Geothermal energy

[z]

About 'free' energy.

Geothermal energy will be near future stuff. That is to take the earths lavapools sufficiently close to surface in use - poor some water down, let the lava heat it up, add turbines and there you go: unlimited energy source. It would also be very close to zero pollution, because everything would happen deep underground, only electricity would come to the surface.

I saw from CNN the other day that US will start to tap these reserves seriously in near future.

Here some more info:

en.wikipedia.org/wiki/Geothermal_power#Potential

"The MIT report calculated the world's total EGS resources to be over 13,000 ZJ. Of these, over 200 ZJ would be extractable, with the potential to increase this to over 2,000 ZJ with technology improvements - sufficient to provide all the world's present energy needs for several millennia.[11]

The key characteristic of an EGS (also called a Hot Dry Rock system), is that it reaches at least 10 km down into hard rock. At a typical site two holes would be bored and the deep rock between them fractured. Water would be pumped down one and steam would come up the other. The MIT report estimated that there was enough energy in hard rocks 10 km below the United States to supply all the world's current needs for 30,000 years. [11]"

(ZJ - zeta joules)

[Caligastia Lanonandek]

Geothermal has been around for 30 years and is practical only in areas where the heat is very close to the surface. 10 km drilling isn't practical and transmission losses from the point of origin to the point of consumption are considerable.

[hollis]

Transmission loss within the rocks or across power lines?

[Caligastia Lanonandek]

Across power lines. Whenever you transport electricity over copper lines, you lose some of it to resistance and heat. The greater the distance traveled - the greater the loss. Line loss could be diminished substantially by going to a fiber optic structure.

[z]

I saw a comparative calculations from building a new nuclear power plant 1600 MW with a cost of about 5 billion euros and investing same amount to geothermal would produce 50 000 MW.

Since tunnels 50+ miles long are constructed through mountains and under sea makes me assume that drilling about 10 miles straight down is not that expensive. With technology improvements ofcourse.

Could this be right?

[Caligastia Lanonandek]

I don't think your assumptions to output on the geo are right.

To get anywhere near that number, you'd have to drill hundreds of holes.

[e-Male]

Aug 25, 2008 9:26:21 GMT -5 z said:

Since tunnels 50+ miles long are constructed through mountains and under sea makes me assume that drilling about 10 miles straight down is not that expensive. With technology improvements ofcourse.

Could this be right?

Don't want to be a bore , but the deepest hole to date is quite shy of 10 miles. 7.64 miles to be exact. An oil well in Qatar. Prior to that the Russians dug the Kola superdeep borehole (aka the Moho-hole) made it to 7.62 miles. en.wikipedia.org/wiki/Kola_Superdeep_Borehole

Boring straight down is quite different from boring horizontally. More heat and pressure involved.

Here are some other record bores besides me: hypertextbook.com/facts/2003/AdamCassino.shtml

/e

[z]

""Drilling at this depth is now possible in the petroleum industry, albeit expensive. (Exxon announced an 11 km hole at the Chayvo field, Sakhalin. Lloyds List 1/5/07 p 6) Wells drilled to depths greater than 4000 metres generally incur drilling costs in the tens of millions of dollars. The technological challenges are to drill wide bores at low cost and to break rock over larger volumes..""
( en.wikipedia.org/wiki/Geothermal_power#Potential )

- hmm. If the budget is in dollars about 7.5 billion.. And it 'could' go higher than 1600 MW what new nuclear power plant would produce.

I'm just thinking that new nuclear powerstation is being built here by a french company, no offence to french, but it really doesn't go right. Whole bunch of problems and it is seriously late in schdelules etc and the reactors are a prototype so.. Anyways, this geothermal energy has been brought up numerous times and I think I'll join this choir 'if' it in fact can actually produce energy and is not yet another 'windmill attached to a car' innovation.

[z]

Oh yeah.. and ruskies found hell from that hole ;D

- Serious lmao! One of the coolest hoaxes ever.

[Caligastia Lanonandek]

Z

Old One could 'burn' a drill hole to 10,000 feet (sorry, I refuse to speak metric) in about 20 minutes. Grind drilling is much more difficult. Also, you have to have 2 holes. One for the water to go down and another for it to come up. The only way this becomes remotely practical is if the magma is already close to the surface. This limits the number of possible sites and you're generally looking at remote regions so now you have to factor in line loss.

[z]

I calculated that if the budget is 7.5 billion and the cost is 'tens of millions usd' - ok lets put it to 90 million usd, we'd get 83 km of hole drilled.. Then assume that finnish ground is thickest possible = 42 km, we'd be 'just about there at the hottest spot' with two holes. One km would need extra funding

[z]

Checked that it was 70 km as its thickest, not 42 km as a I remembered.

Ok.. Not probably an alternative for finland then.

I'll jump to the other choir that promotes Fischer-Tropsch method in distilling fuel out from swamps.

Here's plenty of that stuff around: only 4 % of the swamps used would produce all the fuel what finland needs with current consumption. It is not used, because EU whines that fuel pollutes and has made a directive about banning the use of those reserves.. ..just straight from hitchhikers guide to the galaxy.

[Caligastia Lanonandek]

You could do the same thing with your sewers. Methan burns nicely and you're never gonna run out of the source.

AND I do know where my towel is

[e-Male]

Aug 25, 2008 15:56:39 GMT -5 Caligastia Lanonandek said:

You could do the same thing with your sewers. Methan burns nicely and you're never gonna run out of the source.

In fact, there's this contest called a "friefing" contest. Doesn't require a sewer. Just your own sweet self and someone to apply the flame. Rules do say: don't splotch, or you're disqualified.

Aug 25, 2008 15:56:39 GMT -5 Caligastia Lanonandek said:

AND I do know where my towel is

Funny, but you haven't struck me as someone who might panic under any circumstance. Why bother to keep track of the towel?

Z, I think that there are better ideas for obtaining geothermal energy than simply deep drilling. More distributed, less prone to systemic failure. All depends on the intended purpose for use for the power source. Just like you wouldn't want to consider wind power for a vehicle. Think of all the extra bugs you'd spatter in addition to the ones on the windshield. Plus low flying birds and overpasses become problematic. Not to mention the awnings at drive-thru windows.

/e

[Caligastia Lanonandek]

Why keep track of the towel? To avoid splotching