Geothermal Energy PDF

Learning Objectives: Explain how heat from inside the Earth (geothermal) and from flowing water (hydroelectric) is tapped as a source of energy for human use (S11ES-Ie-f-11).  Table of contents 1 2 3 What is How...

Learning Objectives: Explain how heat from inside the Earth (geothermal) and from flowing water (hydroelectric) is tapped as a source of energy for human use (S11ES-Ie-f-11).  Table of contents 1 2 3 What is How How to harness Geothermal Geothermal Geothermal Energy? Energy Works? Energy? What is renewable energy?  Renewable energy is often referred to as clean energy. It is energy resulting from natural resources that replenish themselves over a period without exhausting the Earth's resources. Nonrenewable resource is a natural susbtance that is not replenished with the speed at which is consumed What are the TWO examples of renewable energy? A. Coal and Oil B. Hydrothermal Energy and Geothermal Energy C. Natural Gas and Geothermal Energy It literally means heat from the Earth? A. Hydrothermal Energy B. Geothermal Energy C. Wind Energy B. Geothermal Energy  Almost 45% is generated by geothermal energy The heat from this energy comes from the decay of radioactive elements and the residual heat produced when the planet formed. A. Wind Energy B. Hydrothermal Energy C. Geothermal Energy C. Geothermal Energy People can harness geothermal energy. TRUE FALSE TRUE It taps into heat close to the Earth’s surface to heat water or provide heat for buildings A. Geothermal power plants B. Geothermal heat pumps C. Direct Geothermal Energy B. Geothermal Heat Pumps HOW GEOTHERMAL HEAT PUMP WORKS? It uses heat from deep inside the Earth and generate steam to make electricity. A. Geothermal power plants B. Geothermal heat pumps C. Direct Geothermal Energy A. Geothermal Power Plants HOW GEOTHERMAL POWER PLANT WORKS?  Geothermal Power Plants 1. At a geothermal power plant, wells are drilled 1 or 2 miles deep into the Earth to pump steam or hot water to the surface. 2. Hot water is pumped from deep underground through a well under high pressure. 3. When the water reaches the surface, the pressure is dropped, which causes the water to turn into steam. 4. The steam spins a turbine, which is connected to a generator that produces electricity. 5. The steam cools off in a cooling tower and condenses back to water. 6. The cooled water is pumped back into the Earth to begin the process again.  Types of Geothermal Power Plants  Dry Steam Plants Hot steam is piped directly from geothermal reservoirs into generators in the power plant. The steam spins turbines, which generate electricity. One of 22 dry steam plants at The Geysers in California  Flash Steam Plants Water that's between 148 and 371 degrees Celsius is brought up through a well. Some of the water turns to steam, which drives the turbines. When the steam cools it condenses back into water and is returned to the ground.  Warakei Geothermal Power Plant, New Zealand's oldest and largest geothermal plant (image from thinkgeoenergy)  Binary Cycle Plants Moderately hot geothermal water is passed through a heat exchanger, where its heat is transferred to a liquid (such as isobutene) that boils at a lower temperature than water. When that fluid is heated it turns to steam, which spins the turbines.  In areas where hot springs or geothermal reservoirs are near Earth’s surface, hot water can pipe in directly to heat homes or office buildings. A. Geothermal power plants B. Geothermal heat pumps C. Direct Geothermal Energy C. Direct Geothermal Energy