I love this graph from Lawrence Livermore National Laboratory illustrating the flux of energy through the US economy. Some things that surprised me:
1) The amount of energy wasted in the transport of electricity is staggering, slightly more than the total amount of oil imported (in energy equivilent units); technological improvement in that sector would make an enormous contribution.
2) Transportation, as I expected, is woefully inefficient. What I didn't appreciate was the magnitude, the energy wasted by transport is approximately equal to all the coal burned!
3) The residential / commercial waste is surprisingly low. One assumes that some fraction of that waste is insulation and so-forth, but even if you took a big bite out of that with building improvements, you wouldn't make a dent in the big picture. It boils down to this: if one's goal is to reduce waste (which is a very different goal than reducing consumption) then electrical and transport are the obvious primary targets.
