This is being studied in the US, there is some detail about it in this article: https://www.theatlantic.com/politics/archive/2020/08/how-tru...

The Pacific DC Intertie supplies power to Los Angeles from hydro dams in the PNW over HVDC lines. https://en.wikipedia.org/wiki/Pacific_DC_Intertie

That's really cool, I didn't know India was doing that. I found this article a few years ago about a so-called "supergrid" that would produce a similar network across the globe.

https://spectrum.ieee.org/energy/the-smarter-grid/lets-build...

Yep.

If the people who run wild wonderful off grid (great channel) have taught me anything, it's that battery backup is essential.

How viable would that be in terms of maintenance? I presume it'd have to have a lot of failsafes or personnel that's assigned to some of the distant or at-risk grid sections, to keep things running smoothly and do repairs fast if something gets damaged.

That gets at an interesting point that if one country depends on energy from a far distant country for part of the day, then the defense of those power lines has immense geopolitical significance; similar to oil and gas pipelines.

Maybe the solution is to keep a lot of dirty petroleum or coal-based generation capacity around to use in an emergency or war, but don't actually use it.

As usual, there's a trade-off between efficiency and resilience.

With HVDC, would you be able to take advantage of the occasional solar storm?