Assessment of Fuel Economy Technologies for Medium and Heavy ...

no effect on congestion as a result of degraded performance. However, increased truck traffic
as a result of the rebound effect could increase congestion. The effect is likely to be minimal
on most roads, but could be significant at times and locations where the roadway is near
capacity and where truck traffic represents a significant fraction of total traffic. An estimate
using marginal per-mile congestion costs from the literature suggests that the increase in
truck traffic volumes described above for the rebound effect could result in an increased
congestion cost (to all road users) in the range of $0.3 to $1.4 billion nationwide.
Safety impacts – Analysis in the concurrent paper developed by ERG suggests that fuel
economy regulations would have no appreciable effect on vehicle performance and therefore
no effect on safety as a result of degraded performance. Increased truck traffic volumes from
the rebound effect could be expected to cause an increase in the range of 80 to 360 fatalities
per year and about 1,600 to 7,700 injuries per year nationally. An alternative estimate using
marginal safety costs from the literature suggests that the increased truck VMT could result in
an increased safety cost (to all road users) of in the range of $0.09 to $0.4 billion nationwide.
Key findings regarding alternative approaches to reduce truck fuel consumption are as follows:
Fuel tax – To achieve reductions in fuel consumption of the same order of magnitude as
assumed in the analysis of the rebound effect (20 to 40 percent) is estimated to require an
increase in the fuel tax on the order of $1 to $2 per gallon, which would lead to a combination
of both reductions in truck VMT and increases in vehicle fuel efficiency. However, elasticities
of fuel consumption with respect to fuel price are not well-documented for freight trucks so
this estimate should be considered particularly uncertainty.
Congestion pricing – No analysis has specifically examined the impacts of a comprehensive
congestion pricing system on truck fuel consumption. Estimates for all vehicles have found
modest impacts, on the order of a 0.5 to 1.1 percent reduction in total fuel consumption if
congestion pricing were widely applied in the U.S., although this is based on data
extrapolated from only two simulation studies. This is the result of a variety of effects,
including a reduction in overall demand, shifting of demand to less congested periods, and
more free-flowing traffic during peak travel periods. Analysis of cordon pricing in London
and Stockholm has found very small impacts on truck fuel consumption, with minimal
impacts on truck VMT but some benefits through reduced truck idling. An upper bound can
be placed on the potential fuel savings from congestion pricing (or other highway congestion
mitigation strategies) by estimating the total nationwide fuel ―wasted‖ by trucks in
congestion. This figure is estimated to be no more than 640 million gallons, or about 2
percent of total truck fuel consumption.
Intermodal transport – The potential for truck-to-rail mode shifting through investment in
rail and intermodal infrastructure and other incentives has not been extensively studied. One
study of the Mid-Atlantic region estimated that an investment of $12 billion could reduce fuel
consumption by 42 to 114 million gallons annually, at a cost of $110 to $290 per gallon of fuel
saved. The findings of one study of the I-81 corridor suggest that an investment of $7.9
billion could reduce fuel consumption by 145 million gallons annually, at a cost of $54 per
gallon of fuel saved, while another suggests that an investment of $2.5 billion for the Norfolk
Southern ―Crescent Corridor,‖ also paralleling I-81 between New York and the Southeast,
could save 170 million gallons annually.
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