What is geothermal energy? Answer: It is a type of energy.The temperature of the earth's core waves outward. This thermal power is known as geothermal energy. Many countries of the world produce electricity from this thermal power. Iceland meets upto 30% of the total energy requirement from geothermal energy. The U.S.A produces highest amount of electricity in the world from geothermal energy. Electricity production from geothermal energy reduces the use of fossil fuel (coal, petroleum).