A lava fountain is an example of the amount of heat stored in the Earth. Geysers, lava mountains and hot springs are all natural examples of geothermal energy. In addition, geothermal energy is now a lot more common in homes and businesses, using geothermal heat pumps to cool and heat buildings.
Geothermal energy is derived from the Earth's natural heat, which increases with depth. It has two main applications: heat production (via heat pumps or by direct heat exchange), power production (via steam turbines).
Direct use of geothermal resources is the use of underground hot water to heat buildings, grow plants in greenhouses, dehydrate onions and garlic, heat water for fish farming, pasteurize milk, and for many other applications. Some cities pipe the hot water under roads and sidewalks to melt snow.
Geothermal power plants use steam to produce electricity. The steam comes from reservoirs of hot water found a few miles or more below the earth's surface. The steam rotates a turbine that activates a generator, which produces electricity.
Geothermal Energy Pros and Cons
| Pros | Cons |
|---|
| No cost fluctuations determined by gas and oil prices. | Fewer installers than standard HVAC and thus less competition. |
| 30%-60% savings on heating and 25%-50% savings on cooling. | Large scale geothermal power plants are dangerous to the Earth's surface and location-centric. |
Wind Power Plant Presentation (Seminar PPT) ? The wind is a by-product of solar energy. Approximately 2% of the sun's energy reaching the earth is converted into wind energy. ? The surface of the earth heats and cools unevenly, creating atmospheric pressure zones that make air flow from high- to low- pressure areas.
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. When the water reaches the surface, the pressure is dropped, which causes the water to turn into steam. The steam spins a turbine, which is connected to a generator that produces electricity.
Geothermal energy (from the Greek roots geo, meaning earth, and from thermos, meaning heat) is energy made by heat inside the Earth's crust. Although the Sun does heat the surface of the Earth, the heat from inside the Earth is not caused by the Sun.
Since 2015 the three countries with the greatest capacity for geothermal energy use have included the United States, Indonesia, and the Philippines. Turkey and Kenya have been steadily building geothermal energy capacity as well.
The largest group of geothermal power plants in the world is located at The Geysers, a geothermal field in California, United States. As of 2004, five countries (El Salvador, Kenya, the Philippines, Iceland, and Costa Rica) generate more than 15% of their electricity from geothermal sources.
U.S. geothermal power plants are located in the West
Most of the geothermal power plants in the United States are in western states and Hawaii, where geothermal energy resources are close to the earth's surface. California generates the most electricity from geothermal energy.There are many advantages of geothermal energy. It can be extracted without burning a fossil fuel such as coal, gas, or oil. Geothermal fields produce only about one-sixth of the carbon dioxide that a relatively clean natural-gas-fueled power plant produces. Binary plants release essentially no emissions.
Most of the geothermal power plants in the United States are in western states and Hawaii, where geothermal energy resources are close to the earth's surface. California generates the most electricity from geothermal energy.
There are three types of geothermal power plants: dry steam, flash steam, and binary cycle. Dry steam power plants draw from underground resources of steam.
The three main uses of geothermal energy are: 1) Direct Use and District Heating Systems which use hot water from springs or reservoirs near the surface. 2) Electricity generation in a power plant requires water or steam at very high temperature (300 to 700 degrees Fahrenheit).
Geothermal energy is considered a renewable resource. Ground source heat pumps and direct use geothermal technologies serve heating and cooling applications, while deep and enhanced geothermal technologies generally take advantage of a much deeper, higher temperature geothermal resource to generate electricity.
Geothermal energy, one of the most promising among renewable energy sources, has proven to be reliable, clean and safe, and therefore, its use for power production, and heating and cooling is increasing. It is a power source that produces electricity with minimal environmental impact [3], [4], [5].
To extract geothermal heat, the hot water is pumped out of the deep subsoil and the heat is extracted using a heat exchanger. The cooled water is then pumped back and eventually heats up again because of the heat in the Earth.
Disadvantages of Geothermal Energy
- 1 Environmental Issues. There is an abundance of greenhouse gases below the surface of the earth, some of which mitigates towards the surface and into the atmosphere.
- 2 Surface Instability (Earthquakes)
- 3 Expensive.
- 4 Location Specific.
- 5 Sustainability Issues.
What are the Advantages of Using Geothermal?
- Environmentally Friendly. Geothermal energy is more environmentally friendly than conventional fuel sources such as coal and other fossil fuels.
- Renewable.
- Huge Potential.
- Sustainable / Stable.
- Heating and Cooling.
- Reliable.
- No Fuel Required.
- Rapid Evolution.
1 Environmental Issues
These emissions tend to be higher near geothermal power plants. Geothermal power plants are associated with sulfur dioxide and silica emissions, and the reservoirs can contain traces of toxic heavy metals including mercury, arsenic and boron.Unfortunately, geothermal power plants may have an unintended and potentially dangerous side effect: earthquakes. Whenever you drill miles into the Earth and remove material, whether it's steam, water or hot rock, you release pressure that causes the ground above the geothermal pocket to shift and subside.
Geothermal heating system price varies depending on the type of loop system, usually either vertical or horizontal. On average, a typical home of 2500 square feet, with a heating load of 60,000 BTU and a cooling load of 60,000 BTU will cost between $20,000 to $25,000 to install.
NOx emissions, especially Nitrogen Oxide (NO) – responsible for lung irritation, coughing, smog formation as well as for water quality deterioration. Sulfur Dioxide (SO2) – causing wheezing, chest tightness, respiratory illness as well as various ecosystem damages, especially acid rains.
