Yes, I got many a goldfish off them, never lasted long. We seem to carry coal today in 5 gallon plastic cans, with the top cut-off, I watch them at the turn around, handing them up to fill the bunker. Never asked how many cwt to the mile, I think the coal comes from South America? I know the Polish stuff was not much good, and the shutting of the South Wales open cast has caused a lot of fires.
The problem is our railway engines were designed for Welsh coal, and we did not need spark arresters, British
and Antigua

one can see the different design. At the moment Joan (second picture) is out of boiler ticket, so Steam trains stop running when the line side grass is dry.
We all know all the narrow gauge trains in Wales together have less carbon emission to one transatlantic plane flight, but the Welsh government shut down the mine.
I can see the push for solar, but it is more down to storage batteries, and the big question is why have them in private housing rather than at the power plants? We are told batteries can no longer be put in the loft space, due to the risk to firefighters in a house fire, but how do the firefighters know where the batteries are? If they see panels on the roof do they back off just in case?
What I would like to know, is how many rented properties is there assess to the supply tails? OK with my house, I can easily fit a CT, but in high rise flats, well any flat, is there access to the meter tails within wireless range of where solar panels will go to tell the solar how much to reveres flow through the plug.