There's a whole lot of buildings that were designed with a coal furnace in the basement which heats water, and all aparments getting a bunch of water radiators.

There's a whole lot of buildings that were designed with a coal furnace in the basement which heats water, and all aparments getting a bunch of water radiators. A switch from that to, say, a typical American forced air system is a huge expense, and it might not be all that easy to design a system that is well balanced anyway given the small space for said ducts. So when a building association finds themselves having to replace the old furnace, given that getting a new coal furnace is now illegal, the pellets are seen as the reasonable, if not wonderful alternative.