I have watched Jeff Barrie's Kilowatt Ours twice, and the one bit of information that sticks in my memory is a simple equation:
Running a 500 watt space heater for a couple of hours is not just "like" burning a pound of coal. It actually does burn it - releasing CO2 and other chemicals, and leaving behind wounds in the landscape. Carbon footprint sounds way too friendly, though, when the results also include spills of coal ash sludge like the most recent one in Kingston, TN.
Part of my spiritual disciplines for Lent is teaching myself to really see what is coming through the outlet. Today three simple power meters arrived in the mail. I plugged in my little office fridge, and I'll soon see how much coal it takes every day to have cold sodas easily available. I want to be able to see through the smoke of convenience and habit.