Geothermal Generated Electricity - is it a Viable Energy Option?

It is increasingly being recognized that the world has toelectricity in large power plants. Today, geothermal
replace fossil fuels with alternate fuels. This recognitionenergy provides about five percent of California's
is being driven by three premises:electricity, and 25 percent of El Salvador's. In Idaho and
First: Fossil fuels, coal, oil and natural gas, areIceland, geothermal heat is used to warm buildings and
accelerating in cost as they are consumed inother applications. In thousands of homes and buildings
ever-increasing amounts. The February 12, 2008 issueacross the United States, geothermal heat pumps use
of the Wall Street Journal has two articles tothe steady temperature just underground to heat and
re-enforce this premise. The first article, "China Spurscool buildings, cleanly and inexpensively.
Coal-Price Surge," by Shai Oster and Ann Davis,Physics of Geothermal Energy: Just a few meters
informs us that the price of coal out of Newcastle,below the earth's surface the temperature of the soil
Australia has increased from $40 USD at the start ofbecomes rather constant. You can depend on this
2007to $125 USA at the 2008. The article goes on toconstant temperature throughout the seasons. You
inform us that coal will join oil and natural gas in 2015can extract this heat in the winter to heat your house
as sources that are depleting.or to "bury" your heat in the summer to cool your
The second article, "The Future of World Oil Supply -house. Trench-pipe systems are utilized in areas
Filling the Missing Link," by Peter Jackson and Keithwhere ample space is available and well systems are
Eastwood ,informs us that the world's oil fields willutilized where there is limited space. It is within the
reach peak production around 2025 and then start atrench or well system that "coolant" is circulated to
rapid decline in production. Second: Oil and gas importsdeposit or extract the energy within the earth. As one
from foreign sources raise concerns over ourcan extrapolate, the further we reach into the earth
long-term energy security. We all have witnessed thethe higher the temperature will be. We have a great
jump in oil prices caused by wars, strikes and disruptedunderstanding of the heat transfer parameters for all
supplies. Gregory Meyers' article in the same issue ofthe zones of the United States. The physical
the Wall Street Journal cited Venezuelan Presidentparameters of this technology are beyond the scope
Hugo Chavez' threat to disrupt the supply of oil to theof this paper, but past successes in design have
USA because of a dispute with Exxon Mobil Corp.demonstrated our ability to harness this energy. In
This threat caused a 2% increase in the price of crudeaddition, we can gain a great benefit from our oil
oil.companies. The technology successes that the oil
Third: Burning fossil fuels dumps carbon dioxide andcompanies have had in drilling for oil can now be
other pollutants into the atmosphere. The dumping ofapplied to drilling for geothermal energy.
the pollutants is considered a fact. The severity of theGreat, How Much Will It Cost Us? An MIT study by
damage to our atmosphere is still being debated, butMIT Professor Jefferson Tester et.al., The Future of
most scientists believe that the future consequencesGeothermal Energy, a study of the potential for
will be very damaging to the quality and affordability ofgeothermal energy within the United States, found that
the lifestyles of our current and future generations.mining the huge amounts of heat that resides as
Fortunately, renewable energies are accelerating intostored thermal energy in the earth's hard rock crust
the forefront to replace fossil fuels, but will thecould supply a substantial portion of the electricity the
replacement be in time? Germany has adopted windUnited States will need in the future, probably at
and solar energies and is leading the world in thecompetitive prices and with minimal environmental
replacement of fossil fuels. These alternate fuels areimpact. It was their conclusion that geothermal energy
quickly being adopted in many countries to help replacecould supply 10% of our electrical needs by the year
fossil fuels. These countries provide a blueprint for the2050. This time frame could be accelerated if we, and
USA to follow and in replacing its dependence on fossilour government, adopted a more aggressive schedule.
fuels. The most popular replacements are wind andA conclusion from the MIT study ,mentioned previously
solar energy. Both of these technologies require us toestimates that a project costing $300 million US dollars
rethink our energy policies.to $400 million US dollars is needed to fund early
There is a third leg available for the replacement ofgeneration plants. The same study cites a US
fossils fuels, geothermal energy. This type of energygovernment study of geothermal energy which
offers us a potential to replace our coal fired electricalestimates that for every 100,000 nominally sized
generating plants by 2050. It is available and beingresidential units consumers will save approximately
utilized today. It is the third leg of the tripod that we$500 million over a 20 year time span in heating and
need to replace fossil fuels in time to retain our qualitycooling cost at today's prices. This estimate was from
of life. What is Geothermal Energy?.a 1993 US Government report. Installation of a heat
Geothermal energy is derived from the heat in thepump in a four-bedroom, 3,000 square foot house
interior of the earth. Geothermal systems move thesituated in the middle of the US would cost
heat from the earth into the home in the winter andapproximately $26,000.00. Payback at today's energy
discharge heat into the ground in the summer.cost of $0.09 per kilowatt would be in the range of 13
Underground piping serves as a heat source in theto 14 years. Government incentives and home
winter and a heat sink in the summer. In essence, it isappreciation are not included in this analysis.
the same heat-exchanging process used by theSummary: Geothermal energy is a tested and
common refrigerator or air conditioner. Heat from theavailable renewable energy that can be utilized to
earth can be used as an energy source in manyreplace fossil fuels today. Heat mining has the potential
ways, from large and complex power stations to smallto supply a significant amount of the country's
and relatively simple pumping stations. Examples of thiselectricity currently being generated by conventional
heat energy can be found almost anywhere. It can befossil fuel, hydroelectric and nuclear plants. The resolve
found as far away as remote, deep wells in Indonesiato replace fossil fuels with geothermal, wind or solar is
and as close as our own backyard.left to us and to our government. The technologies are
In the Western United States and in other placesavailable and ready to be deployed.
around the world, geothermal energy produces