Casey Handmer is a huge solar bull and his estimate is that solar becomes cheaper than any other form of electricity even when generated from northern states by 2030 (likely sooner)

Iirc solar is meaningfully more efficient (30-50%) in southern states, so it will likely make sense to place energy intensive workloads in locations with more direct sun.

However, the cost of transmitting additional power is interesting and complex. Building out the grid (which runs close to capacity by some metric^) is expensive: transmission lines, transformers or substations, and acquiring land is obvious stuff. Plus the overhead of administration which is significant.

So there's a lot of new behind-the-meter generation (ie electricity that never touches the grid)^^

With all that in mind, I expect energy intensive things will move south (if they have no other constraints. Eg cooling for data centers might be cheaper in northern climes. Some processing will make sense close to where materials are available) But a significant amount of new solar will still be used in northern states because it's going to be extremely cheap to build additional capacity. Especially capacity that is behind-the-meter.

^ but not others! Eg if you're willing to discuss tradeoffs you might find dozens of gw available most of the time https://www.hyperdimensional.co/p/out-of-thin-air

^^ patio11 has a good podcast about this https://www.complexsystemspodcast.com/episodes/the-ai-energy... Disclaimer: my employer apparently sponsored that episode