Sustainable Transportation Energy Pathways (STEPS)
Available online at: http://dx.doi.org/10.1016/j.enpol.2013.01.008
Yeh, Sonia and Daniel Sperling (2013) Low Carbon Fuel Policy and Analysis. Energy Policy 56, 1 - 4
The transition to non-petroleum fuels is proceeding slowly. Petroleum continues to dominate the transportation fuels market, accounting for over 95% of total supply. It has many advantages: It is very energy dense, easily transportable, and relatively abundant. But it also has large downsides: High carbon and toxic emissions when combusted and most of the lowest-cost sources are concentrated in a politically unstable region, the Middle East. Only Brazil has successfully shifted a large share of its transportation energy away from petroleum.