my daughter and son-in-law just installed a fireplace insert in their living room, and it's a marvel! they keep their house very cold, but being athletes, they and their kids don't seem to mind. the living room fireplace was a nightmare.  they used it once a year on christmas eve, and by christmas morning, the house was frigid from the air escaping up the chimney.  anyway, they got this lovely insert, and it's changed the whole comfort level of the downstairs.  they still keep the furnace set at about 60 degrees, but i can read on the couch without having to wear my coat and gloves.
it looks beautiful, too. what a great idea!  

Umbra says,"you don't want to regularly burn more fuel in the home just to get some atmosphere."

I think that's exactly what Brona wants to do.  If Umbra lived in Ontario, she might want the same thing.  Let's leave off the guilt-trip, and recognize that each of us makes choices, everyday, about how we impact the earth (not to mention the people around us.)

I'm sure there are things in Umbra's life that would make other environmentalists cringe, just as there are in mine.  I "waste" electricity keeping up my fishtank.  Watching fish (like watching a fire?) sooths my soul.  If you ever saw me "unsoothed," you'd tell me to keep the fishtank, environment bedamned.  

I refuse to call myself an "environmentalist" because of this holier-than-thou attitude.  

My fireplace has glass doors with a lever that lets me control the amont of air that flows into it from the living room.  It also has air chambers in the masonry that heat up and fans behind the vents to pull cold air out and send warm air back into the room.  While not nearly as efficient as a good stove, I think it provides a net gain - that is I get more heat than I lose up the chimney.