Care to share more about trash burning? I'd be surprised if people living in Krakow or Warsaw commonly burn trash.
A common sight in my area at this time of the year is a senior person driving up to a community dumpster in an equally old car with plates indicating not being from around here and looking for loose pieces of wood - typically furniture.
The sale of furnaces that would even fit something like this for burning was banned in IIRC 2018, but there's a backlog of still functioning ones that are used.
Anyone trying this in a city would have the authorities called on them, but deep in rural areas few care.
It's coming from the surrounding areas, not the city itself.
But people around the city and, frankly, in most of Poland still burn solid fuels and if you drive around these places the smell can be really terrible and the smoke color and density coming from some chimneys definitely doesn't look like a dry wood smoke. Such smoke is often a product of burning very low quality, super fine-grained coal or rather coal dust, which is the cheapest fuel available.
I was shocked on a recent trip to England where there was the smell of wood smoke in suburbia.
Renewable energy, one of the cheapest source of heat kwh/$, doesn't require electricity to function, cheap to buy/install if the place was designed for it, &c. I'm building right now and my main heater will be a wood stove.
If the air stinks both inside and outside of his house I would assume he's doing something wrong, even my cheap cottage fireplace insert from the 80s doesn't smoke the inside of my house.
We just installed a second woodburningstove in our house, https://www.contura.eu/en-gb .. and i mean you can mess up your fire by burning wet wood etc. or... paper i dunno.
But dried wood burns really clean, absolutely no smell INSIDE the house (wtf?!) and outside you see a thin whisp of smoke from the chimney.
I don't know about electricity prices there either.
Gas for heating is something every European nation should steer clear from, for strategic reasons.
Do you want cheap and efficient, or do you want locally built?