How EV and PV can improve air quality

Originally it was a Twitter thread

The growing number of photovoltaic installations that are present on around 30% of houses in Poland (numbers for Q1 '22)  and most cars manufacturers gradually switching to electric cars brings some hope for better air quality (Poland has THE worst air quality in the entire EU and is in top 10 worldwide)

13 years - that's how old on average is a passenger car in Poland. Almost 32% of them are running on diesel, and quite often those cars are in poor technical condition.

Combine this with the fact that most of the electricity in Poland comes from fossil fuels (coal in particular - its share is up to 70%, but thankfully solar is rising)  and you can see where poor air comes from.
I've switched the cars in June 2021 - from the 2019 Seat Leon Cupra ST (if you're not from Europe - it's basically VW Golf R Wagon, but better looking ;) ) to the 2021 Tesla Model 3 Long Range. I was thinking about getting an EV already in 2019, but the charging infrastructure was really bad back then. Now (it's the end of May 2022) I drive it like I would drive an ICE car. But to switch most of the country (I understand it won't be possible to switch every single car to EV in less than 5 years) shows another problem - where to get this electricity needed for charging?
During the past year I did 14k kilometers across Poland and there's one thing that really struck me, especially in rural and suburban areas: the number of PV installations on single-family houses. While it's still only 16% of houses, it grows every month (even after the government changed the way how prosumers are billed). They've also changed the law regarding wind turbines, so we're back at adding them wherever viable.

Now let's think for a moment - a growing number of renewable energy and a growing number of EVs on the roads. If every EV could work as energy storage (we have a standard for this called V2G - Vehicle to Grid, but not so many cars have this option yet) we wouldn't have to invest in massive energy storage facilities. Relying less on fossil fuels for both transportation and energy at home, prolonged time to improve the grid (because more households would work like energy storage for their own needs, thanks to EV charging) would improve air quality significantly.
There are some issues though:
 1. Long-term storage: while Poland has quite a lot of sunny days, sufficient to produce enough energy for each house with PV installation from May to September, there are weeks (and months, like in winter) where there's not enough sun, so we still need to have a backup. Hydroelectric won't work for that as there are not enough places that could work as pumped-storage hydroelectricity (it works really well in Sweden and Norway for example). And we're still waiting for nuclear plants to be built, so until then we're stuck with coal and gas.
 2. New car prices - new cars and especially EVs are too expensive for average people. The old age of cars currently on the Polish roads is not an incident. Most people simply aren't wealthy enough to buy new(er) cars (and public transport doesn't exist in many places, or is not reliable enough). What could happen quite a bit would be an affordable convert kit (basically what you need is a battery pack and electric motors, and there are companies selling that already
 3. Buildings insulation - to switch from fossil fuels based heating in single-family houses and have it working efficiently requires improved insulation in over a million households. It would help both at winter and summer, as it would decrease the need for cooling in the summer (A/C) and heating in the winter (ideally with subfloor heating that has the best efficiency, combined with heat pumps). There are government-backed incentives for that, but it's still not enough for many people.

Systemic changes and more focus on the country's fleet electrification together with continuous investment in renewable energy would not only make us less reliant on fossil fuels but also improve air quality a lot. And given how much money is spent on treating people with lungs disease caused by bad quality air it would be worth it (but government would need to think long-term, not about only next elections)