You can get an estimate of how much new electricity will be needed by the GPUs already ordered but not delivered yet.
Tech companies that want cheap power for their data centers would make sense to buy facilities close to power plants, but savvy investors trying to profit off the market discrepancies would be investing in the forges and factories that can make the transformers domestically and start lobbying their congresspeople to get incentives from the DoE and other pork barrel spending to make building transformers cheaper and faster domestically. I think that will happen before we see the existing shortage lead to brownouts because energy demands are constantly growing, and both parties have incentives to grow domestic manufacturing.