Geothermal energy

Introduction:

Geothermal energy is a renewable energy source produced from the heat inside Earth. In this lesson, we will learn about how geothermal energy is produced and will discuss its merits and limitations.

Explanation:

Geothermal Energy:

Geothermal energy is the heat of the Earth and is the naturally occurring thermal energy found within rock formations and the fluids held within those formations.

Geothermal energy is one of those few sources of energy that do not come directly or indirectly from solar energy.

Geothermal Power Plant

The underground hot water in contact with hot spots changes into steam. As the steam is trapped between the rocks, it gets compressed to high pressure. In some places, hot water and steam gush out from the Earth’s surface after making their way through large cracks between the rocks and forming natural geysers. Geothermal energy carried by natural geysers is utilized for generating electricity.

Merits of Geothermal Energy:

1. Geothermal energy is the most versatile and least polluting renewable source of energy.
2. It can be harnessed for 24 hours throughout the year.
3. Geothermal energy is relatively inexpensive.
4. As compared to solar energy and wind energy, the power generation level of geothermal energy is higher.
5. Geothermal energy can be used for power generation as well as direct heating. In the USA, water is pumped from underground hot water deposits and is used to heat houses.

Limitations of Geothermal Energy:

1. Geothermal hot spots are scattered and usually are some distance away from the areas that need energy.
2. Overall power production has a lower efficiency (about 15%) as compared to that of fossil fuels (35% to 40%).
3. Noise pollution is caused by drilling operations at geothermal sites.

Questions and Answers

Question 1: What is geothermal energy, and how does it work?

Answer: Geothermal energy is energy produced from the heat inside Earth; it can be used to heat buildings and generate electricity.

Question 2: How can the use of geothermal energy help address climate change?

Answer: Increased use of geothermal energy could help reduce greenhouse gas emissions.

Summary

• Geothermal energy is the heat of the earth and is the naturally occurring thermal energy found within rock formations and the fluids held within those formations.
• Geothermal heat pumps are a system used in commercial and residential buildings that provides heat in winter by transferring heat from the earth through ductwork, and into the indoor air delivery system of a building. In the summer, the process is reversed for cooling.
• A geothermal power plant is a facility that generates electrical energy by using hot water from a geothermal reservoir to power electrical generators.
• A geothermal reservoir is a natural collection of hot underground water usually trapped under a rock layer under the earth’s surface. Temperatures can be as high as 700 degrees and the water can form hot springs and geysers on the surface of the earth.