Comment by latentsea

Regional grids are connected via tie-lines, and I heard international grids are also starting to become more connected in this way too. Though, I'd imagine it's complicated to send power from one side of the planet to the other. For starters grids can have different frequencies that need to be converted between. Also all transmission lines are subject to loss factors. In addition all the intermediary transmission companies have to route the power and avoid congestion on their grids, Then you have deal with all the financial settlement of the wheeling charges, which if you have to go through multiple grids and multiple currencies sounds like fun to deal with.

My understanding of the intentions of connecting international grids is for things like emergency supply of electricity to a different grid to stabilise the frequency and prevent blackouts.