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Author Topic: How much natural fission energy does the Earth produce, and where does it go?  (Read 5200 times)

Offline Geezer

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At the risk of being redundant, how much natural fission energy does the Earth produce, and where does that energy go?


 

SteveFish

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The biggest natural fission reactor is in the earth's molten core. It is in fact molten because of fission and is still heating up slowly. I haven't heard numbers, but I bet they are known because the size and temperature of the core and the insulating value of the crust are known.
 

Offline Geezer

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The biggest natural fission reactor is in the earth's molten core. It is in fact molten because of fission and is still heating up slowly. I haven't heard numbers, but I bet they are known because the size and temperature of the core and the insulating value of the crust are known.

Yes. I'm sure that's right. I'd like to know what the total energy production rate is as I'm wondering how much of it we might tap into without messing everything up. Much as we may hate the idea of using nuclear fission energy, it's interesting that we are sitting on top of a gigantic nuclear reactor.
 

Offline syhprum

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Although at first sight tapping the internal heat of the Earth with geothermal power plants would seem to be the greenest of power sources in practice it does not always work out.
There is always the problem of releasing various noxious gasses that can be hard to control. 
 

Offline Geezer

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Although at first sight tapping the internal heat of the Earth with geothermal power plants would seem to be the greenest of power sources in practice it does not always work out.
There is always the problem of releasing various noxious gasses that can be hard to control. 

Yes. I'm sure that's right. But if there is enough energy available, we might be able to figure out a way to control those releases.

So, how much energy is there?
 

SteveFish

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There was a relatively local (to me, U.C. Davis) expert on geothermal energy interviewed on our community radio station yesterday, so here is some second hand information without figures. He said that if all of human power needs were met by geothermal sources it would be hard to detect even a slowing down of the increasing heat of the core. Versions of the technology have been around for over 100 years, and there are simple (relative to coal and nuclear derived energy) ways to deal with pollution problems. In general I prefer my fusion reactor power plant to be 93 million miles away, and my fission reactor power plant to be 1 thousand miles away.
« Last Edit: 28/12/2010 19:41:12 by SteveFish »
 

Offline Geezer

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Sounds reasonable. I'm guessing the total energy generation rate must be a fairly spectacular number. "All" we need is a lot of heat exchangers to tap into this energy source. If we only let a little bit of the heat out, all the other "bad stuff" can be left in place. Not a trivial problem to solve I'm sure, but it might be a very good long term solution to our energy needs.

Renewables like solar, wind, tidal etc. will play an ever more important role, but I think there is a lot of concern that they cannot meet the demand.
 

Offline syhprum

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There have been numerous schemes suggested and companies started to lay cables to bring geothermal power from Iceland to Scotland and Germany but although the power losses would be tolerable even without superconductivity they never seem to get of the ground.
Considering the vast sums wasted on fusion research, mining H3 on the moon etc this would seem to me a much better scheme.   
 

Offline Pikaia

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According to Wiki the heat generated by radio-active decay is 30TW.

http://en.wikipedia.org/wiki/Geothermal_gradient.
 

Offline Geezer

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According to Wiki the heat generated by radio-active decay is 30TW.

http://en.wikipedia.org/wiki/Geothermal_gradient.

That's reasonably spectacular  :)

I think that would be 30 million megawatts, so if we "borrowed" say, 1% of it, that would be 300,000 megawatts.

That ought to make quite a difference.
 

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