Geothermal Energy

These notes are based on the chapter Sources of Energy of class 10 NCERT book and CBSE syllabus.

Thermal energy extracted from the earth's surface is called geothermal energy. Electricity produced by harnessing geothermal energy is called geothermal power.

The molten rocks from the inside of the earth are pushed in certain regions of the earth. Such regions are called the hot spots of the earth. When groundwater comes in contact with such hot spots, lot of steam is generated. This steam can be harnessed to produce energy. Many power plants in New Zealand and USA operate on geothermal energy.

Geothermal energy has been used by man sine prehistoric times. Many public baths during the ancient times used geothermal energy for heating water.

Advantages of Geothermal Energy

• It is highly cost effective.
• This is an inexhaustible source of energy.
• Power production from geothermal energy does not depend on weather and hence can be a continuous source of energy.

Disadvantages of Geothermal Energy

• Geothermal energy can only be used at select places where fissures are present on the earth's surface.
• Source of geothermal energy produces many harmful gases such as oxides of sulphur.

Nuclear Energy

Nuclear fission is the process during which a nucleus of an atom breaks to form two nuclei. The process generates a huge amount of energy. This phenomenon is utilized in nuclear power plants.

• In a nuclear power plant, the nuclear reactor is the source of heat.
• The heat from reactor is utilized to produce steam.
• The steam is utilized to turn the turbine to generate electricity.
• The steam then goes to the cooling tower so that liquid can be reused.

Nuclear power is safest for the environment but the risk of damage due to accidental leaks of radiation is pretty high. Further, storage of nuclear waste is a big problem because of potential risk of radiation involved.

Nonetheless, many countries are using nuclear power in a big way. India too has built many nuclear power plants. As of November 2020, there are 22 nuclear reactors and 8 nuclear power plants in India.

Recent accidents in the nuclear power plants in Chernobyl and Japan have forced the policymakers to rethink about the nuclear power.