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Introduction

Using Geothermal Energy

Using Geothermal Energy
Geothermal Technologies

Conclusion

Is geothermal energy practical?

References

Bibliography of Sources

U.S. Department of Energy

Geothermal energy is undoubtedly a form of clean, renewable energy, yet how does it compare conventional methods of generating electricity – by the burning of fossil fuels – and to other alternative energy sources? The categories below compare and evaluate the performance of geothermal energy in several categories.

Greenhouse Gasses and Air Pollution
Unlike fossil-fueled methods of generating electricity, geothermal methods emit very few greenhouse gasses or air pollutants. The most basic method of using geothermal energy – by capturing steam produced by the geothermal reservoir itself – emits the most CO2, yet the amount that such processes emit is still significantly lesser than that of fossil-fueled energy plants. The below graph contrasts the CO2 output of geothermal energy plants with that of conventional energy plants:

Credit: U.S. Department of Energy

Furthermore, more advanced methods of geothermal energy use – especially those that feature a closed system for the reservoir’s water – produce almost no CO2 emissions, for water used is pumped back into the reservoir instead of being released as steam into the atmosphere. Closed or restricted sytems, those that inject condensed water back into the geothermal reservoir after use in the system’s turbines, also greatly reduce air pollution – preventing the release of Hydrogen Sulfide, a sulfurous, volatile chemical that occurs with geothermal activity.

The Economics of Geothermal Energy
The use of geothermal energy can provide economic benefits, both to the region in which the geothermal plant is located and to the country in which the plant is situated. Geothermal energy is essentially free; costs are incurred only during construction of the plant and in the purchase of water to fill the reservoir or to replace lost reservoir water. Fuel is therefore extremely low cost, while the energy source – the earth’s tectonic activity – is extremely long-lasting. These factors establish geothermal energy as a relatively inexpensive and practical energy source.

Geothermal energy is inherently inexpensive, yet it can also have economic benefits for the country in which it is situated. Investment in alternative energy sources – including geothermal energy – reduces a country’s dependence on foreign sources of fossil fuels. According to the U.S. Department of Energy, “Nearly half of the U.S. annual trade deficit would be erased if domestic energy resources displaced imported oil.” (U.S. DOE: Geothermal Technologies Program). Additionally, most areas of geothermal activity – and thus geothermal energy plants – are located on federal land, providing a source of tax revenue that can be used to local benefit.

Although geothermal energy solutions are initially costly, their benefits are lasting, clean, and renewable. Geothermal energy – and other forms of alternative energy – is therefore a practical energy source.