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Mantzy81 t1_iupdkat wrote

Reply to comment by vfstevens in Drilling 12 Miles Down to Tap Geothermal Energy by tonymmorley

This would not be a problem. The Earth is plenty hot enough - also, there's really no need to go down that deep. The temperature gradient of the Earth is, on average, about 30°C per Km depth. it doesn't take long to get water hot enough to produce steam to turn a turbine. Some geological bedrock is cooler (i.e. cratons, e.g. Canadian Shield, Russian, South African and Australian cratonic complexes). There are enough radioactive elements in the to keep things toasty for a good while - or at least till the Sun expands and destroys Earth so we should be okay till then.

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VRGIMP27 t1_iurd35i wrote

If they have a means of drilling down deep enough it makes me think we should make a lead lined enclosure that deep and just put our nuclear waste in there from our reactors.

Man-made geothermal deep enough down that it's contained and doesn't need active Cooling or storage facilities above ground.

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Mantzy81 t1_iuri0hd wrote

Storing nuclear waste below ground already is a thing. But drilling down would be a problem. It's inherently unstable to generate heat. We need to store it somewhere a) stable b) low heat (as we don't want a meltdown) c) where any storage vessel won't melt from environmental heat (so not too deep due to temp gradient or deep but in cold rock d) where it won't interact, if there are issues, that would affect groundwater.

We often use salt mines for this as salt is very good at reducing heat in the source, low permeability and also self heals. It's pretty ideal for storage of nuclear waste. A borehole wouldn't suit for all the reasons that a salt mine does.

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Mantzy81 t1_iuufutp wrote

I forgot to mention before, that if you had geothermal everywhere, you wouldn't need nuclear anyway. it's a very clean electricity production method.

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