GEOTHERMAL+ENERGY+-+Veronica

= GEOTHERMAL ENERGY = By Veronica :)

What is Geothermal Energy?

 * Geothermal energy is power extracted from the heat within the earth (the core), originating from the original formation of the planet (e.g. volcanic activity, solar energy absorbed at the surface). We are able to recover this heat as steam/hot water and use it to heat buildings, generate electricity etc.



Some Facts

 * Has been around as long as the Earth has existed
 * Geothermal energy is found at naturally occurring areas of hydrothermal resources called **geothermal reservoirs**, mostly are deep underground with no visible clues showing above ground. However, geothermal energy sometimes finds its way to the surface in the form of **volcanoes or fumaroles** (holes where volcanic gases are released), **hot springs** and **geysers**.
 * Geothermal resources are **near plate boundaries -** most geothermal activities occur in an area called the **Ring of Fire**, which encircles the Pacific Ocean[[image:RINGOFFIRE1.gif]]

How It Works

 * People around the world use geothermal energy to **heat their homes** and to **produce electricity** by digging deep wells and pumping the heated underground water or steam to the surface. We can also make use of the stable temperatures near the surface of the Earth to **heat and cool buildings**.
 * Hot rocks underground heat water to produce steam.
 * We drill holes down to the hot region and steam comes up. It is purified and used to drive turbines, which drives electric generators.

An Example
The United States leads the world in electricity generation with geothermal power. In 2009, U.S. geothermal power plants produced 15.2 billion kilowatt-hours, or 0.4% of total U.S. electricity generation. Seven States have geothermal power plants:
 * Because its location on the Ring of Fire, and its tectonic plate conjunctions, California contains the largest amount of geothermal generating capacity in the US. In 2007, geothermal energy in the state produced 13,000 gigawatt-hours of electricity. Combined with another 440 GWh of imported geothermal electricity, then geothermal energy produced 4.5 percent of the state's total system power. A total of 43 operating geothermal power plants with an installed capacity of nearly 1,800 megawatts are in California, about two-thirds of the total United States' geothermal generation.
 * Nevada has 16 geothermal power plants.
 * Hawaii, Idaho, and Utah each have one geothermal plant.


 * Top ten countries that produce the most geothermal energy (wikipedia):**

Energy Change Involved
From heat energy to kinetic energy, then to electrical energy (heat from hot rocks underground heat the steam, which powers the turbine and generate electricity)

** Advantages: Eco-friendly and Renewable **

 * Geothermal power plants don’t burn fuels to generate electricity; hence the emission levels are very low. They release __less than 1% of the CO2 emissions__ of a fossil fuel plant. Geothermal plants use scrubber system to clean the air of hydrogen sulphide that is naturally found in the steam and hot water.
 * Moreover, geothermal plants emit __97% less acid rain-causing sulphur compounds__ than are emitted by fossil fuel plants. After the steam and hot water from a geothermal plant have been used, they are injected back into the Earth.
 * Renewable - never run out

// Scrubber systems: diverse group of air pollution control devices that can remove harmful gases from industrial exhaust systems//

Disadvantages

 * Biggest problem: there are not many places that are suitable to build geothermal power stations - need suitable hot rocks, suitable depth and rocks above that can easily drill through
 * Sometimes a geothermal site may run out of steam, and may last for decades
 * Other harmful gases and minerals may come up from underground, and they might be be hard to safely dispose of

Here's a video of people using geothermal energy to heat houses, click in, scroll down and you will see it

Source
Energy Resources: Geothermal Power Geothermal Energy in California Wikipedia - Geothermal Energy
 * EIA Energy Kids - Geothermal**