In our state, it is only woodburners and outdoor burning. Some folks in our valley are clueless and light their slash piles off during inversions which does more to smoke it up than wood stoves. I think our rules are copied from Collyfonia's. The bans generally start after a couple days of clear, cold, dry weather and last until a storm moves in. Usually November is a very nasty month weather wise, but we've had about a week of inversion. Last winter we skiers rejoiced in January or December. The valleys and base of the ski area were socked in with cold air and fog. The upper part of the mountain was clear with a warm breeze and even hit 50+ degrees one day. That lasted about a week. The good thing is that many areas of our state have "socialist" power companies and electricity is low priced as compared to other regions. 90% (I think) of our power comes from hydro. In fact, I maintain that my cost of heating with wood is comparable to heating with electric heat when I factor in the equipment/time/transportation costs. I like the constant heat of a fire and it gets rid of my friend's logging slash. My thoughts on passive solar come from visiting at a house that was built with a wall of windows facing the south. The rare days of winter sun provide so much heat in that house that windows have to be opened to cool things off. During the summer, the sun is blocked by their eaves. It takes some planning to do that right.