Although I see much more solar panels on houses in Poland than in UK
Perhaps that's more about where you live in UK and where I live in PL since I see the complete opposite.
There are new funding schemes in PL for solar, and heat exchangers are selling well.
I do know in UK a lot of people sell their electricity from solar to the grid.
Don't know if in Poland it's the same
Edit: Just confirmed you can't do that in Poland
PiS didn't allow it, and sadly the scheme was stopped for new users in the U.K. however this is likely to change soon after next month's election when Labour are back in as they should be,
This scheme (two way electricity metres) works well for farmers and especially for small scale water power. A small plastic waterwheel can generate a good amount of power, doesn't have the issues about storage that solar has, can run 24/7, doesn't need planning permission if you only have one, and is very cheap(from about £400) to buy. All you need is a stream with a decent flow.
but most people will only notice them for 30 seconds as they drive past
Agreed, and the part of PL that I live in isn't especially pretty. It's mostly flat and the countryside has been spoiled by ugly houses with plastic roofs and large numbers of billboards lining the main roads. They work well in towns; France has a new law that large car parks have to be covered by them.
present in Warsaw
They sometimes put braziers in bus stops in Warsaw on particularly cold days; it's not unusual for old people to freeze to death while waiting and this is intended to reduce that.