NHTSA's Fuel Economy Impact Statement Should Be Revised to Be More Informative to Decision-Makers and Public

The
National Highway Traffic Safety Administration's (NHTSA) proposed fuel
economy standards would have the most significant positive effect on
climate change of any action taken by the U.S. government to date. They
would raise average fuel economy for the combined fleet of passenger
cars and light trucks to 34.1 miles per gallon in 2016. No single
policy can solve the climate change problem, but fuel economy standards
are critical to cutting emissions in the transportation sector, which
account for a third of emissions in the U.S.

Today,
NHTSA held a public hearing on its Draft Environmental Impact Statement
(DEIS). The DEIS is supposed to inform decision-makers and the public
about the relative impacts on greenhouse gas emissions from a range of
efficiency increases in light-duty motor vehicles. It does not serve
this function. The statement fails to consider all reasonably
foreseeable actions to control emissions from light-duty transportation
and fails to place the conclusions in a context that adequately informs
the public about the differences between alternatives.

The
analysis concludes that global warming cannot be stopped by five years
of fuel economy standards, trivializing the real, significant impact of
the standards. It is obvious that reducing motor vehicle emissions
alone will not stop global warming; we must reduce other sources of
greenhouse gases as well. But NHTSA should have assessed the
contribution that reductions in motor vehicle emissions could make.
Instead, NHTSA estimates that in 2100, the 2012-2016 standards would
reduce global greenhouse gas emissions by just 0.4 to 0.8
percent, without noting that U.S. motor vehicles are responsible for
about 4 percent of global greenhouse gas emissions. Placed in this
context, the reductions estimated by NHTSA are significant - 10 to 20
percent of motor vehicle emissions - as is the difference between the
alternatives.

NHTSA
also failed in its charge to produce a document that is written in
plain language and can be readily understood by decision-makers and the
public. The DEIS is a long, complex document that is inaccessible and
daunting to a layperson. For example, NHTSA discusses the annual motor
vehicle CO2 reductions from 2012-2100 in terms of equivalent
reductions from coal-fired power plants. This is no more meaningful or
accessible to the public than discussing motor vehicle emissions
directly. Presenting the impacts more clearly would significantly
improve the document's usefulness.