We have a cheap and infinite source of electricity, it's called nuke power. The main obstacle to its adoption, as well as the source of its cost, is NIMBYism. That problem goes away once you decouple generation and transmission. Build nuke plants at the ends of the earth and ship huge quantities of hydrogen back to civilization.
Transportation and storage of hydrogen is a problem too. Most metals become brittle when they're exposed to hydrogen. This is one of the big hinderances to using hydrogen as a fuel.
