While people are switching to lower wattage lamps to save a few amps, there is one huge elephant in the room that has been missed, - in terms of energy and pollution saving. Traffic light coordination.
In less busy areas we have all seen trucks and cars come to a halt, perhaps at the bottom of a hill, just because the light was red, not because there was another vehicle in sight. In the US I have seen a line of trucks forced to stop in this way, and then when they start again, they would use more energy and produce more pollution than a small town saves with light bulbs in a year.
With modern electronics it would be easy and cheap to devise intelligent traffic lights. I can't imagine why it has not been done yet.
