Maybe fusion will work. 5 more years to start testing test the first large scale reactor. 5 years minimum for more testing. Then say every country starts building right away, that’s another 10-15 years.

And that’s assuming everything goes smoothly and the designs work properly on the newly scaled up reactor.

Maybe fusion is the thing to save the world - but my perspective is our battle with climate change can’t wait another 20 years without phasing out fossil fuels, and we have tech now (solar, nuclear) that’s capable of replacing fossil fuels.