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Unpublished Paper
Environmental Efficiency of Automobile Energy Choices
Digital Commons (2016)
  • Peter V. Schwartz, California Polytechnic State University, San Luis Obispo
  • Chiweng Kam, California Polytechnic State University - San Luis Obispo
  • John Ross, Dr, California Polytechnic State University, San Luis Obispo
We introduce three efficiency metrics to compare two alternative transportation energy technologies: internal combustion engines (ICE) using bioethanol versus battery electric vehicles (BEV) charged from solar thermal electric (STE) generation. Both technologies require the use of the land surface area, consume water, and emit CO2. Travel efficiencies are measured in km per square meter of land used annually, km/L of water used, and km/kg of emitted CO2. Solar-electrical transportation utilizes land more than 200 times as efficiently, water more than 100 times as efficiently (when dry cooling of turbines is used), and emits less than 1/60 of the CO2 per kilometer traveled as does bioethanol combustion. 
  • biofuel,
  • effiency,
  • efficiency,
  • transportation,
  • sustainability
Publication Date
Summer August 23, 2016
This paper was rejected for publication from Science and Environmental Research Letters based on lack of market research considerations, such as "Would people actually use these cars?" There were also demands for additional computer models and consideration of other factors we were not able to accommodate. Lastly, the paper suffered from criticism from both sides of a pro and anti biofuels debate. Some people found our criticism of biofuels unwarranted and unsupported. Others found that we did not go far enough in condemning biofuel use. Since 2012 when the paper was rejected, several practitioners have expressed support for our findings and asked for the paper... so here it is.
Citation Information
Peter V. Schwartz, Chiweng Kam and John Ross. "Environmental Efficiency of Automobile Energy Choices" Digital Commons (2016)
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