I live in a large house that has always been hard to heat, but I've always managed to pull it off. Until this winter,I was using just a colony hearth model c200 fireplace insert, which is adequate by itself until temps drop below 25f outside. Once temps drop below this, I was in the position of running the insert wide open constantly, and would go through tons of wood in a week. This winter I added a wonderwood stove to a room in the basement on the opposite end of the house from the insert, and the difference was striking. The house is staying very warm without a struggle. By adding an extra stove, logic says that I should have increased my wood consumption. The problem with this logic is that I seem to actually be using less wood. How could this be? The only explanation I can offer up is thus: each stove is being operated in its respective max efficiency range, which makes each stove need less wood. I will submit to you all that two stoves being operated at half throttle will use less fuel than one stove at full throttle. Could this be true?