If we could transmit power across vast distances like that then we wouldn't even need to bother with solar. We could build a thousand nuclear power plants in the middle of nowhere.

Unfortunately, power transmission suffers from line losses. Even a few hundred miles requires several hundred thousand volts to avoid losses. Maybe that's an easier problem to solve than fusion.

You'd JUST need to move current from AC to DC, and span the whole of earth with superconductor cables.

You know, easy stuff to build and maintain.

China has built a 1100 kV line for 12 GW with losses of only 1.5% per 1000 km.

source: http://en.people.cn/n3/2018/0622/c90000-9474097.html

Use the local electricity to crack water into H2 and O2. Release the O2, use the local electricity to compress the H2 into liquid hydrogen, pump in across the country. The pipes themselves are a storage facility.

That's impossible, unless you have an invention for extremely cheap superconductors that you've been hiding away.

I bet the power transportation cost and loss would be too significant.

Electricity transport losses makes that impossible.