Renewables are already there. In their "World Energy Outlook 2020" report the International Energy Agency reported that the world's best solar power schemes no

Renewables are already there. In their "World Energy Outlook 2020" report the International Energy Agency reported that the world's best solar power schemes now offer the cheapest electricity in history, and solar is still getting cheaper at around 15% per year. Wind is not far behind, and large scale battery prices are dropping at around 20% per year. These price curves have been pretty consistently dropping for nearly 40 years. With solar already the cheapest electricity ever known, just project one more halving, 5 years, and think what you could do with that. Solar is acknowledged to be intermittent, but that's the sort of problem that power engineers love. The cheapest electricity ever, but only during daytime, with wind in strength available intermittently throughout the day. How would you use that? Batteries obviously, to load shift. Move heavy industry and heating and cooling loads to the daytime peak. Tune aluminium smelters to run flat out during the day, and on low load with insulation overnight so the pots don't freeze up. Water desalination during daytime, storing the water produced. Link electricity grids east-west to prolong the hours of sun light for the overall grid. Produce hydrogen during daytime. None of that requires any technology breakthroughs, they're just another day's work. Do all that and coal power consumption will drop drastically, while using the world's cheapest electricity. Making these changes can just be background tasks, and will get us to 80% replacement of fossil fuels without any heartache. Recent modelling shows the sweet spot for renewables is actually around 400% replacement of the current grid, with that solving a lot of problems that were expected with the old thinking that we needed to replace coal with 100% renewables. And then, if fusion comes along, great. We can close off the remaining 20%.