MIT-Led Study Says Geothermal Energy Is Viable

amigoro writes to tell us about a study for the US Department of Energy, led by MIT, indicating that geothermal energy could account for 10% of energy production in the US by 2050. The study concludes that geothermal is proven, could impose markedly lower environmental impacts than fossil-fuel and nuclear power plants, and is likely to be cost-competitive with the alternatives. This coverage in LiveScience points out how big a player geothermal already is in the US: "The United States is the world's biggest producer of geothermal energy. Nafi Toksöz, a geophysicist at MIT, noted that the electricity produced annually by geothermal plants now in use in California, Hawaii, Utah, and Nevada is comparable to that produced by solar and wind power combined."

Re:You heard it here first

[Cygnostik]

Actually, since it's the molten state of the magma as it churns and flows, the spinning of the core that creates the planet's magnetic field (like an electro magnet) - it's cooling would probably mean no more magnetic field and leave the planet to be bombarded with radiation from the sun among other things. The result would probably turn earth a little more like Mars. (inhabitable by humans to say the least)

Re:GeoWhoWhat?

[TranscendentalAnarch]

It's not really saying much for it. Not long ago I had an excel spreadsheet listing all of the power generating stations in the entire state of California including their power generation capacity. Of the over 37,000 registered power stations (this includes quite a few extraneous ones) Diablo Canyon and San Onofre together provided about 40% of the total power used in the state. The majority of California's power generation is Nuclear, Oil/Gasoline, and Coal based.

Re:Anti-nuclear bias

[TooMuchToDo]

"Former ORNL researchers J. P. McBride, R. E. Moore, J. P. Witherspoon, and R. E. Blanco made this point in their article "Radiological Impact of Airborne Effluents of Coal and Nuclear Plants" in the December 8, 1978, issue of Science magazine. They concluded that Americans living near coal-fired power plants are exposed to higher radiation doses than those living near nuclear power plants that meet government regulations. This ironic situation remains true today and is addressed in this article."

http://www.ornl.gov/info/ornlreview/rev26-34/text/ colmain.html [ornl.gov]

Re:Anti-nuclear bias

[Voice of Meson]

Um, I don't know about the others but I would not lump Australia in with those countries. Australia has one nuclear reactor which is primarily used for research and to produce radioactive materials for medical purposes.

It does not AFAIK produce any power for general consumption. Even if it does produce some it is misleading to say Australia has been "using nuclear power". We're all coal and gas over here. ?Luckily? we have shiploads of the dirty stuff.

Meet the Carnot cycle

[Goonie]

Nice try. Unfortunately, as I understand it, you can't beat the Carnot cycle [wikipedia.org] no matter what technology you use.

Re:Please don't mess with the ocean gradients

[InterGuru]

There is so much energy available that the whole world's energy consumption could be supplied with very minimal effect on the oceans. Quote below is from here [energybulletin.net]

Indeed, the Earth has an enormous natural solar collector - the tropical oceans. "On an average day, 60 million square kilometers (23 million square miles) of tropical seas absorb an amount of solar radiation equal in heat content to about 250 billion barrels of oil." [1] Energy "equivalent to at least 4000 times the amount presently consumed by humans." [2] If we can tap into this renewable source, considering thermodynamics and entropy, approximately 1% of it could provide the entire current worldwide demand for energy. More than enough energy is available, we only need a way to get it - in a practical, cost-effective, ecologically safe and sustainable way.

Re:Iceland!

[jrumney]

they run almost entirely off geothermal

Iceland gets 82.7% of its electricity from Hydro dams. Most of the rest comes from Geothermal though. The Philippines on the other hand get about 27% of their electricity from Geothermal - they're the number two producer after the US.

Re:Hope they won't produce earthquakes...

[rampant poodle]

Guess this is one of those lessons that has to be relearned every now and then. In the early 1960s a project to dispose of liquid wastes, (from Rocky Mountain Arsenal), by pumping them into deep drill holes caused a large number of earthquakes in the Denver, CO area. In 2004 a similar process was used to dispose of brine from a desalinization plant. A number of minor earthquakes quickly followed. Would guess that some Googling will reveal other incidents.

General opinion is that the injected fluids lubricate surfaces along shear planes in the fault line. Wonder if this could actually be put to good use, (many minor earthquakes as opposed to the Big One), in areas prone to big, infrequent quakes.

not pollution free

[peter303]

I worked for a company once that had geothermal as a side business and am aware of its short comings:
(1) The ground reservoir require constant "care and attention". Drill holes block up from mineralized water gunk much like some parts of the country see inthere house water pipes. Circulation pressure is fickle. It cant drop if there are new cracks in the rocks. You have to pump or re-drill.
(2) There are waste products- generally highly mineralized water that no one else can use. Hawaii is avoided geothermal development for this reason.
(3) A "dry" field may require a consistent water source. The US West is short on water supplies.
(4) You can set off earthquakes when you pump fluids. Rocky Mountain flats is the classic example, but this has happened to a lessor degree in the Salton Sea, CA and Geysers, CA area, both in seismic areas.

Still the benefits may outweigh the drawbacks. No carbon pollution.
Oil field and coal methane development have similar drawbacks too.