The half-trillion-year fuel supply - it's not solar (was Selling pow

From Nuclearinfo:
The total abundance of Uranium in the Earth's crust is estimated to be approximately 40 trillian tonnes.

,,,and from Wikipedia:
The oceanic crust is 5 km (3 mi) to 10 km (6 mi) thick[3] and is composed primarily of basalt, diabase, and gabbro. The continental crust is typically from 30 km (20 mi) to 50 km (30 mi) thick.

At the boundary with the lithosphere, the temp of the surrounding rock rise to 500 to 1000 degrees Centigrade.
No known material could even BEGIN to withstand the pressure of the overlying rock at anywhere near those depths and temps.

From NAtional Geographic:
The ambitious new mining projects are "ultra-deep" mines with shafts that are deeper than 2.2 miles (3.5 kilometers) in the ground, where temperatures rise well over a hundred degrees Fahrenheit (55 degrees Celsius) and rock shatters like glass.

There is only a limited amount of mass we can access on this earth. This is an unfortunate byproduct of gravity and limits to material strength. Thus the ACCESSIBLE uranium is far below what you posit and of course, you conveniently ignore the residual radioactive waste disposal problem,,,

The ONLY clean, relatively open ended power source we can readily access is solar and the most efficient way to do that is from orbit.

GAry 7