Table 2.19

Weight Class Distribution for Light-Duty Trucks,
Model Years 1975 through 1978

aData based on manufacturers' sales estimates.

Source: J. D. Murrell, Light Duty Automotive Fuel Economy Trends Through 1978, SAE Paper 780036.

Table 2,20

Sales-Weighted Fuel Economy for Light-Duty Trucks,
Model Years 1975 through 1978

Source:

EPA urban/highway mpg.

J. D. Murrell, Light Duty Automotive Fuel
Economy Trends Through 1978, SAE Paper 780036.

THE USE OF LIGHT TRUCKS AND VANS IS GAINING SUBSTANTIAL POPULARITY. PRESENTED IN THE TABLE BELOW ARE THE ENERGY INTENSITIES TO BE EXPECTED OF THESE VEHICLES WHEN USED FOR PERSONAL TRANSPORTATION.

All values are calculated on a route-mile basis.
To convert these to a great-circle-mile basis
they should be multiplied by the intercity auto-
mobile circuity ratio of 1.212. No circuity data
for urban uses are available.

Including driver.

Source: A. B. Rose, The Energy Intensity of 1977
Model Year Automobiles and Light Duty
Trucks, Oak Ridge National Laboratory,
Oak Ridge, Tenn., October 1978,
unpublished.

THE LARGE INTERCITY TRUCKS, WITH GROSS VEHICLE WEIGHTS OVER 65,000 LB,

SHOULD BE SINGLED OUT BECAUSE THEY ACCOUNT FOR THE OVERWHELMING MAJORITY
OF ALL TRUCK CARGO TON-MILES. THEIR ENERGY INTENSITY UNDER ACTUAL
OPERATING CONDITIONS IS APPROXIMATELY 2500 BTU/ROUTE-TON-MILE. HOWEVER
MANY OF THE NEW TRUCKS ENTERING THE FLEET ARE EQUIPPED WITH A SERIES OF
ENERGY-SAVING OPTIONS WHICH WILL DECREASE THIS VALUE SUBSTANTIALLY IN
THE NEAR FUTURE. THE SAVINGS POTENTIAL FROM THESE OPTIONS, OUTLINED IN
TABLE 2.22, ARE BASED ON THE ACTUAL OPERATING EXPERIENCE FROM THE TRUCKS

IS

BUSES SERVE A LARGE VARIETY OF TRANSPORTATION NEEDS. THE INTERCITY BUS

IS THE MOST ENERGY EFFICIENT OF THE PUBLIC PASSENGER TRANSPORTATION MODES.

b.

"Large system-to-system variations exist within this category.

For purposes

These values are calculated on a route-mile basis.
of intermodal comparisons they should be multiplied by a circuity.
factor of 1.114 to convert them to a great-circle-mile basis.

Sources:

passenger-mile.

American Bus Association, America's Number 1 Passenger
Transportation Service, Washington, D.C., 1977,

supplemented with private communications with the
American Bus Association; American Public Transit
Association, Transit Fact Book, '76-'77 ed.,
Washington, D.C., June 1977.

SINCE THE NUMBER OF PASSENGER-MILES TRAVELED ON BUS TRANSIT SYSTEMS IS NOT KNOWN, ONE MUST CALCULATE ALL PASSENGER ENERGY INTENSITIES PARAMETRICALLY BY ASSUMING A TRIP LENGTH.

*Calculated given that the energy intensity = total energy used (number of passengers x trip length). The mean trip length in 1971 was 4.38 miles. Base data for other years: 1974, 45.11 x 1012 Btu, 4057.1 x 106 trips; 1975, 51.51 x 1012 Btu, 4150.9 x 106 trips; 1976, 54.72 x 1012 Btu, 4221.9 x 106 trips.

Source:

A. B. Rose, The Energy Intensity and Related Parameters of
Selected Passenger Transportation Modes, ORNL-5506, Oak Ridge,
Tenn., 1979.