I suspect that's one of the ones that runs on certain sorts of solid fuel, such as this: https://smokecontrol.defra.gov.uk/appliances.php?country=s https://smo

I suspect that's one of the ones that runs on certain sorts of solid fuel, such as this: https://smokecontrol.defra.gov.uk/appliances.php?country=s https://smokecontrol.defra.gov.uk/appliances.php?country=s AFAICT these still require chimneys but presumably the smoke they produce contains fewer particulates than that produced by wood in a standard stove, hence allowing them in these zones. Presumably Asooka was thinking more along these lines: http://brightstove.com/ http://brightstove.com/ This looks very interesting, but appears not to be available.