Peak time is actually outside of those hours. Off peak is like 10pm - 7am. Yes the sun doesn't shine then, but the wind is always blowing somewhere in the grid. Even now during the days there's so much excess renewable energy (mostly from solar) that a lot of retail electricity providers are giving away free electricity between 11am - 2pm. Another thing to note is that when it comes to EV charging most people will not be doing a full charge every day or night, it's mostly top ups.
But going back to my original point a Coal Powered EV is still cleaner than a petrol/diesel car.
There's other perks, whilst in theory you have moved the pollution to where the electricity is generated (usually in remote areas) it actually helps clean up the air quality where most of the population live in the absence of tailpipe emissions. 83% of Australians live in metropolitan or urban areas.
Whilst yes it will take time, you got to have some form of aspiration or nothing gets done and some targets (even if you don't meet them) otherwise nothing will happen.
Something something forest/trees..
(20min delay)