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.
1 comment:
I love this graph too, very pretty, thanks for sharing it.
About its immediate significance one has to be careful though
1) the large inefficiency linked with electricity production is probably not due to transportation but mere second law inefficiency in producing electricity from thermal.
2) transportation inefficiency is probably grossly underestimated since transportation means are mostly transporting themselves.
3) residential/commercial waste being low is a consequence that what's going out of the window is not considered waste.
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