Enhanced Geothermal Technology Could Power the Nation
Many of us have heard of geothermal power, when electricity is made from the earth’s heat using the steam from deep underground to drive a turbine and make electricity. In this country, most geothermal energy is made in the western states, but a new technology could make it more widely available.
Enhanced Geothermal Systems (EGS) is defined by the Department of Energy (DOE) as engineered reservoirs that can produce energy from geothermal resources that don’t have enough water or permeability in the rocks to make them economical otherwise. In essence, the technology drills deep underground – 10,000 to 30,000 feet - and “stimulates” the earth to get more energy from it.
A new report by scientists and engineers at the Massachusetts Institute of Technology (MIT) looked at the feasibility and economics of moving EGS onto the market and establishing it as a major source of power by 2050.
Major conclusions of the report include:
- EGS has the potential to supply the U.S. with all of its electricity needs.
- The environmental impact is limited because most of the work happens underground, the surface equipment is compact, and transportation costs and associated pollution are limited because of the resource's wide availability. However, the report does note that EGS runs a “manageable” risk of contaminating the groundwater and impacting seismic activity with its drilling.
- With “reasonable” investment in research and development, EGS could supply the country with 100,000 MW of electricity by 2050, at competitive rates.
Because of the time needed to get a commercial-scale prototype up and running, the MIT panel recommended that the U.S. start funding enhanced geothermal systems in the immediate future.
Daily Kos
U.S. Department of Energy
MIT: The Future of Geothermal Energy
February 13th, 2007 at 4:32 am
People tend to look at the long term effects of power sources such as oil and coal and say "look what they are doing to our ATMOSPHERE"… but what about our EARTH? If the earth itself was being used for power on an international scale which provided 90%+ of needed power (say, by the year 2200), then what effects would we have on our earth? We know by thermodynamics that:
m(h1+((C1^2)/2)+gz1)+Q=m(h2+(C2^2/2)+gz2)+W… simplified conservation of energy = [(Qin-Qout)=(Win-Wout)=Enet=0]
m=mass flow rate
h=enthalpy
(C^2)/2=kinetic energy
gz=potential energy
Q=heat
W=work
Which basically means that heat = work (both measured in W or [((kg)(m^3))/(s^3)] )
To get to the point, the more work we draw from our earth, the less heat it will retain. How long could one planet be used as a source of energy before it was "cold"? Could the move to geothermal actually end the problems with the atmosphere and begin all new problems with our earth? In X more years, could the human race be traveling from planet to planet just sucking all available energy from them and leaving nothing but distruction in its path?
A little si-fi, I know. I'd just like to get a few of these questions answered.
(50% engineer, 50% hugger, 100% PSU ARCHITECTURAL ENGINEERING)
February 13th, 2007 at 2:46 pm
Atlantic Geothermal followed the blog chatter after the publication of "Future of Geothermal Energy." The 62 blog headlines reflect strong interest from a wide range of groups, including environmental activists, the scientific community, the energy industry, and venture capitalists
Link: http://atlanticgeothermal.blogspot.com/2007/01/developing-story-response-to-mit.html
February 13th, 2007 at 11:33 pm
One thing not taken into consideration is that the earth is constantly "recharged" by the sun. Solar energy is absorbed by the earth on an ongoing basis. It all depends on the type of geothermal being used. Home systems use the solar energy trapped by the earth. Commercial systems often tap into geothermal vents deep in the earth. The question is how much can the sun recharge the vents, instead of just the surface?
July 7th, 2008 at 6:31 am
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