In a recent
finding submitted by Christoph Meinrenken of
Columbia University it is said that ;
Battery cars
powered by grid electricity promise reduced life cycle
green house gas (GHG) emissions from the automotive sector. Such
scenarios
usually point to the much higher emissions from conventional,
internal
combus-tion engine cars. However, today's commercially available
series hybrid technology achieves the well known efficiency gains in
electric drive trains (regenerative breaking, lack of gearbox) even if
the
electricity is generated onboard, from conventional fuels.
Here, They analyze
life cycle GHG emissions for commercially
available, state-of the-art
plug-in battery cars (e.g. Nissan Leaf)
and those of commercially available
series hybrid cars
(e.g., GM Volt, at same size and performance). Crucially,
they
find that series hybrid cars driven on (fossil) gasoline cause
fewer
emissions (126g CO2eq per km) than battery cars driven on current
US grid electricity (142g CO2eq per km). They attribute this novel
finding to
the significant incremental emissions from plug-in battery
cars due to
losses during grid transmission and battery dis-/charging,
and
manufacturing larger batteries.