This is the real inconvenient truth: if we end fossil fuel use to salvage a livable climate, we will have much, much less energy overall. And this has to be done within the next 20-30 years. There is not some source out there ready to plug in so we can continue as we have.
Fission nuclear, for example, has a 60+ year track record and provides just a small percentage of overall energy. Fusion is not happening in anytime frame that would help us. Anyway, those only provide electricity, not the fire that an industrialized civilization needs.
Will wind and solar be ramped up? Sure, but they will not fill the fossil fuel gap. And right now, they cant be made and installed without fossil fuels. They’re electricity providers too.
Hydrogen? Not likely. Biofuels? Not if we’re going to feed 8+billion people. Hydropower? We’ve damed just about every conceivable river in the world.
The reality is there will be much, much less energy. Our challenge is to figure out how to use what little we have to do the things that will keep us alive AND give us a quality of life somewhat better than cave dwellers.