I installed a solar system at my home in Massachusetts for 17k last year (after tax credits), 7.82 kw. So far it's covered about 70% of my usage and 5.7 Mwh. I don't have a full year of data yet so I expect that number to grow as it includes the summer months. I drive an EV and this includes the car.
This is the problem still in the US. Even at ~$0.23/kwh delivered in the northeast, you're looking at an ROI of nearly five years. Fine if you can float that kind of cash to feel better about yourself, but the economics just aren't there for most people, especially in cheaper parts of the country where rates are ~$0.12. Even financing you're looking at a monthly payment equal to or greater than an electric bill. Of course if you have the time to amortize it you'll come out ahead, but there's simply no cheap solution that can actually save real money out of pocket in any reasonable amount of time beyond theoretical future savings on paper. It will never be a true solution without massive subsidisation that reduces out of pocket to a 1-2 year horizon.