As the federal government moves forward on a mandate
to set stronger fuel-efficiency rules for trucks and buses, a new
report from an independent scientific body is urging lawmakers to take
another approach: raise fuel taxes.
The National Research Council (NRC),
which often advises Congress and the executive branch on environmental
and transportation issues, yesterday reported on several strategies to
decrease emissions from heavy-duty vehicles.
Several
technological improvements scored high on the NRC's fuel-savings scale.
Adding hybrid powertrains to big rigs, for example, could cut fuel use
by up to 50 percent over five years, and phasing out gas engines in
favor of diesel-powered ones could achieve up to 24 percent in fuel
savings.
But the NRC's most surprising advice came on the
topic of higher fuel taxes, which the report described as an efficient
way to correct the "social inefficiency" that results when private
businesses decline to cut emissions "since the private return is too
low." The report also projected that higher fuel taxes would encourage
freight-carrying firms to make wider use of other gas-saving tactics.
"Although
the committee recognizes the political difficulty with increasing fuel
taxes, it strongly recommends that Congress consider fuel taxes as an
alternative to mandating fuel efficiency standards for medium- and
heavy-duty trucks," the NRC authors wrote.
Another benefit of
raising fuel taxes to spur emissions cuts, according to the report, is
the prospect of more immediate economic and environmental benefits.
"[A]
tax affects the utilization of vehicles already on the road, while fuel
consumption standards typically affect only new vehicles and can be
implemented only slowly over time as the vehicle fleet transitions to
the more fuel-efficient vehicles," the NRC authors wrote.
The report was produced in response to Congress' 2007 energy bill.
That legislation raised fuel-efficiency standards for cars to 35 miles
per gallon (mpg) by 2020 -- a target that the Obama administration has upped to 35.5 mpg by 2016 -- and called for new federal fuel standards for heavy vehicles such as trucks and buses.
However, academic researchers have criticized
the traditional mpg metric for failing to fully reflect the regulatory
benefits of reining in emissions at the least fuel-efficient end of the
scale. The NRC report takes the issue a step further by counseling
regulators to abandon mpg entirely for trucks and buses, instead using
a load-specific metric that rewards trucks stocked fully with freight.
Miles
per gallon "is not the appropriate measure for [medium and heavy
vehicles], since these vehicles are designed to carry loads in an
efficient and timely manner," the NRC authors wrote. "A partially
loaded tractor trailer would consume less fuel per mile than a fully
loaded truck, but this would not be an accurate measure of the fuel
efficiency of moving goods."