Let me start by saying we have two trucks, two cars and an antique car in our driveway. One truck my DH drives for a maintenance job with lots of tools. It is 13 years old and on it's last leg. The other truck just sits most days waiting to take over. He can only drive one vehicle at a time. One car is owned by my DS who is in university so the car is not on the road being driven at this point. His father gave him the car when he moved across the country. My DD lived with us for a year and a half and drove the other car back and forth to work. She moved out of the country so that car just sits most days. I carpool with DH everyday unless he or I have something to do after work (usually once a month) then I take the car my DD was using. I hang my laundry to dry as often as the weather allows. We recycle. We keep our thermostat set low. We turn off lights. In other words we try to reduce our "carbon footprint" as much as we can. But then we had a seminar at work about reducing green house gases and the claim was that the biggest waste of resources and the biggest cause of problems is not cars but buildings. Heating a huge building while not occupied overnight, leaving lights on in buildings overnight etc. Exhaust fans although necessary, are horrible. First you bring in fresh air from outside a building, then you heat or cool it using energy then you shoot it back outside and start the whole process again. And really there is no way around it to keep the air in working spaces fresh. It was a seminar on building management and I get it but I have no idea what to do to help. I will still keep doing my small part to help but when I sit and think of the sheer number and size of buildings that exist in the world, I find it mind boggling.