Realistically, some are going to expect coal for three more decades. That's even if you believe in climate change and the need to largely get rid of fossil fuels by 2050.
India and China need to build their power networks rapidly and renewables can't do it alone yet.
But that sort of investment will be at risk as soon as battery technology becomes cheap enough.
And it's at risk already due to increasing renewables.
The first four of those Japanese 45 coal fired stations have already been canned.
