The key enabling technology is to tie all the separate grids together with High Voltage Direct Current (HVDC) power lines. This technology is flying under the

The key enabling technology is to tie all the separate grids together with High Voltage Direct Current (HVDC) power lines. This technology is flying under the radar but it's getting cheaper very quickly and it allows for continent size electric grids. To give a sense of how cheap it's getting consider that there's a proposal to send solar energy from North Australia to Singapore using this tech. That's about 4000km distance total with about 3000km of that under the ocean. 4000km is very close to the distance from Seattle to Miami. If Singapore can afford this then for sure the US can dig around in the couch and come up with enough spare change to build this out.