NTRD-02 Final Project Report The Effects of Low Rolling Resistance ...

1 INTRODUCTION
Through Project NTRD-02, the Houston Advanced Research Center (HARC) funded research
under TCEQ’s New Technology Research and Development (NTRD) program to evaluate the
emission reduction potential of a specific fuel-saving technology selected from the U.S.
Environmental Protection Agency (EPA) SmartWay Transport Partnership. The SmartWay
program is aimed at reducing emissions and improving fuel economy in the transportation sector.
Of specific interest for this grant was the application of SmartWay technologies to drayage
trucks operating in the two major non-attainment areas within Texas. Drayage operations in the
Port of Houston and at a freight locomotive terminal in the Dallas-Fort Worth are believed to be
significant sources of emissions of the oxides of nitrogen (NOx).
Drayage operations include inter-modal haulage between shipping and rail operators and their
warehouses and customers. A large proportion of the cargo is in shipping (often called “cargo”)
containers, and much of the remainder is in box vans. Most of the trips are less than 30 miles in
length and include long periods of stop-and-creep, idling, and short bursts on the highways. As
such, the range of loading on the trucks is broad and, up to the present, there has not been a
standard characterization for operations in the major air-quality non-attainment areas in Texas.
The first part of this project was to characterize the operation of drayage trucks in Texas at the
Port of Houston and the freight rail terminals of the Dallas-Ft. Worth metroplex. Specifically,
we logged data from drayage truck operations in and around the Port of Houston and the Dallas-
Ft. Worth freight rail terminals and used this logged data to develop a standardized Texas
Drayage Truck Cycle.
The second part of the project was to use the new standardized test cycle to characterize a
particular technology for reductions in fuel consumption and NOx emissions: the Michelin X-
One tire, which is designed to reduce a vehicle’s rolling resistance and inertial mass, resulting in
improved fuel economy and reduced tailpipe emissions. With sponsorship from TCEQ/HARC,
the University of Texas (UT) undertook a study to determine whether the new tires result in
reduced NOx emissions when used on drayage trucks. During the final task of this project,
drayage trucks were driven on a test track with the new low rolling resistance tires and with
standard tires to quantify the effects on tailpipe emissions and fuel economy.
At the time of this study, the Michelin X-One wide-single tires were unique in the market due to
their combination of light-weight and low rolling resistance compared to conventional dual tires.
Michelin X-One wide-single tires have already been the subject of Phase I and Phase 2 testing by
the EPA for Class 8 line-haul trucks (Bachman et al., 2005; Bachman et al., 2006). Michelin has
shown that these tires provide a fuel economy benefit for a variety of heavy-duty truck
applications and that these wide-single tires do not damage the roadway, unlike earlier attempts
(in the 1980s) at introducing such tires. Michelin has also shown that these tires provide
improved emergency maneuvering capabilities. In fact, the improved fuel economy from use of
these tires should offset the cost of the tires and corresponding wheels within a reasonable payback
period. By itself, this should result in the widespread use of these tires by commercial
heavy-duty fleets.
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