Elsewhere, we've discussed deep meson sites and the problem with powering them - the meson site can be utterly hidden, but fusion power plants stand out in a neutrino scan like flashlights on a dark night: it's an obvious point of vulnerability, since killing the power shuts down the meson battery. So the question is: what other ways can we power the thing?
The deepest hole ever drilled in the modern era - over 12 kilometers - is the Kola borehole in Russia. I'm thinking that, given the materials tech to produce superdense armor, the tech to produce fusion plants generating hundreds or thousands of megawatts, and the tech to produce 250 megawatt lasers and 500 megawatt fusion guns, our future-tech fictional cousins should be able to beat that by quite a lot. Oceanic crust runs roughly 5 to 10 kilometers (which raises the interesting point that we could have reached the mantle if we'd been able to do this underwater). Continental crust is a lot thicker at 30-50 klicks, but there are convenient spots such as the island of Hawaii and the Yellowstone caldera where the magma rises conveniently close to the surface.
This raises the interesting idea of siting deep meson batteries in the ocean depths, below a few kilometers of ocean, with power drawn directly from the heat of the mantle and all that ocean above to conceal the heat signature and shield the site from missile attack (since attacks at that depth would require specially designed missiles rather than your run-of-the-mill re-entry-capable space missiles, complicating the enemy's supply situation).
Question is: how much energy is there in the stuff, and can we tap it for a multi-hundred-thousand megawatt/second power source without having to redrill every few weeks when the stuff gets cold? Or is it only good for the kind of power level that can keep the crew of an SDB warm and snuggly while they wait for orders?
The deepest hole ever drilled in the modern era - over 12 kilometers - is the Kola borehole in Russia. I'm thinking that, given the materials tech to produce superdense armor, the tech to produce fusion plants generating hundreds or thousands of megawatts, and the tech to produce 250 megawatt lasers and 500 megawatt fusion guns, our future-tech fictional cousins should be able to beat that by quite a lot. Oceanic crust runs roughly 5 to 10 kilometers (which raises the interesting point that we could have reached the mantle if we'd been able to do this underwater). Continental crust is a lot thicker at 30-50 klicks, but there are convenient spots such as the island of Hawaii and the Yellowstone caldera where the magma rises conveniently close to the surface.
This raises the interesting idea of siting deep meson batteries in the ocean depths, below a few kilometers of ocean, with power drawn directly from the heat of the mantle and all that ocean above to conceal the heat signature and shield the site from missile attack (since attacks at that depth would require specially designed missiles rather than your run-of-the-mill re-entry-capable space missiles, complicating the enemy's supply situation).
Question is: how much energy is there in the stuff, and can we tap it for a multi-hundred-thousand megawatt/second power source without having to redrill every few weeks when the stuff gets cold? Or is it only good for the kind of power level that can keep the crew of an SDB warm and snuggly while they wait for orders?
(OK, not like the whole planet would go POP, but I'd rather not have that volcano triggered!) I'm sure residents of Hawaii are likely to have the same feelings, so maybe this experiment should be conducted someplace far from human habitation - maybe Mars? 
