Comments on: US Geothermal Lags Behind While Kenya Sprints Ahead

By: agelbert

agelbert — Tue, 08 Oct 2013 22:59:00 +0000

That is only up until now. As long as you have the same target temperature (about 600 degrees), you can, in theory, provide enough steam through feeder pipes to push the large turbines now used in nuclear power plants. Because these steam turbines capture secondary steam for energy, they can be up to 60% efficient. The increased size adds to their efficiency. It's just a matter of doing it. Unlike nuclear power plant heat, geothermal heat is a great investment for a giant centralized power plant. Don't tell me there are no geothermal hotspots capable of providing multiples of heat power a nuclear power pig can generate. That said, I'm certain Kenya, Indonesia and possibly Japan will beat us to it because their fossil fuel and nuclear power corrupting influence is less than ours in the U.S. oil oligarchy.

By: JamesWimberley

JamesWimberley — Tue, 08 Oct 2013 19:22:00 +0000

Wrong size. Nuclear plants are big (ca,1GW) and use large generators in the 500MW range. Geothermal plants are normally 50-100MW.

By: agelbert

agelbert — Mon, 07 Oct 2013 23:53:00 +0000

You said, “If this is successful could we drop down a hole in any location whatsoever that would provide geothermal energy?”

It’s not necessary to drill to the mantle. Yes, some areas of the earth’s crust are really hot close to the surface and volcanic areas provide a great geothermal heat source.

However, for the amount of energy a building needs, any place on the planet below ground level has enough heat below the frost line to obtain a practical amount (100% of heating and cooling with a heat pump) of energy.

For steam geothermal electrical power, you, of course need to go deeper. The U.S. Government has a web site showing all the best spots in the USA for geothermal power. Just Google it.

By: agelbert

agelbert — Mon, 07 Oct 2013 23:37:00 +0000

Well said. And the exact same turbines now used in nuclear power plants with exactly the same temperature operating ranges are a perfect fit for geothermal without fissioning fuel rods to worry about.

I would love to see these nuclear power plants scrapped and their turbines recycled for geothermal power! It would lower the costs of start up on a geothermal power plant considerably.

Somehow, I don’t think the nuclear power advocates would be too happy with that…

http://www.pp33.cc/uploads/allimg/130708/5-130FR22H00-L.jpg

By: beernotwar

beernotwar — Mon, 07 Oct 2013 19:48:00 +0000

I know from playing Master of Orion II that when you get to Deep Core Mining on the research tree your colonies become massively efficient. I hear there is a plan to drill down to the earth’s mantle. If this is successful could we drop down a hole in any location whatsoever that would provide geothermal energy? If we dig too far or suck out too much heat will Earth implode like Krypton?

By: JamesWimberley

JamesWimberley — Mon, 07 Oct 2013 18:35:00 +0000

The USA only has vast untapped geothermal resources if you include EGS – ¨hot dry rocks¨ – as well as conventional hydrothermal. The latter taps underground hot water reservoirs, which you find in volcanically active regions like the Rift Valley. EGS – which could in principle be used in half the continental USA – is still experimental; there are under half-a-dozen pilots being drilled in the whole world, including AltaRock´s Newberry well in Oregon.

EGS gets ridiculously little funding given its mindboggling potential and characteristics which make it the prefect complement to wind and solar. As you say, geothermal is a compact, safe and above all 24/7 technology. Reliability exceeds anything else, even hydro which can run out of water. All the risks are upfront. Once the wells are drilled, the reservoir stimulated by water fracking, and the small (50-100MW) conventional steam turbines installed, there´s nothing to go wrong.