I have to agree with Aredwood, people should be encouraged to charge after peak load times are over.
Most EVs can set a timer for charge to begin, specifically for this purpose. But on most power plans you don't need to, you can just plug in and charge when you get home. The easiest way to get people to set a timer would be to charge more during peak loading times and less during off-peak times, with smart meters in most homes this should be easily doable.
Charging for peak loading times can also encourage other behaviours that help. It is possible to set a heat pump to turn on and warm up the house before you get home so that it is only running on & off to maintain the temperature during the peak load time, this is better than getting home at 5:30 to a cold house and running the heat pump at full power until the house is warm - that is a lot of current draw if lots of people do that!
Another benefit of charging more for peak load times is that some people will consider buying something like the Tesla Powerwall which can be used to store power at the cheapest time of day and let you draw from that stored power when the power supply is at the highest price. This would actually help the power grid more than buying some solar panels.