In previous issues of Alternative Fuels

in Trucking, we reported on several

demonstration projects that used different alternative fuels in actual trucking operations. We now have data

highlights from the first completed

project, a demonstration comparing

ethanol with diesel in three snowplow

and road maintenance trucks in

Hennepin County, Minnesota (see

Alternative Fuels in Trucking, Volume

2, Number 4).

From November 1993 to October

1996, Hennepin County (which

includes the city of Minneapolis) fieldtested two snowplow and road maintenance trucks fueled with E95 (a

95%/5% blend of ethanol and gasoline). The test was designed to compare ethanol truck performance with

diesel truck performance in all weather

environments. The U.S. Department of

Energy (DOE) funded the project

through the National Renewable

Energy Laboratory (NREL). The ATA

Foundation's Trucking Research

Institute (TRI) managed the project.

Ethanol, an alcohol produced from

grain, has been used as a fuel additive

to gasoline for years. It is a worthy

prospect as an alternative fuel for several reasons. It is produced in the

United States, and it is renewable

because its feedstock crops can be

regrown and harvested annually (more

often in some cases). It also has more

desirable emissions characteristics than

conventional automotive fuels.

However, it has rarely been tested in

heavy-duty vehicles in high percentage

blends.

The Hennepin County road test used

three trucks in all. Two were fueled

with E95 and one diesel-fueled truck

was used as a control vehicle. Engine

modifications were needed for the

engine control module, fuel system,

glow plugs, by-pass air system, and

compression ratio. No special safety

precautions were necessary. 

During the winter, the trucks ran in 8-

hour shifts plowing snow off the urban

and suburban roads of Hennepin

County and hauling the snow to a

dump site. The rest of the year, the

three trucks were used for paving and

road maintenance. On a weekly basis

Volume 6, Number 3

Ethanol Fuel Demonstration in

Hennepin County, Minnesota

This snowplow in Hennepin County, Minnesota, runs on E95.

Photo courtesy of Ag Processing, Inc./PIX04978

INSIDE THIS ISSUE

EPA Revises Tampering Policy for Conversions.................................3

Evolution of the ATA's Alternative Fuels Task Force...............................4

John Deere Introduces Two New Natural Gas Engines............................6

Alternative Fuel Taxes Reduced in Taxpayer Relief Act of 1997..............7
throughout the project, drivers rated

the trucks on operational characteristics and documented fuel use, oil use,

and maintenance frequencies. These

data were collected and stored in the

Alternative Fuels Data Center at

NREL. 

Researchers from West Virginia

University ran the trucks through a

series of tests, using a dynamometer to

simulate general truck driving patterns

and test the emissions. The researchers

found that the ethanol trucks produced

fewer oxides of nitrogen (NOx) emissions and particulates, but more carbon

monoxide (CO) and hydrocarbons (see

Table 1).

The Hennepin County drivers reported

that the E95 trucks performed nearly

as well as the diesel truck, producing

about the same quality of work in the

same amount of time. Exceptions they

noted resulted from the primary and

secondary fuel filters in the E95

trucks, which clogged frequently,

causing the trucks to starve for fuel,

hesitate, stall, and sometimes be harder

to start. Fuel economy was also a

concern. The ethanol trucks used

about twice as much fuel as the diesel

truck based on the volume of fuel per

mile (#2 diesel contains about 1.5

times as much energy as E95).

Maintenance and repair costs for the

E95 trucks were consistently higher

than those for the diesel control.

Additional costs are attributed mainly

to the fuel system. Frequent fuel filter

replacement was the biggest expense

and fuel pump replacement on both

E95 trucks added significantly to the

total costs. Although these were the

most expensive maintenance and

repair items in the demonstration,

commercialization would surely bring

refinement and reduced prices in this

area.

A complete final report on the project

will soon be available from NREL.

2 Alternative Fuels In Trucking—Volume 6, Number 3

Table 1. Emissions Comparisons Between E95 and Diesel

CO 7.4 6.4 9.0 28.7 4.3 5.2

NO2 12.3 11.6 14.8 11.6 13.2 13.2

PM 0.30 0.37 0.45 0.56 0.83 0.8

HC 4.98 3.94 5.69 7.12 1.35 1.44

1994 1995 1994 1995 1994 1995

E95 E95 Diesel
Alternative Fuels In Trucking—Volume 6, Number 3 3

EPA Revises Tampering Policy

for Alternative Fuel Conversions

On September 4, 1997, the U.S.

Environmental Protection Agency

(EPA) issued its Addendum to the

Mobile Source Enforcement

Memorandum 1A (Memo 1A).

Memo 1A was originally released in

1974 to clarify the EPA's policy on

the tampering prohibition contained

in Section 203(a) of the Clean Air

Act. The September 1997 addendum

revises and clarifies the tampering

policy directed at vehicles and

engines converted to use alternative

fuels. The regulation in

Memorandum 1A states that if manufacturers alter a vehicle or engine in

any way, they must have a "reasonable basis" to believe the modification will not adversely affect emissions performance or the EPA may

consider it tampering. The tampering

policy defines a "reasonable basis" as

either successfully passing emissions

testing under the 40 CFR 86 regulations, or obtaining a representation

that a reasonable basis exists from a

federal, state, or local environmental

control agency. Historically, when

doing aftermarket conversions,

mechanics have used the second definition and often follow test procedures established by the states of

California and Colorado.

In 1996, the National Renewable

Energy Laboratory published a study

that showed that vehicles converted

under the provisions of Memo 1A

(prior to the addendum) exhibited

higher emissions of some constituents when tested on the alternative fuel compared to reformulated

gasoline. The EPA subsequently

reviewed this information, along with

other available data, and determined

that vehicles modified to run on

alternative fuels may be exceeding

one or more of the applicable federal

emissions standards.

After review, the EPA issued the

Addendum to Memo 1A with new

conversion guidelines for manufacturers and installers. The revised

policy states that the EPA will no

longer accept representations based

on pre-1994 California certification

procedures, or procedures under

Colorado's Regulation Number 14 as

providing a "reasonable basis."

Furthermore, they limit the criteria

for a "reasonable basis" to one of

these three options:

1. Manufacturers must obtain a federal certificate under CFR Part 86 

showing that they comply with the

standards.

2. For California vehicles, manufacturers and installers must have a 

retrofit system certification under 

the "California Certification and 

Installation Procedures for 

Alternative Fuel Retrofit Systems 

for Motor Vehicles Certified for 

1994 and Subsequent Model 

Years."

3. Until December 31, 1998, they 

must perform specific emissions 

tests as defined in the addendum.

The installers must keep the records

of each converted vehicle or engine,

including the vehicle identification

number, make and year of vehicle or

engine, the installer's name, the date

of installation, and a copy of the

manufacturer's or marketer's representation.

The EPA believes that aftermarket

conversions of vehicles and engines

will meet federal emissions standards

The Environmental

Protection Agency recently

released a colorful, comprehensive, and easy-to-follow

reference guide to emissions

standards for heavy-duty and

nonroad engines. The guide,

which is available free of

charge in two formats—a folded brochure and a poster—

can be obtained from:

Jennifer Barker

U.S. EPA

Office of Mobile Sources

2565 Plymouth Road

Ann Arbor, MI 48105

(313) 668-4510

The guide can also be found

on the World Wide Web at

http://www.epa.gov

/OMSWWW/nonroad.htm

EPA Releases

Definitive Reference

Guide to Emissions

Standards
4 Alternative Fuels In Trucking—Volume 6, Number 3

Do you know what the ATA

Foundation's Alternative Fuels Task

Force is, who its members are, and

what it does? As the Task Force

marks its eighth year, we would like

to review its history and describe its

current work.

Those new to the trucking industry

may not have vivid memories of the

gasoline crises that bogged down our

country in the 1970s. Back then,

political instabilities in the Middle

East triggered a massive oil embargo

that created historic disruptions in

U.S. transportation fuel supplies. The

era became known for its "gas lines,"

expensive fuel, and attendant inconveniences. At the time, the United

States imported about 30% of its

oil—today, we import about 50%. 

The fuel supply disruptions of the

1970s spawned a national resolve to

explore energy and fuel options and

to move the country toward energy

independence and develop alternative

fuels and products not tied to

petroleum resources. However,

lower oil prices and increased economic prosperity soon allowed the

specter of the nation's energy vulnerability to fade. 

By the late 1980s, national concern

had turned to environmental and

health issues and modifying the

Clean Air Act to improve air quality

more rapidly. Gaseous emissions

Evolution of the ATA's

Alternative Fuels Task Force

only if they comply with 40 CFR

Parts 86 or 88. However, because of

the time and money it takes to set up

and perform the necessary test procedures, some may not be able to meet

these standards in the short term.

Option 3, mentioned above, allows

some leeway in getting vehicles and

engines ready to conform to the new

EPA standards. After December 31,

1998, however, all manufacturers,

marketers, and installers must use

equipment that conforms to either

option 1 or 2 covered by the tampering policy of the new Addendum.

The EPA plans a thorough review of

the policy soon to see if additional

regulatory changes are needed for

other types of vehicle or engine modifications, parts, or systems.

Questions regarding this policy

should be directed to the Mobile

Source Enforcement Branch at

(202) 564-2255. The full text of

Addendum to Memorandum 1A is

available on the EPA's web page at 

http://es.inel.gov/oeca/ore/aed/comp/

jcomp. It was also published in the

Federal Register on October 27,

1997 (Volume 62, Number 207). 

The Department of Energy and the

National Renewable Energy

Laboratory have published A Guide

to the Emissions Certification

Procedures for Aftermarket

Conversions, which provides a "user

friendly" explanation of the certification procedures required by the EPA

and the California Air Resources

Board. The guide is available

through the National Alternative

Fuels Hotline (1-800-423-1DOE),

and on the World Wide Web at

http://www.afdc.doe.gov (click on

What’s New).

NT

Y A

U

E OF ENERG

DEPARTM

E

N ITED STAT S OFA ERIC M

A Guide to the

Emissions

Certification

Procedures

for Alternative Fuel

Aftermarket Conversions

This guide leads the reader through

the procedures for emissions certifying aftermarket conversions to alternative fuels.
Alternative Fuels In Trucking—Volume 6, Number 3 5 

from cars, trucks, and buses received

critical attention. Alternative fuels

and systems again presented a potential solution—they could not only be

produced domestically, but they produced fewer toxic emissions. This

fact renewed interest in alternative

fuel research. By the late 1980s, the

alcohol fuels, especially methanol,

were being touted as the best alternative fuels, chiefly because of

widespread availability and ease of

distribution.

The trucking industry, being totally

dependent on diesel and gasoline for

its livelihood, was keenly interested

in learning all it could about all types

of alternative fuels—alcohols, natural

gas, biodiesel, and others—before

encouraging a switch from conventional fuels. 

Motor carriers, engine manufacturers,

parts suppliers, and maintenance

crews also needed to know what

would be involved in developing

alternative fuel products. Everyone

connected with the industry needed

information about the fuels themselves—availability, cost, safety, and

infrastructure requirements.

To meet the information needs, the

ATA Foundation, the research affiliate of the American Trucking

Association, commissioned Battelle

Memorial Institute to conduct a study

and convened the Alternative Fuels

Task Force. The Task Force's purpose was twofold: first, to provide

Battelle the necessary industry input

and access to help with the study;

and second, to act as an alternative

fuels information conduit from the

Foundation to industry motor carriers

and suppliers.

The Battelle study, Effects of

Alternative Fuels on the U.S.

Trucking Industry, was published in

April 1991 and the Foundation's role

in alternative fuels research grew.

The Task Force expanded both in

membership and scope. The ATA

Foundation, through its Trucking

Research Institute (TRI), partnered

with DOE's National Renewable

Energy Laboratory (NREL) to pursue

a testing demonstration program

using several different alternative

fuels in various trucking operations.

As the information conduit role

expanded to include federal, state,

and local governments, Task Force

membership grew. And as the scope

of needed information grew, representatives from the associated industries joined the group. New members

included representatives from industries such as natural gas, alcohol

fuels, biodiesel, and cryogenic tank

and compressed gas cylinder suppliers and distributors.

With this growth and expanded

scope, it became appropriate to create

subcommittees to deal with technical

issues. Although the Task Force

focuses on informing industry members about any alternative fuels

developments that might affect them,

the Manufacturers' Technical

Subcommittee plays a specific role in

advancing the production and use of

natural gas in heavy-duty vehicles. 

Truck and engine manufacturers have

expressed strong interest in liquefied

natural gas (LNG) because of its low

cost (competitive with petroleum

fuels) even though the physical properties of this alternative fuel require

significant infrastructure investment

and vehicle systems modifications.

The Manufacturer's Technical

Subcommittee, in partnership with

the Society of Automotive Engineers

(SAE), addressed these issues with a

Recommended Practice to guide the

industry in producing LNG trucks.

The guide helps industry members to

meet the highest safety standards and

comply with appropriate regulations.

The subcommittee also works with

regulatory agencies, particularly at

the state and local level, to help them

in formulating regulations that ensure

safety and compliance without an

undue burden. The LNG work culminated in January 1997 with the publication of SAEJ2343 ("Recommended

Practices for LNG-Powered HeavyDuty Trucks”). The subcommittee is

currently working with the Gas

Research Institute to prepare similar

guidance to the industry for medium

heavy-duty trucks fueled with compressed natural gas.

The ATA Foundation's Alternative

Fuels Task Force has become a large

organization with a membership that

reflects the breadth and complexity

of the industry. The members share

the kind of information that will lead

them to intelligent decisions on how,

when, where, and why to use alternative fuel vehicles. Alternative fuel

decisions are highly complex, and

members gain valuable insights from

each other because of their varied

backgrounds. Anyone interested in

obtaining further information on the

Task Force or the Manufacturers'

Technical Subcommittee may call

Bill Peerenboom at the Trucking

Research Institute, (703) 838-1863,

or contact the ATA Foundation by email at ata_found@aol.com.
6 Alternative Fuels In Trucking—Volume 6, Number 3

At the June 1997 National Clean

Cities Stakeholders' Conference and

Expo in Long Beach, California, the

John Deere Company presented

information on its two natural gas

engines. The engines are a major step

toward increasing the trucking industry's use of alternative fuels. John

Deere started manufacturing natural

gas engines in 1994 with the 6081H

PowerTech 8.1L. In early 1998, the

company will introduce its 6068H

PowerTech 6.8L engine. 

Because performance is a major concern for the trucking industry, John

Deere designed the engines with

enough power and torque to carry

heavy loads and climb hills like conventional diesels. Additionally, both

engines already meet the U.S.

Environmental Protection Agency's

1998 emissions standards for heavyduty vehicles. The PowerTech 6.8L

and the 8.1L engines also promise

fewer emissions and quieter operation than conventional diesel fuel

engines. The individual wet cylinder

liners of the 6.8L model act to dissipate heat from the engine quickly.

And, because the liners are individual, the engine can be rebuilt, extending engine life.

The PowerTech 8.1L engine is the

more powerful of the two, with 250

horsepower at 2200 rpm (see Table 2

for technical specifications). Both

engines feature turbo-charged aspiration, air-to-air charge-air cooling, and

a spark-ignited combustion system.

They have a lean-burn, closed-loop

adaptive learn technology and electronically controlled emissions management systems. Figures 1 and 2

illustrate the performance curve for

both engines. The 6.8L model is

smaller and lighter, with a low idle

speed of 650 rpm. It also features

lean-burn, closed-loop adaptive learn

technology and an electronically controlled emissions management system. These latter features give both

engines more constant performance,

emissions control, and the potential

for better fuel economy than a conventional diesel engine. 

The Deere 6068H PowerTech 8.1L

engine is currently operating in

school buses in northern California.

The 8.1L is also available for trucks

and the manufacturer recommends

this engine for centrally fueled fleets

that make urban deliveries. The

PowerTech 6.8L engine will become

available in early 1998 and will also

be used in school buses and heavyduty truck markets.

John Deere Introduces Two New

Natural Gas Engines

6081H 6068H

PowerTech 8.1L PowerTech 6.8L

Horsepower 250@ 2200 rpm 225 @ 2400 rpm

Length 45.5 in. 43.5 in.

Width 32.0 in. 32.2 in.

Height 48.1 in. 32.9 in.

Dry Weight 1470 lb 1290 lb

Compression Ratio 10:1 11:1

Peak Torque 800 lb-ft @ 1350 rpm 640 lb-ft @ 1500 rpm

8.1 L CNG (6081 H) PowerTech engine Table 2. Technical Specifications of John Deere

Natural Gas Engines
Alternative Fuels In Trucking — Volume 6, Number 3 7

Alternative Fuel Taxes Reduced

in Taxpayer Relief Act of 1997

On August 5, 1997, President Clinton

signed the "Taxpayer Relief Act of

1997." Several provisions in the Act

directly affect the trucking industry.

Beginning October 1, 1997, the tax

rate for liquefied petroleum gas or

propane was lowered to 13.6 cents

per gallon (instead of being taxed at

the same rate as gasoline, 18.4 cents

per gallon). The tax rate for liquefied natural gas has also been

reduced from 18.4 cents to 11.9 cents

per gallon. On a Btu basis, the

reductions make the tax rate on these

alternative fuels the same as the tax

on gasoline. Because LNG competes

principally with diesel, its tax rate is

now less than that for diesel fuel on a

Btu basis. The rate for methanol produced from natural gas has also been

lowered from 11.3 cents to 9.15 cents

per gallon. 

Beyond these changes, several other

stipulations from the Act will directly

and indirectly affect the trucking

industry. The Act designates that 4.3

cents of the tax will go into the

Highway Trust Fund, split between

the Highway Account (3.45 cents)

and the Mass Transit Account (0.85

cents). No fuel tax money will go to

support Amtrak; however, the organization will receive income tax

refunds to be enacted through future

authorizing legislation. Also, from

October 1, 1997, through March 31,

2005, the 0.1 cent-per-gallon Leaking

Underground Storage Tank tax will

be reinstated, and starting July 1,

1998, kerosene will be subjected to

the same tax-or-dye rules as diesel

fuel.

640 lb-ft

(868 Nm)

496 lb-ft

(672 Nm)

225 hp

(168kW)

Intermittent torque

Intermittent power

Fuel consumption

280

(209)

200

(149)

120

(90)

40

(60)

Break power -hp(kW)

560

(759)

240

(325)

400

(542)

0.36

(218)

0.32

(194)

Torque lb-ft(Nm)

Engine speed - rpm

Fuel - lb/hp-hr(kWh)

1000 1200 1400 1600 1800 2000 2200 2400

800 lb-ft

(1085 Nm)

597 lb-ft

(809 Nm)

250 hp

(186 kW)

Intermittent torque

Intermittent power

Fuel consumption

300

(224)

250

(186)

200

(149)

150

(112)

100

(75)

Break power -hp(kW)

750

(1016)

800

(1084)

650

(880)

600

(813)

550

(745)

700

(949)

0.36

(218)

0.32

(194)

0.28

(170)

Torque lb-ft(Nm)

Engine speed - rpm

Fuel - lb/hp-hr(kWh)

1000 1200 1400 1600 1800 2000 2200 2400

Figure 1.

PowerTech natural gas 6.8L engine performance curve.

Figure 2. 

PowerTech natural gas 8.1L engine performance curve.
Volume 6, Number 3

René Howard, Editor

Lisa Shertz, Graphic Designer

Alternative Fuels in Trucking is published quarterly

by the National Renewable Energy Laboratory

(NREL), a U.S. Department of Energy (DOE) 

national laboratory. The newsletter is written by 

the American Trucking Association Foundation’s

(ATAF’s) Trucking Research Institute.

The aim of Alternative Fuels in Trucking is to

inform fleet owners and operators, equipment suppliers, government officials, and other interested parties

about important developments in the use of alternative

fuels in heavy-duty trucks. Suggestions and comments

are welcome and may be directed to the National

Alternative Fuels Hotline at 800-423-1DOE. Views

expressed by guest authors are their own, and not

those of ATAF, DOE, or NREL.

NREL/BR-540-23718

March 1998

Printed with a renewable-source ink on paper

containing at least 50% wastepaper, including

20% postconsumer waste

UNITED S AT

FO SET

MA

ER

CI A

• DEPAR MT

FOTNE

NE ERGY •

U.S. Department of Energy

Office of Energy Efficiency and Renewable Energy

Office of Transportation Technologies

How to Reach Us

• The AFDC World Wide Web 

address is 

http://www.afdc.doe.gov

• The Alternative Fuels in

Trucking newsletter is available

on the WWW at http://www.

afdc.doe.gov/1/trknews It is

available on-line 2 or 3 weeks

before the newsletter is mailed.

To speak to a human

being, call the

National Alternative

Fuels Hotline at 

800-423-1DOE.