal energy is much more eco-friendly and sustainable. While thermal power still dominates global energy due to existing infrastructure and capacity, it certainly possesses a green alternative in the form of geothermal energy, which can be further developed with technological innovation and investment.
Future of Geothermal Energy
Geothermal energy is becoming increasingly relevant due to the global carbon neutrality and green energy drive. Countries like Iceland and the Philippines, along with the United States, are already utilizing this form of energy on a large scale, leading the way.
Through the support of research and policies, India can utilize its geothermal potential while reducing dependency on fossil fuels. The addition of geothermal power plants would also aid in the electrification of the remote areas of the country, improve energy security, and foster sustainable economic progress.
Additionally, technological advancements such as enhanced geothermal systems (EGS) can further extend the boundaries of this energy type by creating reservoirs in areas that do not possess natural hydrothermal resources.
Conclusion
Currently, untapped geothermal energy is one of the cleanest and most powerful sources of energy available. Its range of applications includes the generation of electricity through a geothermal power plant, heating homes or industries directly, and many others.
As with any other energy option, there are some advantages and disadvantages of geothermal energy, where the benefits far outweigh the drawbacks. This is especially true when considering the shift towards renewable energy sources making the case for more investment, research, and policy initiatives with respect to geothermal power plants in India.
Ultimately, a thermal power plant system’s strongest contender is clearly in the form of geothermal energy, serving to not only shift the paradigm of energy sources in the world but also do so in a much cleaner and more efficient manner.
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