Geothermal Energy

GEOTHERMAL ENERGYBy: Larry Robinson, Seth Allen, Ryan Robinson

WHAT IS GEOTHERMAL ENERGY?

Geothermal energy: Energy drawn from the internal heat of the earth, either through geysers, fumaroles, hot springs, or other natural geothermal features, or through deep wells that pump heated ground water.

Used for Heating (heat source) and Cooling (heat sink) houses and buildings.

Also used for creating electricity.

A BRIEF HISTORY

1807: European settlers moved westward across the continent, they gravitated toward the springs of warmth. John Colter visited Yellowstone and encountered the hot springs leading to the term “Colter's Hell”. Also the city Hot Springs Arkansas was founded.

1847: William bell Eliot, a member of john C. Fremont survey, stumbled across a steaming valley, just north of San Francisco, California. Elliot calls the area “the geysers”, and he thinks he found the gates of hell.

1864: homes and dwellings have been build near springs to take advantage of the natural heat of the springs. This is also the first time this energy is used on a large scale.

1904: prints piers ginori conti invents the first geothermal power plant at the larderello dry steam field in Tuscany, Italy.

1921: John D. Wells drills a well at “the geysers” with intend of generating electricity. This becomes the start of the united states’ first geothermal power plant

A BRIEF HISTORY CONT…

1960: the country’s first large scale geothermal electricity generating plant begins operation. The first turbine produces eleven megawatts.

1977: The Department of Energy in formed. In the 1970’s geothermal heat pumps were introduced, 1990’s

geothermal residential heat pumps became popular.

MINNESOTA IMPACT

Geothermal energy is a very efficient way to heat and cool houses and buildings in the Minnesotan climate.

Potential of Geothermal Energy in MN is great enough to generate just as much power that all 104 nuclear power plants in the whole United States.

Cons of geothermal heating systems in Minnesota:

The majority of geothermal systems need electricity to work. And where does most of our electricity come from?

KEY TERMS/COMPONENTS

Indoor Heat pump Ground Loop

Vertical Horizontal

Flow Center Temperature Sensitive Fluid

HOW THEY WORK

The geothermal heat pumps work by having a temperature sensitive fluid run through the drain field.

The fluid is then Heated/cooled by the Grounds constant 50F-60F temperature then pumped back into the heat pump for diffusion throughout the house.

This fluid is then heated/cooled to be recycled throughout the system.

Different fluids are used depending on the seasonal temperatures. http://science.howstuffworks.com/environmental/energy/geoth

ermal-energy.htm

PROS

There is an enormous amount of thermal energy deep within the earth that is replenished at a very high rate.

*Renewable* Geothermal energy is not susceptible to price inflation like

crude oil. Lifetime costs of geothermal operations both residential and

generation plants are smaller then other types of energy. High Pay back rate. Are unaffected by the variety in Weather. It is always working day and night (24/7)

CONS

First cost for building electricity generation plants are very high.

Geothermal energy cant be transported to generation sites like nuclear and fossil fuels can.

Very Location Specific. Geothermal power is only sustainable (renewable) if the

reservoirs are properly managed.

ENVIRONMENTAL IMPACT

Water from geothermal sources may contain traces of arsenic, mercury, boron, and antimony they precipitate as the water cools causing damage to the environment it affects the water table.

Construction of Geothermal power plants can adversely effect land stability in the surrounding region.

Increased seismic activity