If you take the "350,000" H100s that Facebook wants by EOY, each of those can do 700W, which gives you almost 250 MW for just the GPUs. That sounds like a lot, until you realize that a single large power plant is measured in Gigawatts. All of Google's data centers combined are O(10 GW) which are matched with renewable power offsets [1].
Importantly, the world installed >500 Gigawatts of renewable energy in 2023 [2], mostly driven by PV Solar in China. The amount of potential solar and wind and other renewable-ish (hydro) outstrips even a 10x'ing of a lot of these numbers. But even for a single site, dams like Three Gorges are >20 GW.
There are real efficiency and scale challenges in doing AI in a single, large site. But existing power generation systems deliver plenty of power.
[1] https://www.gstatic.com/gumdrop/sustainability/google-2023-e...
[2] https://www.iea.org/reports/renewables-2023/executive-summar...
And third: renewables need to be associated with its backup like hydro/step or ... batteries which cost a lot. Gas can't be taken in as it's not CO2-free. All that unless training and inference happen when there's the corresponding wind and sun shining. And I'm not seeing that happening right now.