A

lmost 50% of the petroleum

consumed in the United

States is imported. By the

year 2000, 73% of total petroleum

demand will be imported, making

America vulnerable to a cutoff in our

energy lifeline. Transportation, which

is 98% dependent on petroleum, uses

two-thirds of the oil consumed in the

United States. If we instead used

American-produced natural gas to

power our vehicles, we could become

energy independent.

Natural gas could also solve some

of our toughest environmental problems. Gasoline- and diesel-fueled

cars, trucks, and buses produce half

of all air pollution in the United

States. Natural gas would cut emissions to zero.

Congress has recognized the

opportunity and enacted legislation 

to provide incentives for or mandate

the production of alternative fuel

vehicles (AFVs).

In 1988, Congress imposed

Corporate Average Fuel Economy

standards for vehicles and imposed

significant fines on those who fail to

meet them. In 1990, the Clean Air

Act Amendments tightened emission

controls on a variety of air pollutants,

and created a clean fuels fleet program. In 1992, the Energy Policy Act

(EPAct) was passed to respond to the

energy security concerns raised by

the Gulf War. It contains several

mandates and incentives to increase

the use of AFVs.

But we have just scratched the

surface of the use of natural gas 

vehicles (NGVs). There is still much

more to be done. That is why Speaker

Gingrich created the Congressional

Task Force on Natural Gas Vehicles

and appointed me chairman.

We found that there are more than

1,100 natural gas fueling stations in

the United States and nearly 50,000

NGVs on the road in the United

States today. That number could 

dramatically increase, particularly 

if more trucks are fueled by 

natural gas.

The natural gas option is so good

because it is potentially cheaper than

gasoline. At today's prices, natural

gas is approximately one-third as

expensive as regular unleaded gasoline and and one-half the price of

diesel.

Manufacturers are stepping up to

meet the demand. In the 1996 model

year, a number of factory-built NGVs

became available from Detroit.

This opportunity demands a serious response by Congress. Prior 

legislation has tried to increase 

general awareness of and created a

limited fleet market for NGVs. But

current law and regulations have not

provided the impetus for their mass

production, which is the reason I 

am trying to redirect the role of the 

federal government. We now understand the barriers to incentives for

using natural gas. To remove those

barriers we have formulated the

Natural Gas Vehicle Incentives Act 

of 1996.

First, this legislation will establish

an emission reduction credit program

for NGVs and a fueling infrastructure. Next, it will establish a tax

credit for NGVs and fueling stations

used for business purposes (specifically targeting fleet operators). In

addition, the bill provides shorter

depreciation recovery periods for

Volume 5, Number 3

Natural Gas Vehicles: Wave of the Future

by Congressman Joe Barton

INSIDE THIS ISSUE

The Learning Curve in LNG

Alternative Fuel Trucks.......3

Christine Ervin Speaks at

Natural Gas Vehicle

Conference...........................5
NGVs and refueling property. Pending

the enactment of these incentives, our

legislation proposes to eliminate the

private fleet mandates imposed by

EPAct and will in 1999 sunset the

state fleet mandates and fuel provider

mandates contained in EPAct.

The bill also corrects the tax rate

for liquefied natural gas (LNG), the

clean fuel alternative to diesel.

Because LNG is a liquid form of

compressed natural gas, it provides

increased storage needed for long

hauls. However, until the tax rate is

corrected, the market for LNG will

cease to exist except in tax-exempt

public fleets.

This legislation help decrease the

transportation sector's dependence on

imported oil, enhance our air quality,

increase domestic economic activity,

and minimize the cost to taxpayers.

Incentives to the private sector are

the most efficient and effective 

means to produce long-term reductions in motor vehicle emissions and

oil imports.

We have witnessed staggering

technological advancements during

the past 100 years. The changes in

the next 100 years will be even more

dramatic, and I believe a dramatic

increase in natural gas-powered cars

and trucks will be one of those

changes.

Heavy-Duty Truck Project

in the Spotlight

Airgas Houston-Penske Truck

Leasing

Airgas, Inc., is a premier 

distributor of industrial, medical, 

and specialty gases in North A m e r i c a.

Its operations include a vast network

of more than 500 distribution locations throughout the continent.

Because of the company's daily

involvement with these products, it

investigated the use of natural gas as

an alternative fuel for its fleet. As is

always the case with moving to a different technology, Airgas conducted

research to decide which of the 

several alternative fuels best suited

their needs, and which location

would prove the most advantageous.

Inquiries led Airgas to choose liquefied natural gas (LNG) as the fuel,

and Houston as the location, because

that city has the beginnings of an

LNG infrastructure. Airgas also

wanted to ensure that its involvement

with LNG was conducted so as to

maximize its learning experience

without losing productivity. To

achieve this, Airgas turned to Penske

Truck Leasing, one of the nation's

major full service truck leasing companies, whose services would include

full maintenance and repair for the

LNG-powered trucks. 

Penske's servicing of the LNGpowered trucks would yield valuable

data on their operations in day-to-day

revenue service, and could be easily

matched for control purposes with

identical conventionally powered

trucks in nearly identical service.

Such a project appealed to the

Trucking Research Institute, which

has been engaged for several years

with DOE's National Renewable

Energy Laboratory (NREL) in facilitating heavy-duty truck alternative

fuel projects in revenue service. As 

a result, NREL agreed to sponsor the

project, in return for receiving data

from the operations of the trucks. 

Particularly appealing was the

fact that these straight trucks were

the first produced “on line” by

Freightliner. Detroit Diesel's S50G

engine powers the trucks, for which

the chassis chosen was Freightliner's

FLD-112. Two LNG-powered trucks

were produced, and delivered along

with a new diesel-powered vehicle 

to serve as a control for the project.

The fuel storage and delivery system 

produced by Minnesota Valley Engineering was installed at Freightliner

as part of the original equipment

manufacturer (OEM) production 

process. That system consists of two,

90-gallon tanks, which provide 

adequate capacity for the trucks as

they deliver industrial gases in

greater Houston. The routes require

the trucks to make 15 to 20 stops per

day, and each vehicle logs about

40,000 miles each year. Each day's

run is about refueling takes place

weekly, and is done at one of the

LNG fueling facilities operated by

the Houston Metro, whose fuel is

99.5% pure methane supplied by

Praxair's LNG plant at Willis, Texas.

Since the trucks entered service in

May 1996, there have been relatively

few growing pains. Drivers have

expressed pleasure at the quiet and

smooth ride with their spark-ignited,

300- horsepower engines. They also

state that the trucks are clean, and

produce far lower levels of fumes

during the stop-and-start driving conditions that characterize their routes. 
Creating an alternatively fueled

commercial truck means finding a

fuel and engine that can compete

with the most efficient fuel and

engine system on earth, the diesel.

We are discussing commercial vehicles, so the competition must be on

all fronts: economics, performance,

reliability, availability and, of course,

safety. Once each of these competitive factors comes into play, it brings

with it a whole series of issues. The

simplest, but certainly not the only,

economic factor is base cost of the

fuel itself, measured not only on a

volume basis, but also on a cost per

unit of energy, or distance. In the

case of LNG, there really is competitiveness with diesel at the level of

raw product cost, but one must be

sure to define the product. There are

various kinds of LNG; the most 

plentiful, called “peak shaving,” is

reasonably available and cost competitive. There is, however, the issue

of whether that kind of LNG is suitable to power a truck, as opposed to

fuel a furnace. Because LNG is a

cryogenic version of natural gas—

a chemical mixture as opposed to 

a chemical compound—any given

sample can, and usually does, vary 

in its chemical makeup. Therefore,

cost competitiveness must be 

tempered with recognition of the 

particular LNG quality, expressed 

as some sort of specification. 

The designers and builders of an

engine need to decide which fuel will

best suit the needs of that engine.

After all, if the fuel doesn't work, for

whatever the reason, the engine manufacturer will get the call. So, for

simplicity, we will use the convention LNG*, understanding that (1)

the star (*) implies the LNG discussed

meets the quality and content standards of engine manufacturers; and

(2) because of differences in design,

there may be some minor differences

in the specification. 

Because of the cryogenic nature

of LNG (starred or not), its composition is always changing to some

degree, because it is always “boiling.”

While it boils, the individual components (methane, ethane, propane,

nitrogen, etc.) leave the liquid state

and becoming vapor one at a time,

each as it reaches its own boiling

point. Over time, the fuel undergoes

some chemical change—it “weathers.” The rate at which weathering

occurs is a function of many things,

among them tank configuration (size,

shape, and construction), and rate of

use. LNG* aboard a vehicle being

driven is being burned, and it meets

engine specifications, so the weathering effect is not an issue.

More importantly, users of conventionally fueled trucks are not

accustomed to worrying about what

they buy, so with alternative fuels,

the same condition must apply.

LNG* has to be composed of whatever component percentages engine

manufacturers specify. These manufacturers have learned the effects of

greater or lesser concentrations of

methane, and of the several other 

elements and compounds that constitute “impurities.” The user must

understand and be aware of the 

manufacturer's specification be satisfied that the fuel supply meets the

specification; in other words, “trust

but verify.”

The next differences that users of

commercially operated LNG* trucks 

The Learning Curve in LNG Alternative Fuel

Trucks

by Bill Peerenboom, Vice President, Trucking Research Institute
must understand relate to fuel storage

and delivery. LNG's* competitive

advantage as a transportation fuel is,

in part, due to its reasonably comparable energy density, which gives an

LNG* truck competitive, although

not equal, range to its diesel counterpart. Fortunately, truck fuel tanks are

generally of simple geometric shapes,

and numbers of similarly shaped

cryogenic tanks are manufactured 

for other uses. These can readily be

fitted to a tractor chassis with little or

no difficulty. These tanks, however,

are far more complex than their

diesel counterparts; they are actually

very sophisticated “thermos bottles.”

Additionally, because the engine

burns the fuel as a vapor, and the

tank stores it as a liquid, the fueling

system itself is more complex than its

diesel competitor, because the system

must be able to convert the liquid to

a vapor and deliver it to the engine 

at a specific pressure. In most trucks,

this is done without benefit of a

pump; the system is designed to rely

on the application of differential

pressures and temperatures through

the use of regulators, heat exchangers, and valves. The necessary design

and component configurations are

arrived and through the concentrated

cooperative efforts of truck chassis

OEMs, engine manufacturers, and

fuel tank suppliers.

Once the engine-fuel system

design physics are determined, the

truck has acquired a characteristic 

not shared by the diesel truck—it

must be “compatible” with the capabilities that refueling sites must meet.

Each refueling site must be able to

deliver LNG* at a particular pressure

and temperature to vehicles being

fueled. 

Pressure and temperature? Yes,

because LNG, like all cryogenic 

fluids, changes density (mass per 

unit volume) as a function of both,

and for each pressure there is a particular temperature at which the fluid

is most heavily concentrated when

the fluid is said to be “saturated,” or

“conditioned.”

Why should the operator care

about such an esoteric concept?

Simply because a gallon of saturated

fuel contains more energy than a gallon of unsaturated fuel, and inattention to this fact can cause the operation to literally run out of gas. So the

operator needs to know that his fuel

supplier is providing and dispensing

saturated or conditioned LNG*, or

there could be trouble.

Fuel storage—either on-board or

for dispensing—must also account

for the fact that over time, LNG* in a

tank boils; because the tank is a

closed-pressure vessel, its pressure

will rise. The remedy is to use the 

fuel—either send it to the engine, or

dispense it to a vehicle. The operative caveat is “use it or lose it,”

because each tank has a relief valve

that will lift when the tank pressure

increases to its set point. This is

called “venting,” and is critical to the

economics of LNG* because fuel that

vents is money lost.

Finally, in addition to these economic and physical challenges, 

building and operating LNG*-

powered trucks must be done safely

and legally. That means designs, 

construction, operation, and maintenance must be consistent with the

unique safety requirements that relate

to LNG*, and that trucks must comply

with federal, state, and local laws,

regulations, and industry practices set

down for them.

All these complications may seem

like serious barriers to competition.

They are, but the good news is that

the necessary steps to break them

down have been, or are being, taken. 
Christine Ervin Speaks at Natural Gas Vehicle

Conference

Extracts from the Remarks of Christine Ervin, Assisstant

Secretary of Energy Efficiency and Renewable Energy, Keynote

Speech to the 14th National Natural Gas Vehicle Conference,

Dallas, Texas, September 17, 1996

Many of you have seen the cover

story in last April's issue of Atlantic

Monthly, written by my principal

deputy, Joe Romm, and deputy secretary Charles Curtis. It starts by asking us to “. . . imagine a world in

which the Persian Gulf controlled

two-thirds of the world's oil for

export with $200 billion a year in oil

revenues streaming into that unstable

and politically troubled region, and

America importing nearly 60 percent

of its oil, resulting in a 

$100 billion year outflow that undermined efforts to reduce our trade

deficit.”

That's a scenario out of the 1970s

which can never happen again, right?

No, that's the base case for 10 years

from now from the independent

Energy Information Administration.

Now, as tensions continue in the

Persian Gulf, we see articles like the

one in last weekend's Washington 

Post headline: “If we kicked the oil 

habit, Saddam wouldn't menace us.”

This concern about oil dependency is shared by experts from every

point on the political spectrum. Don

Hodel, Secretary of Energy under

Ronald Reagan, said that we are

“sleepwalking into a disaster,” and

predicts a major oil crisis within the

next decade. Irwin Stelzer, of the

American Enterprise Institute, says

that the next oil shock “will make

those of the 1970s seem trivial by

comparison.” Robert Dole said in a

speech last year that “the second

inescapable reality of the post-20th

century world is that the security of

the world's oil and gas supplies will

remain a vital national interest of the

United States and of other industrial

powers.”

Clearly, our ever-growing dependence on imported oil, now at a

record high, is a major problem looking for a solution. An important part

of that solution is the development 

of a market for alternative fuels and

more efficient vehicles that can use 

a variety of fuels. Only then can we

stop exporting more than $1 billion

dollars out of this country each and

every week and use it here at home

to strengthen our economy. Part of

that solution is to encourage more

efficient production of oil here at
home and from more reliable sources

around the world—both strategies are

being pursued by the Clinton

Administration.

What about air pollution? One of

the greatest rediscoveries this past

two years is that the American public

demands a clean environment. In

unambiguous numbers they have 

said that compromises on clean air

and water are unacceptable. Here

again, natural gas and other clean

fuels play a vital role. The greatest

remaining source of air emissions in

many urban cities today is not power

plants or industrial sites . . . but cars,

trucks, and buses. We are spending

over $50 billion each year on health

care related to air pollution—pollution and health care costs that could

be reduced with a balanced clean

transportation strategy.

I speak a lot about natural gas and

other alternative fuels. Why?

Because only recently each fuel

advocacy group would come into 

my office complaining about the

preferential treatment elsewhere.

After a while I couldn't figure out

whether or not we were held captive

by the electrics, the ethanol groups,

or the natural gas lobbies. It was

clear that the alternative fuels industries werecompeting against each

other for less than half of 1% of the 

market. That kind of competition

doesn't make much sense. So, I'm

very glad to see a new sense of

strategic cooperation across the

groups. There's plenty of room for

everyone at the fuel pump.

Of course we're all too familiar

with the classic chicken and egg

dilemma we face: how to simultaneously strengthen supply and demand.

Part of the federal role is to at least

get the chicken and egg in the same

basket. Which is why the framers of

the Energy Policy Act required us to

promulgate regulations for state government fleets and for fuel providers.

As you know, those rules published

in March setting fleet requirements

are effective for model year 1997.

Look how far we've come in just

the past few years.

Ten years ago there were no directories for alternative fuel refueling

stations. Today, there are a thousandplus compressed natural gas refueling

stations alone that could be listed.

In 1992, there were NO formal

partnerships among the different 

levels of governments, fuel providers,

fleet agencies, and other interest

groups to promote alternative fuels 

in their community. Today, 48 U.S.

communities have joined our Clean

Cities Program already, and the list 

is growing. It is a program which

recognizes the vital importance of 

the private sector and the market and

which uses government as a consumer

and a catalyst rather than a regulator.

In addition to laying the groundwork for Clean Corridors across the

country, we will be creating export

opportunities for our domestic equipment manufactures by creating links

across borders and throughout the

Western Hemisphere to cities who

badly need the state-of-the-art technology that is produced right here in

the United States.

In 1992, there was no official program to train and certify mechanics

for alternative fuel vehicles. Today,

industry supports the Department's

training and certification efforts at

dozens of technical colleges across

the country . . . in collaboration with

EPA.
Our research partnerships are

producing the next generation of

advanced natural gas vehicles that

have a range of 300 miles per tank

and are ultra low on emissions.

Sometimes I think we lose

track of the simple logic needed to

stay on track. In closing, let’s just

remind ourselves of the basic

questions we need to repeat over

and over:

Do we need to reduce our

dependency on foreign oil? Yes

Do we need to protect our air

quality and health? Yes

Is there a single magic bullet

out there that will meet all these

challenges? No

Do we need to invest prudently

in a balanced clean energy strategy

that addresses both supply and

demand? Absolutely yes

When we align our actions

with those basic premises we will

have an American that's not only

better off, but an America that is

BETTER. Thank you.
Volume 5, Number 3

René Texeira, Editor

Jim Miller, 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/TP-425-22156

January 1997

Printed with a renewable-source ink on paper

containing at least 50% wastepaper, including

20% postconsumer waste

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.