[geod_of_ix]

Where to even begin. 1. Temperature - The higher the temperature difference, the faster the loss of heat. How will the steam maintain it's energy (temp) in that long pipe. 2. Drilling each borehole is no small feat, and uses lots of energy and materials, all of which have associated embodied energy costs. Is is really worth it once all that work is done? 3. Geothermal. Interesting analogy, why not just use that instead. Boom, no additional radioactivity required. This whole things sounds very Rube Goldberg machine like.

[themaninthedark]

1. We currently produce steam using geothermal in similar situations. This is not a lot of information on depth on Wikipedia but I did see there was an abandoned plan to drill down 2mi at The Geysers and Reykjanes is 8,900 ft deep(1.6 mi) so I wouldn't worry about the ability to minimize heat loss.

2. The idea is to use the earth as a substitute for the containment building, so as long as the cost of drilling are less than those costs, it would be a net.

3. Geothermal is not readily available at shallow depths everywhere. The deeper you go, the higher the costs. Also with some types of geothermal you run the risk of earthquakes, as they use the same process as fracking to develop the wells.

[hughesjj]

Also for 1., why does the steam have to come all the way back up to spin a turbine? Can't you just have the Turbine down the shaft too? I get that there's other tradeoffs than that, but I figure the closer to the source the less leakage/parasitic loss there'd be

Unless the concern is that there's too little energy after going through the turbine that the water may condense and fall back down the "wrong side" of the pipe and add a bunch of resistance to the turbine.. although I'd imagine it might still be cheaper to do some one way valves and pump out the drainage pans while still being a net energy producer

[dirthacker]

Geothermal - just want to plug https://www.quaise.energy/

Millimeter wave drilling should help make this more broadly useful

[j-a-a-p]

And, supply of coolant versus the delivery of steam is constructed in a mile long heat exchanger. Perhaps this can be solved by high pressure, high flow - but if it for some reason halts for just a minute OP's little reactor is already in the China syndrome mode.