>>538906503
Depends on a lot of things.
Maybe the cost is mostly the initial opening, maybe it's mostly for the actual high-speed travel, maybe it's how long it's open, maybe it's the size of the rift...
I could see something like this.
A solar panel station mostly in hyperspace collecting the intense light. (and possibly other electromagnetic energy)
A cable goes through a very small gate and connects it to a microwave antenna in realspace.