I don't think so. Yes, LLMs use electricity. But they use electricity in the data-center, not in your home. That's very different, because it's cheap to transfer tokens from the data-center to your home, but it's not cheap to transfer electricity from the data-center to your home. And that matters, because we can build a data-center in a place where there's lots of renewable and hence cheap energy (e.g. from solar or from water/wind).

If you think about it, LLMs are used mostly when people are awake, at least right now. And when is the sun shining? Right. So, build a data-center somewhere where land is cheap and lots of solar panels can be build right next to it. Sure, some other energy source will be used for stability etc., but it won't be as expensive as the energy price for your home.

> This makes me wonder, would it be possible to pre-compue some kind of "rainbow tables" equivalent for LLMs?

Already happening. Read up on how those companies do caching prompt-prefixes etc.