Twenty four hour a day winter heat for a live-aboard in New England is a different matter.

On Granuaile my heat for five years was a marinized brooder heater, essentially a coal fueled top loading heater designed to keep hen houses warm, run 24/7 with little work, and tick over unattended. Once running, standard was to do a daily shake, clean, and reload. This kept things running all winter. I could reload reliably after a 36 hour burn and sometimes 48 hours. Longer than that and there was not enough coal fire left to reignite a new load of coal.

I packaged the coal in paper bags that I could just drop in, eliminating dust at that end. I had a good fitting ash tray in the bottom so I did not have to do any shoveling, and I spritzed the ashes before moving them. Despite all these precautions and frequent vacuum cleaning, coal dust was ubiquitous by February. I was very happy to switch to diesel.

Meg will eventually have a small wood stove in the owner's stateroom or the afterberth or both but that's really for atmospherics, not 24 hour per day heat.