Electric cars versus conventional cars
How "green" an electric vehicle is depends on how long it is driven and the source of its electricity.

Electric vehicle analysis wins prize

Ever wonder how green your electric car really is? A team of NTNU researchers answered that question — and won a prize for their work.

Researchers from NTNU’s Industrial Ecology Programme have won a prize for an article they wrote that compared conventional vehicles with electric vehicles (EVs).

The paper’s online publication in October 2012 ignited “a global debate over the carbon footprint of EVs and, during the month of its release, it was the most downloaded scientific article published by Wiley, the journal’s publisher,” a press release from the Yale School of Forestry and Environmental Studies, which owns the journal, said.

The article, “Comparative Environmental Life Cycle Assessment of Conventional and Electric Vehicles,” was published in the Journal of Industrial Ecology, which also awarded the prize, named after Thomas Graedel, a Yale professor who helped pioneer the discipline of industrial ecology.

The prize was awarded for the “Junior Author Best Paper,” which recognized the work of Troy R. Hawkins, the first author of the paper who was a postdoc at NTNU when the paper was published. Hawkins is now director of Life Cycle Assessment at Enviance in Pittsburgh, PA, USA.

“This paper is probably the most timely and useful life-cycle based comparison of electric vehicles (Evs) and conventional vehicles to have been published,” the judges wrote of the work.

The article points out that while EVs offer the potential for reducing greenhouse gas emissions, the magnitude of their benefits depends on assumptions about how long the vehicles will be driven and the source of their electricity. For example, the authors wrote, if an EV is only driven for 100 000 km, its benefits to the environment are indistinguishable from a conventional diesel vehicle.