USA Energy Flows in Swanky Graphical Form
Critical to a productive conversation about energy in the United States is an understanding of what the current state of affairs exactly is. One of the best (and quickest) ways to do this is with Sankey Diagrams. Below are two diagrams of US energy flows, the first of which is from a 2007 Science article* by Whitesides and Crabtree (via Sankey Diagrams blog and Thoughts from Kansas). The second is from Energy Information Administration’s 2008 Annual Energy Review (via Sankey Diagrams blog).
Energy Flows, by Whitesides and Crabtree, Don't Forget Long-Term Fundamental Research in Energy (Science 9 February 2007: 796-798)
Energy Flow, 2008, in Quadrillion BTUs. From the Energy Information Administration's Annual Energy Review 2008
The two most interesting conclusions for me are the vast amount of energy lost within the US energy mix and how little energy within the country comes from renewable resources. Important in discussion of the first item is that not all methods of producing and distributing energy have the same room for efficiency improvements. You can’t pick out the largest slice of the pie and say we need to concentrate there alone — perhaps that area already is highly efficient, and a smaller chunk of the pie with higher gains from marginal efficiency improvements would ultimately yield a greater decrease in net energy demand. Secondly, in response to how little comes from renewables, both of these diagrams are for total energy use within the country, not just for transportation or electricity generation. Currently electricity generation and transportation needs are relatively separate, in that not many energy sources provide services to both. In the future this inevitably will change, as we come to drive more plug-in cars (or cars powered by natural gas), but in the meantime, we must be cautious in order not to conflate the two.
*: Don’t Forget Long-Term Fundamental Research in Energy
Whitesides and Crabtree
Science 9 February 2007: 796-798
DOI: 10.1126/science.1140362
Master of Public Policy candidate at the 
