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.
federal energy law aimed to set new fuel-efficiency rules for trucks as
well as buses. (Photo: TTI)
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
"[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."