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Hot Rock Geothermal

Hot Rock Geothermal

Hot Rock Geothermal

(OP)
The current issue of "Skeptic" magazine has an article which discusses hot rock geothermal.  It's also known as Hot Dry Rock (HDR) or Hot Fractured Rock (HFR).  With all of the discussion about alternate fuels, this is one that I had not been aware of.  Apparently, the Australians have been doing this for several years.

http://www.aussiehotrocks.com/

What do you think of this as an alternative energy source, and why hasn't it been talked about more in the media?  
 

RE: Hot Rock Geothermal

dry rocks = dry subject?

Perhaps the eco-Mengeles of the world don't like it.  Most likely because it can be implemented without inflicting discomfort on the public.

RE: Hot Rock Geothermal

This seems to me to be a local geophysical characteristic. I cannot see why it would not work, but I do not know how common is to find this in different parts of the planet. We use a bit of geothermal here (W Canada), but is not quite cost effective yet; the downhole temperatures I do not think would allow to use it for much power generation.

<<A good friend will bail you out of jail, but a true friend
will be sitting beside you saying " Damn that was fun!" - Unknown>>

RE: Hot Rock Geothermal

There was an article in either National Geographic, Pop Sci or Pop Mechanics (can't recall which) a few months ago about Geothermal in situations with relatively small temperature differences.  It was pretty interesting but I must admit I can't recall any detail.

KENAT, probably the least qualified checker you'll ever meet...

RE: Hot Rock Geothermal

(OP)
I don't have the article in front of me, but I think it stated that the dry granite stays about the same temperature throughout the entire planet.  It's just deeper drilling in some places.

RE: Hot Rock Geothermal

Must be, because some wells I've drilled around here have been over 5,000m deep and nowhere as hot

<<A good friend will bail you out of jail, but a true friend
will be sitting beside you saying " Damn that was fun!" - Unknown>>

RE: Hot Rock Geothermal

for what it's worth, which ain't much, we use lake ontario as a heat sink, to reduce air conditioning costs (not that we've needed it much this summer !)

RE: Hot Rock Geothermal

I think the crust is supposed to be pretty thin in Cornwall where some geothermal energy is used.
But the Tick has the right of it.

JMW
www.ViscoAnalyser.com
 

RE: Hot Rock Geothermal

There's a Geothermal plant in down town Southampton UK as I recall, unless it's been closed down.

You used to be able to look out of the window of the shopping Mall (not Marlans or Bargate the big fancy new(ish) one whose name escapes me.  I always thought that was an odd location!

KENAT, probably the least qualified checker you'll ever meet...

RE: Hot Rock Geothermal

A place in Oregon decided to use geothermal wells as sinks for their AC system.  Published a paper about it, got lots of good press.

A few years later, a nearby new building did the same, drilled a slightly deeper well...had good results.  A few years later, and a few more buildings, a few more wells...the water table dropped...and building #1 started to have all kinds of problems.

The "dry" systems presumably are closed-loop, perhaps they avoid the above trouble, but I wonder.

RE: Hot Rock Geothermal

As far as I know, the Australian plants are still in the experimental/investigative stage.

There is a lot of debate in Australia at the moment regarding where we are to get our future energy. This is one of four sources that is being proposed including nuclear, solar, and clean coal(if that exists).

This is only available at one or two locations in south Australia.

 

RE: Hot Rock Geothermal

(OP)
When posting, please note the difference between HVAC geothermal and power generating dry hot rock geothermal.  The first one uses ground temperature to help with your heating and cooling.  The later creates steam to drive power turbines.

RE: Hot Rock Geothermal

(OP)
The Skeptic article I read did have some question about setting off earthquakes in fault-prone areas.  Also, cooling down of the granite could be a problem if too much H2O was pumped down.  You'd have to wait for it to heat back up.

RE: Hot Rock Geothermal

jmw, Got any links and/or info on geothermal in Cornwall? (personal interest)

- Steve

RE: Hot Rock Geothermal

Scrub that request, been doing some surfing.  (It really is amazing how many parts of Cornwall still have no gas)

- Steve

RE: Hot Rock Geothermal

I had peripheral involvement with the Los Alamos Labs Hot Dry Rock project in NM back in the early '80's.  The wells were drilled over a known geothermally active area (a caldera or extinct volcano) and was for power generation.  It is an area where hot springs are common naturally.  It is not quite a closed loop, and the area has a lot of sulfur in the rocks.  Turbines don't generally like sulfur.  They've recently tried a new tack:  

http://www.lanl.gov/news/index.php/fuseaction/home.story/story_id/2054
 

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