For years we had a little wood stove. It was in the dirt basement and we went up and down (what can loosely be called) steep steps 4 or 5 times a day to keep it stoked. I recon almost 2 hours a day was spent working on keeping a fire going down there. The last fire we had in it created a chimney fire which could easily have burned this old dry shack to the ground.
What is a chimney fire your may ask? Resins, creosote, flammable oils are created woods are burned, and over time, they build up and combust. It is worse with green or wet wood and a smoldering fire. Burning potato and orange peels helps reduce creosote. Unchecked, the chimney, up to the roof, is lined with creosote and when it burns you have a chimney fire. I can not tell you what it is like to watch the chimney in the center of your house shoot up flames and sit afraid that the walls will catch fire at any moment. There is nothing we could have done to stop it. By the grace of God, no harm came from it, but it was too close.
After this, and seeing the creosote dripping down the outside of the chimney we vowed never to have a fire in the house again. It was a really big investment for us, but we bought an outdoor furnace. Waterlines are hooked to the furnace, taking the heat to our house, running under the floor and with a little radiator keeping us very warm.
We fill the furnace box every 12 hours with 4 or 5 pieces of split log. This is 1/2 the amount of wood and 1/8 the amount of effort. It is very efficient, as it almost goes out (to conserve heat), then a fan comes on and starts it going again.
We grow the birch and larch, we burn to keep us warm, in our wood lot. It is very sustainable because birch comes back 6 fold when it is cut down, ie 6 saplings (approximately) grow up for each one cut down. The harder the wood the slower it burns, the more efficient it is. Cedar starts burning hot quickly, but too soon it is burned up. Birch bark also has a "flammable" component to the bark (paper) which makes it great fire starter too.