Geothermal energy—geo (earth) + thermal (heat)—is heat energy from the earth.
WHAT IS A GEOTHERMAL RESOURCE?
Geothermal resources are reservoirs of hot water that exist at varying temperatures and depths below the Earth’s surface. Mile-or-more-deep wells can be drilled into underground reservoirs to tap steam and very hot water that can be brought to the surface for use in a variety of applications, including electricity generation, direct use, and heating and cooling. In the United States, most geothermal reservoirs are located in the western states…Read more>> energy.gov
THE BENEFITS OF GEOTHERMAL ENERGY
THERE ARE THREE BASIC TYPES OF GEOTHERMAL POWER PLANTS:
Dry steam plants use steam piped directly from a geothermal reservoir to turn the generator turbines. The first geothermal power plant was built in 1904 in Tuscany, Italy, where natural steam erupted from the Earth.
Flash steam plants take high-pressure hot water from deep inside the Earth and convert it to steam to drive the generator turbines. When the steam cools, it condenses to water and is injected back into the ground to be used over and over again. Most geothermal power plants are flash steam plants.
Binary cycle power plants transfer the heat from geothermal hot water to another liquid. The heat causes the second liquid to turn to steam which is used to drive a generator turbine….learn more>> www.eia.doe.gov
WORLD MAP OF PLANTS
The current production of geothermal energy from all uses places third among renewables, following hydroelectricity and biomass, and ahead of solar and wind. Despite these impressive statistics, the current level of geothermal use pales in comparison to its potential. The key to wider geothermal use is greater public awareness and technical support. (Information from the US DOE)
The geothermal resource potential map for the United States shows locations of identified hydrothermal sites and favorability of deep enhanced geothermal systems (EGS). www.nrel.gov
This geothermal map shows current and planned power generation capacity by state. www.nrel.gov
OPERATING AND DEVELOPING POWER PLANTS
Developing geothermal projects and operating geothermal power plants information aggregated from the Geothermal Energy Association. www.nrel.gov
WHAT ARE ENHANCED GEOTHERMAL SYSTEMS
EGS are engineered reservoirs created to produce energy from geothermal resources that are otherwise not economical due to lack of water and/or permeability. EGS technology has the potential for accessing the earth’s vast resources of heat located at depth to help meet the energy needs of the United States. energy.gov
EGS Fact Sheet- egs_factsheet.pdf
INSTALLED GENERATING CAPACITY ON OUR PLANET
Who are the top 25 nations when it comes to generating capacity. www.geothermal-energy.org
HOW DOES GEOTHERMAL COMPARE TO OTHER ENERGY SOURCES?
by Stephanie Watson
…The initial costs of geothermal energy are high — wells can cost $1 to $4 million each to drill, and installation of a home geothermal pump system can run as much as $30,000 [sources: REPP, Consumer Energy Center]. However, a home geothermal energy pump can cut energy bills by 30 to 40 percent and will pay for itself within 5 to 10 years [source: Consumer Energy Center]…. Read more>> science.howstuffworks.com
WHAT IS IT?
Nearly all countries that produce geothermal electric power also utilize direct use and or geothermal heat pumps.
The uses to which these resources are applied are also influenced by temperature. The highest temperature resources are generally used only for electric power generation. Current U.S. geothermal electric power generation totals approximately 3,087 MW or about the same as five large nuclear power plants.