What is Geothermal Energy

How Does Geothermal Energy Work?

Just what is geothermal energy and what are its implications for today's energy needs? And how does geothermal heating work? This topic is receiving more attention lately in the context of global climate change and dangers associated with harvesting traditional fuel sources.

Geothermal power is considered a reliable, clean and renewable source of energy, which sharply contrasts with the limitations and pollution generated by fossil fuels such as oil and coal.

Sources of Geothermal Energy

The term geothermal originates from Greek words. "Geo", meaning earth, and "therme", meaning heat, define the heat within the earth as the source of geothermal energy. The core of the earth constantly produces heat that's hotter than the sun as its radioactive particles slowly decay.

This heat produced by the earth's core raises underground water to temperatures as high as 600 degrees Fahrenheit, which vaporizes and exerts extreme pressure on the ground above.

The answer to the question what is geothermal energy is dramatically demonstrated in the form of volcanoes, geysers, hot springs and fumaroles in locations such as Yellowstone National Park in Wyoming or sites in California such as The Geysers.

Current Uses of Geothermal Energy

The typical consumer may wonder how does geothermal energy work, and what is geothermal energy used for, since this power source hasn't been widely advertised. According to the report titled Lund and Freeston: WorldWide Direct Uses of World Geothermal Congress 2000 the United States ranks 2nd in annual worldwide geothermal power use.

In 2010, the United States produced the highest amount of geothermal electricity from its 77 power plants, located primarily in the geothermal fields of California. Geothermal power is currently used in business such as greenhouses and fisheries.

Home heating via geothermal heat pumps is one of the fastest growing applications of geothermal energy. In addition, 89 percent of Icelanders utilize geothermal energy for home heating. The city of Reykjavik uses spent water from geothermal plants to melt snow on sidewalks and pavements.

Where to Find Geothermal Power Plants

To learn what is geothermal energy and its role in overall power production, just look to The Geysers in Northern California. The Geysers covers a 45square mile area and houses 15 geothermal power plants. These plants created energy sufficient to power 725,000 homes. These types of power plants harness geothermal energy using one of three methods: dry steam, flash steam and binary cycle.

How does geothermal heating work? Power plants in The Geysers use dry steam technology to tap the underground stream and rotate turbines, which then produce electricity. Flash steam technology captures steam created when water reaches temperatures of 360 degrees and boils into steam.

Binary cycle power plants use lower temperature sources of heated water by vaporizing the water through heat exchange and creating their own steam.

Pros and Cons of Geothermal Energy

Although geothermal energy may sound like the answer to the rapidly rising energy needs of the world, it's important to consider what is geothermal energy and its development advantages and disadvantages.

Advantages of Geothermal Energy

The plus side of geothermal energy is that it is a reliable and plentiful source due to the earth's natural recycling of water and continuous heat from its core. Geothermal energy is sustainable because used steam can be condensed back into water form and sent back into the ground to reheat naturally.

Emissions of greenhouse gases such as carbon dioxide are only 1 percent compared to a power plant, which uses fossil fuel. The size of a geothermal plant is much smaller in comparison to gas and oil production industries.

Geothermal Energy Disadvantages

One of the most obvious disadvantages is the lack of natural sources of geothermal power. National parks such as Yellowstone are protected from such development. Creating artificial geothermal vents has historically been impractical due to the risks and the need to drill to extreme depths.

Lastly, since natural geothermal locations are dynamic and subject to shifts in the availability of water and tectonic activity, the source can unexpectedly shut down.

Future Geothermal Uses

What is geothermal energy role in the world's pursuit of alternative energy? Much of it depends on the development of safe and economical technology for tapping geothermal sources. Fracturing heated rock at great depths in order to infuse water, thus creating an artificial steam source, has risks to the environment that may not yet be known.

Although there widespread agreement that geothermal energy qualifies as a green technology, it must also become sufficiently costeffective to receive the research funding that is needed.

As you can see, asking what is geothermal energy generates a great deal of discussion and even more questions. Geothermal energy's role in powering the world continues to be examined as a viable alternative to the world's dependence on fossil fuels.

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