Power is solvable through many inefficient sources

Power will not be the binding US constraint because beyond the three combined-cycle gas turbine makers there are 16+ gas power-gen vendors plus aeroderivatives, medium-speed reciprocating engines, ship engines, fuel cells (Bloom), and solar-plus-battery; even doubling power cost to ~$3,500/kW only raises a GPU's TCO a few cents/hour, and utility-scale batteries could unlock ~20% of the terawatt-scale US grid that sits idle outside peak hours.