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DEEP GEOTHERMAL DRILLING ON THE REYKJANES RIDGE...

Doesn't say they drilled into magma. Does say that an eruption occurred when magma broke into a bore. That resulted in the best parts of the drillfield becoming inoperable for 10-15 years. Obviously no one wants magma venting through their bores and so no one drills into magma.

In this magma layer, water collects in columns or reserves. This trapped water, which can be heated to temperatures of about 700 degrees Fahrenheit, is known as a geothermal reservoir. When engineers want to use geothermal energy, they "tap" in to this geothermal water and use the resulting hot water and steam for various purposes.

That's obviously factually inaccurate as magma is at least 700 degrees Celsius and any water in contact with magma will be heated to that temperature. And they are talking about using existing water reservoirs so they must be talking about Flash or Binary Cycle systems and not EGS systems. So they are not talking about drilling to the magma's level.

http://www.crest.org/geothermal/geothermal_brief_geothermal_resources.html

Which shows the hot side very close to the magma layer, with the injection well being farther away...

So again, no drilling into magma. You still haven't given one example of someone deliberately drilling into a magma chamber for geothermal power generation. The fact is that it is not done. EGS systems involve drilling to heated rock not magma. They may drill close to magma but that is not the same as drilling into magma.

A conventional Geothermal Plant *is* a deep drill plant... check out all the large scale ones around the world. The depths are different because the magma layers are at different depths... but they all drill to really close - or into that layer.

You seem to be confused about the different geothermal plant systems.

A conventional plant is not a deep drill plant. A conventional plant uses water that was already in the ground. In the case of Flash steam systems superheated water (in excess of 180 degrees Celsius) is allowed to flash to steam that drives turbines directly. In the case of Binary Cycle systems cooler water (between 100 and 180 degrees Celsius) is used in a heat exchanger. Both of these systems have been in production for decades and neither one requires deep drilling. The largest scale plants, such as those in The Geysers in California, and the plants in the Philippines are of this type.

EGS systems are still relatively new. They have been developed since the 1980's. They involve drilling to superheated rock and then pumping water from the surface to be heated (i.e. they don't use existing water from the ground). They still do not drill into magma. "Hot dry rock technology is meant to stay well away from the 99 percent of the Earth's interior, which is over 1,000 degrees". Note the "hot dry rock" alternate name - they don't want ground water for these plants. So there is not much point is using this helium technique to find locations for them. And also note that there are no EGS plants in the US.

I think you just misread the article. The title sums it up nicely though... "Helium isotopes point to the best sources of geothermal energy"

I didn't misread at all. You are reading stuff into it that is not there. They developed the technique by analyzing samples from the area surrounding the Dixie Valley geothermal plant in Nevada. That's not a EGS plant. Why would they test a technique for deep drilling on the area occupied by a conventional plant? They did that because they are looking for sites for new conventional plants, not EGS plants. As for the title, clearly the best sources of geothermal energy are those that don't require deep drilling.

I didnt bookmark that one.. but here are a few:

DEEP GEOTHERMAL DRILLING ON THE REYKJANES RIDGE...

Or

From: http://ezinearticles.com/?Producing-Energy-From-Geothermal-Resources&id=243735

Or

http://www.crest.org/geothermal/geothermal_brief_geothermal_resources.html

Which shows the hot side very close to the magma layer, with the injection well being farther away...

So, it's either close (drill to) or on/in (drill INto) it depending on which article/method...

The article speaks of using that method to find suitable locations that are "deep down" (from article)... not as a method of creating power... which still requires drilling and a geothermal plant. A conventional Geothermal Plant *is* a deep drill plant... check out all the large scale ones around the world. The depths are different because the magma layers are at different depths... but they all drill to really close - or into that layer.

I think you just misread the article. The title sums it up nicely though... "Helium isotopes point to the best sources of geothermal energy"

...(blah blah blah... but can now find what is deep below using this new Helium Isotope method... etc... etc...)...

"This suggests that, as deformation increases, fluids circulate more deeply into the Earth, thus scavenging up more of the mantle helium," van Soest says. "Areas where we can sample fluids near the surface provide a way of getting a relatively cheap and easy indication of what's happening deep down. Applying what we know about the helium ratios makes the exploration for geothermal resources cheaper and faster."

Googled a bit and found this with nice charts :) :
http://www.geothermie.de/gte/gte28-29/geothermal_e lectricity_productio.htm

http://ww.geothermie.de/iganews/no39/guadeloupe_ge othermal_developmen.htm

http://www.geothermie.de/egec-geothernet/basic/200 3_05_06first_shell.htm I was told that the hydrogen is sealed so good that you can even smoke when you are refilling hydrogen by a scientist from National Renewable Engergy Lab.

It is a pity about the chlorofluorcarbons. There is a good alternative process that uses ammonia and water that has been around for some time. It is more efficient than the straight water cycle, and the system is closed so the water isn't going anywhere. See for example http://www.geothermie.de/gte/gte46/geothermal_powe r_plant.htm

Here's another "tiny, little-known building" that uses the method. Involved quite a bit of drilling, but then again we're talking several GigaWatt-hours of heat transfer per year... (Web site only partially in English)

I'm not sure about "heard it first here".

Geothermal power has been generated from this plant since the 1950's. Geothermal generation comes with its own set of environmental problems and associated costs.