Page 1 of 1

[PVpost] Geothermal?

Posted: 25 Jun 2005, 14:41
by PVPoster1
This is an edited re-post of a topic that existed before the forums were hit by a virus in June 2005. Please feel free to add comments at the end.

Geothermal is fine if you live in Iceland or on a volcano but it is no use and does not produce much energy and runs out.

Posted: 25 Jun 2005, 14:43
by PVPoster1
As i understand it Geothermal is one of our best hopes for future power generation, there are potential sites in the UK as well as europe, Italy has a geothermal power station that has been operating for 40 years +.

The UK resources are in cornwall which has good hot dry rock potential.

The worldwide potential for Geothermal is 50,000 times greater in energy terms than the fossil fuel endownment. If fossil fuels have lasted 200 years then the potential for geothermal is very large.

RE: Geothermal?

Posted: 25 Jun 2005, 14:44
by PVPoster1
I understand there are some issue to do with geothermal not being entirely renewable, as you need to put water back in to replace what comes out. There have been experiements in this, but it's not yet clear how successful they've been.

This applies to places where the site originally had hot springs, what are the possibilities for simply drilling pairs of deep shafts anywhere and putting water down one and getting steam out the other? I don't know if that works, or how deep you'd need to drill?

Posted: 25 Jun 2005, 14:46
by PVPoster1
Geothermal is accepted by most people as being renewable" due to the size of its resource.

Geothermal can operate on a closed loop system and any waste products are no where near as dangerous as nuclear waste so i firmly believe that heavy emphasis should be placed on Geothermal for future power generation. The electricity produced can be used for electolysis of hydrogen particularly at nights when demand is reduced.

The hydrogen could today be mixed with natural gas and burnt as normal in our gas appliances this in turn would extend the peak in natural gas production.

Geothermal is stored energy much like fossil fuels and would have a very high EROI.

Iceland are already proposing a hydrogen economy based on their abundant geothermal resources. They will even be able to export surplus electricity to europe through a proposed cable link which is still under review.

Heres hoping for a soft landing."

Posted: 25 Jun 2005, 14:47
by PVPoster1
Geothermal power is clearly limited by location. Iceland is well placed - and anywhere it can be tapped it should be. There is a rather fun restaurant on Lanzarote where they 'barbeque' meat using just geothermal heat....

There is always a but - and that is if you try to take too much heat too quickly from a geothermal source you will deplete it - basically cool it down. So the rate of replenishment of heat has to be taken into account with sources.

Geothermal won't solve our problems though - I don't believe there are enough locations.

Mike

Posted: 25 Jun 2005, 14:49
by PVPoster1
Mike T.

Your right about the over use of the resource, if pushed they can be damaged for some time, but we are just going to have to make more effort to get the balance right. If we dont then were just not trying.

There are many locations, and i bet we have not even looked very hard yet.

The holy grail of geothermal would be 6 Mile deep shafts, then its available just about everywhere (as long as the rock can be drilled)

Try to stay positive about Geothermal, its a huge resource.

Scorpio

End of PV posts

Posted: 08 Jul 2005, 07:38
by Peaked2Soon
The problem with Geothermal is the same economic problem that many alternative / renewable sources suffer from. While oil is cheap the alternatives seem expensive and uneconomic and so no one will make the investment. When the price of oil suddenly begins to rise as the peak is passed there will be a scramble to bring alternatives on line. Geothermal is a god option because it's pretty low tech.

digging

Posted: 24 Jul 2005, 01:05
by heinbloed
One needs to drill about 30 meters deep to achiev an increase of 1 degrees celsius. That is , as mentioned above , once the perma frost has been penetrated . But not many people live in these inhumane areas , unless they are drilling for oil or other funny things . Yes. The Inuit. O.K..
So a relative small depth is enough to heat homes or run a Stirling engine . But for high power , steam power plants , one needs higher temperatures . Drilling dry rock , that is expensive . But if oil rises further than every alternative is becoming cheaper , we shouldn't forget the technical progress in mining/drilling technology as well.. In former East Germany they were always short of " Valuta " for imported oil and so they started drilling . These boreholes are still delivering . 20 or 30 years after being drilled . Around Rostock as far as I remember , at the coast of the Baltic sea .
Excuse my bad English , please.