[dvd3500]

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Three years ago, I looked into getting an EV for my wife, as most of her car use is local.  The car wasn't going to be cheap, plus I was quoted something like £3k to run the cabling from the house to the garage and supply and install the hardware, but I could have lived with that.  The whole upstairs of the house would have needed to have the floors up.  It's a 120-year-old house - can you guess where this is going...?

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Currently, the nearest public EV charging point to us is 4 miles away from us.

Moving away from internal combustion-engined cars just isn't an option around these parts, and is unlikely to ever be.

 I applaud that you looked into this and provided some info on your scenario. Yours is likely to be similar to many others.
There a few things I would like to point out:
1. 3 years ago things looked very. very different. technology has moved on, though frankly I don't think it will make a lot of a difference in the offer they made.
2. Any standard socket can charge any EV. We have 2 BEVs and one of them is exclusively charged form a standard European "Schuko" wall socket.  It pulls just under 3 KW . "But that will take forever!" I hear.. yes.. and so what? If you are charging from the grid you can charge overnight and your typical "park and then drive" time will be between 10-15 hours. That is enough to charge 20-45 KW. All you need charger cable that can be bought easily for about 200 of your favorite currency (LIDL had them on sale a few weeks ago). There are power companies that will PAY you to charge your car at night... (Octopus ... other companies are available).
In fact, I wish I could slow charging down on my cars because my solar panels fluctuate their output and  a nice 2-3 KW an hour is enough to cover the KW used on most trips.
If you need faster charging you can go somewhere else.
3. Check out app and webpages like PlugShare. My town will have over 90 charging points by the end of the year ranging from 11 KW to 300 KW. More are added often.

We have had solar for almost 4 months. 13 KW peak and a 10 KW battery. It is great. They only wanted to put in 9 KW but I told them to cover the roof as doing it again later would likely cost more and cause compatibility problems.
My town heavily subsidized our installation but guess what?
The prices have fallen so much that if I bought it now I would pay the same as I am with the subsidies, about 30%...

So back to the original question:

I can only speak for Germany as that is where I have lived most of my life and done most of my business.
Solar is often not installed simply because of crazy insurance clauses about who pays what when the panels are damaged or of the building gets damaged.
The other problem is the rent and upkeep are sunk in the operations and most companies don't care because short-term the panels will cost and bring no benefit.
The rules are changing though and buildings have to cover their energy needs by renewable sources more and more.
I think it has be something like 60% by 2040 or something (don't quote me)..
A lot more could easily be done though, you are right...

[Henk]

Here in the Netherlands the panels are subsidised too, you can claim the VAT (21%) back from the government.
Also we have no use for batteries (yet) because we can 'give" the electricity back to the grid. It's a net som in the end, what you use will be deducted from what you generate. This means that we can still run the washing machine at night, or use electricity in winter compensated by the surplus in summer.

We generate between 3400 and 3800 kWh per year, our use is about 2200 kWh, we get money for the surplus although it is not much, currently about 8 cent per Wh. In the end it will lower our gas bill (yes we're still on gas).

Since more and more people place solar panels the electricity companies run into problems, on a sunny day the current grid can not handle it anymore. The investments needed to improve the grid are enormous so things are starting to change. The government decided to make an end to the net sum arrangement per 2027, means we'll have to get a battery. Luckily the technology is developing fast, so in a couple of years the batteries will be able to store more for less money.

Also the privatised energy companies now start to charge customers for feeding back into the grid.

Electrical cars are (were) very popular, in the Netherlands the low milage is not a problem because the distances are low and we have a lot of charging points, many companies offer the possibility to charge at work. However the demand for electric cars is dropping, and in Germany even by 10% or so probably because they stopped subsidising. 

I myself have been looking at an electrical car but decided not to, I still think the milage is to low. When we were buying a new(er) car for SWMBO I talked to the sales representative, they had a BMW I4 in the showroom. This car is advertised as being able to do about 500km on a load, depending on the model. I asked him what the experience of his customers is, he told me that 500km is possible in perfect conditions but on the average the range is more like 300km. To get to my work in Hannover (Germany) I have to drive 360km single trip. With an electrical car I will need to charge (up to 80% in 30 minutes) once or twice. that means an hour delay on a 3 1/2 hour trip. So for the moment I will be keeping my petrol car, despite the fact that I can charge an electrical car for free!