MIT-led panel backs 'heat mining'

[C1ay]

A comprehensive new MIT-led study of the potential for geothermal energy within the United States has found that mining the huge amounts of heat that reside as stored thermal energy in the Earth's hard rock crust could supply a substantial portion of the electricity the United States will need in the future, probably at competitive prices and with minimal environmental impact.

 

lefthttp://hypography.com/gallery/files/9/9/8/geothermal_thumb.jpg[/img]An 18-member panel led by MIT prepared the 400-plus page study, titled "The Future of Geothermal Energy." Sponsored by the U.S. Department of Energy, it is the first study in some 30 years to take a new look at geothermal, an energy resource that has been largely ignored.

 

The goal of the study was to assess the feasibility, potential environmental impacts and economic viability of using enhanced geothermal system (EGS) technology to greatly increase the fraction of the U.S. geothermal resource that could be recovered commercially.

 

Although geothermal energy is produced commercially today and the United States is the world's biggest producer, existing U.S. plants have focused on the high-grade geothermal systems primarily located in isolated regions of the west. This new study takes a more ambitious look at this resource and evaluates its potential for much larger-scale deployment.

 

"We've determined that heat mining can be economical in the short term, based on a global analysis of existing geothermal systems, an assessment of the total U.S. resource and continuing improvements in deep-drilling and reservoir stimulation technology," said panel head Jefferson W. Tester, the H. P. Meissner Professor of Chemical Engineering at MIT.

 

"EGS technology has already been proven to work in the few areas where underground heat has been successfully extracted. And further technological improvements can be expected," he said.

 

The expert panel offers a number of recommendations to develop geothermal as a major electricity supplier for the nation. These include more detailed and site-specific assessments of the U.S. geothermal resource and a multiyear federal commitment to demonstrate the concept in the field at commercial scale.

 

The new assessment of geothermal energy by energy experts, geologists, drilling specialists and others is important for several key reasons, Tester said.

 

First, fossil fuels--coal, oil and natural gas--are increasingly expensive and consumed in ever-increasing amounts. Second, oil and gas imports from foreign sources raise concerns over long-term energy security. Third, burning fossil fuels dumps carbon dioxide and other pollutants into the atmosphere. Finally, heat mining has the potential to supply a significant amount of the country's electricity currently being generated by conventional fossil fuel, hydroelectric and nuclear plants.

 

The study shows that drilling several wells to reach hot rock and connecting them to a fractured rock region that has been stimulated to let water flow through it creates a heat-exchanger that can produce large amounts of hot water or steam to run electric generators at the surface. Unlike conventional fossil-fuel power plants that burn coal, natural gas or oil, no fuel would be required. And unlike wind and solar systems, a geothermal plant works night and day, offering a non-interruptible source of electric power.

 

Prof. Tester and panel member David Blackwell, professor of geophysics at Southern Methodist University in Texas, also point out that geothermal resources are available nationwide, although the highest-grade sites are in western states, where hot rocks are closer to the surface, requiring less drilling and thus lowering costs.

 

The panel also evaluated the environmental impacts of geothermal development, concluding that these are "markedly lower than conventional fossil-fuel and nuclear power plants."

 

"This environmental advantage is due to low emissions and the small overall footprint of the entire geothermal system, which results because energy capture and extraction is contained entirely underground, and the surface equipment needed for conversion to electricity is relatively compact," Tester said.

 

The report also notes that meeting water requirements for geothermal plants may be an issue, particularly in arid regions. Further, the potential for seismic risk needs to be carefully monitored and managed.

 

According to panel member M. Nafi Toksöz, professor of geophysics at MIT, "geothermal energy could play an important role in our national energy picture as a non-carbon-based energy source. It's a very large resource and has the potential to be a significant contributor to the energy needs of this country."

 

Toksöz added that the electricity produced annually by geothermal energy systems now in use in the United States at sites in California, Hawaii, Utah and Nevada is comparable to that produced by solar and wind power combined. And the potential is far greater still, since hot rocks below the surface are available in most parts of the United States.

 

Even in the most promising areas, however, drilling must reach depths of 5,000 feet or more in the west, and much deeper in the eastern United States. Still, "the possibility of drilling into these rocks, fracturing them and pumping water in to produce steam has already been shown to be feasible," Toksöz said.

 

Panel member Brian Anderson, an assistant professor at West Virginia University, noted that the drilling and reservoir technologies used to mine heat have many similarities to those used for extracting oil and gas. As a result, the geothermal industry today is well connected technically to two industry giants in the energy arena, oil and gas producers and electric power generators. With increasing demand for technology advances to produce oil and gas more effectively and to generate electricity with minimal carbon and other emissions, an opportunity exists to accelerate the development of EGS by increased investments by these two industries.

 

Government-funded research into geothermal was very active in the 1970s and early 1980s. As oil prices declined in the mid-1980s, enthusiasm for alternative energy sources waned, and funding for research on renewable energy and energy efficiency (including geothermal) was greatly reduced, making it difficult for geothermal technology to advance. "Now that energy concerns have resurfaced, an opportunity exists for the U.S. to pursue the EGS option aggressively to meet long-term national needs," Tester observed.

 

Tester and colleagues emphasize that federally funded engineering research and development must still be done to lower risks and encourage investment by early adopters. Of particular importance is to demonstrate that EGS technology is scalable and transferable to sites in different geologic settings.

 

In its report, the panel recommends that:

• 
   
  
• More detailed and site-specific assessments of the U.S. geothermal energy resource should be conducted.
  
• Field trials running three to five years at several sites should be done to demonstrate commercial-scale engineered geothermal systems.
  
• The shallow, extra-hot, high-grade deposits in the west should be explored and tested first.
  
• Other geothermal resources such as co-produced hot water associated with oil and gas production and geopressured resources should also be pursued as short-term options.
  
• On a longer time scale, deeper, lower-grade geothermal deposits should be explored and tested.
  
• Local and national policies should be enacted that encourage geothermal development.
  
• A multiyear research program exploring subsurface science and geothermal drilling and energy conversion should be started, backed by constant analysis of results.

 

Besides Tester, Blackwell, Toksöz and Anderson, members of the panel include: geomechanics expert Anthony Batchelor, managing director of GeoScience Ltd. in the United Kingdom; reservoir engineer Roy Baria from the United Kingdom; geophysicists Maria Richards and Petru Negraru at Southern Methodist University; mechanical engineer Ronald DiPippo, an emeritus professor at the University of Massachusetts at Dartmouth; risk analyst Elisabeth Drake at MIT; chemist John Garnish, former director of geothermal programs of the European Commission; drilling expert Bill Livesay; economist Michal Moore at the University of Calgary in Canada, former California energy commissioner and chief economist at the National Renewable Energy Laboratory; commercial power conversion engineer Kenneth Nichols; geothermal industry expert Susan Petty; and petroleum engineering consultant Ralph Veatch Jr. Additional project support came from Chad Augustine, Enda Murphy and Gwen Wilcox at MIT.

 

Source: MIT

[InfiniteNow]

I generally dislike when people reply to a beautiful news article with a one word comment, but I suppose we only hate in others that which first exists within ourselves... so, that said...

 

Wow!

[Racoon]

Great idea, but I am a little confused.

Does this mean its a short term solution?, or that its immediately economically feasible?

 

 

"We've determined that heat mining can be economical in the short term, based on a global analysis of existing geothermal systems, an assessment of the total U.S. resource and continuing improvements in deep-drilling and reservoir stimulation technology," said panel head Jefferson W. Tester, the H. P. Meissner Professor of Chemical Engineering at MIT.

 

 

According to panel member M. Nafi Toksöz, professor of geophysics at MIT, "geothermal energy could play an important role in our national energy picture as a non-carbon-based energy source. It's a very large resource and has the potential to be a significant contributor to the energy needs of this country."

[InfiniteNow]

That is a good question, Racoon. I interpreted it to mean that we could get it up and running quickly and without too many required funds, not that we could only use this as a means of energy for a short while then would have to find somthing else... That was just my interpretation, though, and may be faulty.

[Zythryn]

I had the same impression, that we have the technology to do this now, and is therefore a solution available soon/now.

Heck, many buildings are already using smaller scale thermal heating/cooling. The system being built for me is supposed to cover 80-90% of my heating needs and much of my cooling as well.

[arkain101]

I like the geothermal concept for creating energy. It is such a great source of energy, we just need the creativity to extract it efficiently, cleanly, and safely.

 

If we went full out and built a hell of a big system, it could power a good percentage of the world, while we figure out how to adapt more clean technologies.

[arkain101]

PS, Is gravity a perpetual motion machine? In that it will always create pressure/heat at the core of the object?

[Turtle]

PS, Is gravity a perpetual motion machine? In that it will always create pressure/heat at the core of the object?

 

PS OT No. That nasty little thing called entropy I think> The Moon once had lava, but it is now cold as a witches....er...it doesn't have lava anymore. :(

 

PS BOT This geothermal energy was conspicuously absent from the President's State of the Union act last night in which he mentioned wind, solar, 'clean coal', and nuclear (it's pronounced nucular:lol: ) power electrical generation. B)

[arkain101]

PS OT No. That nasty little thing called entropy I think> The Moon once had lava, but it is now cold as a witches....er...it doesn't have lava anymore.

 

Yes but the stuff under pressure in the core of the moon, contains energy relative to the stuff outside the moon. If you go to its core, grab high pressure material, then open it up in a container of water at the surface, it should release that pressure as energy in heat form should it not? and the moment you take material from a core, new material takes its place.

 

Sure the moon may eventually cool down to a good average because its mass is quite low.

 

But if gravity is infact a force that feeds the source of the force (ie sucks in matter that makes more force) then on earth for example, the core is energy differentiation relative to the surface. right?

[Turtle]

Yes but the stuff under pressure in the core of the moon, contains energy relative to the stuff outside the moon. If you go to its core, grab high pressure material, then open it up in a container of water at the surface, it should release that pressure as energy in heat form should it not? and the moment you take material from a core, new material takes its place.

 

Sure the moon may eventually cool down to a good average because its mass is quite low.

 

But if gravity is infact a force that feeds the source of the force (ie sucks in matter that makes more force) then on earth for example, the core is energy differentiation relative to the surface. right?

 

:hyper: Certainly you have cobbled together some good material, but it's no shoe. In reality, one does not simply go to the Moon's core and 'grab' stuff; the heat released doing so is far greater than that recovered. There do exist engines which operate on low differences in pressure & temperature but they lack power. Perpetual motion, gravitational or otherwise, no! :naughty: Entropy, yes. :)

[arkain101]

Cheers...

 

But hesitates to drink...

 

:naughty:

[Turtle]

:)

"This environmental advantage is due to low emissions and the small overall footprint of the entire geothermal system, which results because energy capture and extraction is contained entirely underground, and the surface equipment needed for conversion to electricity is relatively compact," Tester said.

 

The report also notes that meeting water requirements for geothermal plants may be an issue, particularly in arid regions. Further, the potential for seismic risk needs to be carefully monitored and managed.

 

In mulling this over and then re-reading the article, the potential problems get the short shrift on a least a word count basis. The water issue I think is a case-by-case concern depending on a specific location. The seismic risk I think is very real, and not for the reason they seem to imply. Hard to tell, but I get the impression they mean that if an earthquake occured it may wreck the hole and/or generating plant. My concern is that tapping off heat that otherwise would remain deep underground may actually cause quakes.

Moreover, even though geothermal eliminates greenhouse gases (ostensibly reducing global warming), it is introducing heat into the surface system that otherwise would remain deep underground & so adding to the warming.

 

Damned if we do, and damned if we dont? :naughty: :hyper:

[arkain101]

hmm..

 

I have no idea their design for scale, but, I can't imagine a pinhole of heat compared the vastness of the sky holding in energy from the sun causing a difference.

 

I'd rather go with the earth beltching a little then the sun coming over for a party.

 

That is, shut down CO2 emissions, and go with eartly geothermal heat.

[Turtle]

hmm..

 

I have no idea their design for scale,...

I'd rather go with the earth beltching a little...

 

I shut off the computer,

& went to bed,

but couldn't sleep,

and this article kept running through my head. :cup:

 

So, here's select quotes from the MIT article:

... continuing improvements in deep-drilling and reservoir stimulation technology," said panel head Jefferson W. Tester,...

 

The study shows that drilling several wells to reach hot rock and connecting them to a fractured rock region that has been stimulated to let water flow through it creates a heat-exchanger ...

 

Even in the most promising areas, however, drilling must reach depths of 5,000 feet or more in the west, and much deeper in the eastern United States. ...

 

Of particular importance is to demonstrate that EGS technology is scalable and transferable to sites in different geologic settings....

 

First, a scientist named 'Tester' is just too funny! :hyper:

 

Next, and best, is the translation I have to aduce for the Reddened words and phrases. These guys plan to drill holes over a mile deep and then drop big bombs down them! :) :naughty: Having shot off a few cherry bombs in gopher holes and wells in my day, this sounds like a hoot! :hyper: Scaleable ya say? We got nukes that we can fire out of an 8" field artillery gun for crying out loud. Duck and cover boys and girls, wer're about to 'stimulate the reservoir.' :eek: :hihi:

 

May as well kill as many birds with 1 bomb as possible, so there's this too:

http://hypography.com/forums/earth-science/9890-plan-look-into-centre-earth.html

[CraigD]

PS, Is gravity a perpetual motion machine?

Gravity’s not a perpetual motion machine. It’s a fundamental force.

In that it will always create pressure/heat at the core of the object?

When stuff – such as the solar system’s proto-nebula, Planetesimal, and so on – is attracted into large objects like the planets, their cores contain a substantial fraction of the kinetic and gravitational potential energy of the original stuff (not all of it, as some is lost as ejected objects, light flashes, etc), mostly as heat. Gravity hasn’t created energy, but transformed it.

 

The Earth, or even the Moon, has a huge amount of stored heat. As the MIT panel in the article explain, it can be a very useful source of energy. About 8,000,000,000,000 watts of electricity worldwide already comes from it (geothermal power), in some places providing a large fraction of their total electrical power (eg: 27% in the Philippines, 17% in Iceland).

 

Existing geothermal power plants are literally just scratching the surface, taking advantage of naturally occurring hot spots in the Earth’s crust. If more advanced material and techniques can be developed, plants could drill deeper, supply thousands of times more power, enough for all our energy needs. But I’m just echoing what technologists like the MIT panel have written with more expertise and detail. Good stuff :confused:

[silverslith]

Go MIT.:)

 

One big advantage to this stuff is that big money can monopolise it. So it might actually get done.

Oil drilling tech is up to the task. If it wasn't for heat they couldn't get their oil out, and they regularly cap a hole with concrete because all they find is hot water. Dry rock geo is in its infancy, and yes you can use nukes to fracture the rock. But its overkill. Hydraulic pressure is a more usual solution to open up prexisting cracks in deep rock. Not as daft as it sounds if you do the math.

Although things like the 250000 cubic kilometers of magma in the yellowstone chamber are exciting and cooling it would save the US from obliteration in a supervolcano sometime, the ocean floor is much thinner and probably the best resource.

In NZ we have 20% electricity from Geothermal. as much as hydro. Still theres quite a few natural streams producing tons per second of 60-100degc water that are being ignored and other natural fields. Also with supercritical reservoirs around a volcano 20km offshore. (water decomposes into H2 and 02 in supercritical reses', nice sideline!).

:lol: