>Coal is being replaced Wherever coal is replaced it is replaced with natural gas (occasionally with hydro and nuclear). >As long as renewable + storage + gas

>Coal is being replaced Wherever coal is replaced it is replaced with natural gas (occasionally with hydro and nuclear). >As long as renewable + storage + gas is significantly cheaper than coal/nuclear ... This is a red-herring. It wouldn't matter if solar and wind were free. We can't use them without fossil-fuel back-up, which today means coal or natural gas. This is also why natural gas companies are one of the biggest lobby groups for solar deployments. >(and "wind ain't blowing" is much less of a problem than you probably think) It's actually a huge problem. If the wind speed is too high, you can't generate electricity (due to risk of damage to the turbine). If the wind speed is too low, you can't generate electricity. But the elephant in the room is storage. You can always dump more and more money to over-provision your generation capacity (meaning that in certain seasons you would have a ton of generation capacity sitting around doing nothing). The problem is that we don't have storage figured out at all. >which makes them very predictable Yes as much as weather can be predictable. >and storage technology costs are improving as fast as production costs. To be clear, we don't have storage technology that can store enough energy to power a reasonably sized city (pop:~1m) for a few minutes, much less a modern economy for weeks. There is no such storage technology on the horizon either. You need natural gas as back-up. Maybe in certain geographic region you can build a pumped-storage reservoir (at a great environmental cost). Take a step back and look at the big picture. No region with a reasonable population is currently being powered by solar and wind even though there is huge amount of pressure to do so - why is that?