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Natural gas is the only proven alternative fuel

that can power heavy-duty vehicles weighing

more than 13 tons. The clear energy choice.

heavyalternative

We believe in natural gas. We believe it’s the fuel for the 21st century. For power generation. For vehicle fuel. As a domestic energy solution. Most important – to lower emissions. We figure that’s something worth talking about. We are Encana.

Learn more about natural gas and Encana at www.encana.com

75-95%

99%

70-90%

20-30%

89%

90%

Carbon monoxide

Sulfur dioxide

Nitrogen oxide

Particulate matter

Volatile organic compounds

Carbon dioxide

Emissions Reductions for Natural Gas Vehicles Compared to Diesel Trucks7

Field Tests of Natural Gas Vehicle Emissions8

CNG mail delivery trucks LNG buses* LNG semi-trucks LNG refuse trucks

LNG dual-fuel refuse trucks

fleet United Parcel Service (UPS)

Dallas Area Rapid Transit (DART) Raleys Waste Management

(WM)City of Los Angeles Bureau of Sanitation

number of alternative fuel vehicles 7 15 8 6** 10

number of diesel vehicles 3 5 3 2 3

drive cycle city suburban heavy-vehicle route

central business district five-mile route WM refuse

truck cycleair quality management

district refuse truck cycle

particulate matter (PM) reduction 95% NSS*** 96% 86% NSS***

nitrogen oxides (NOX) reduction 49% 17% 80% 32% 23%

non-methane hydrocarbons

(NMHC) reduction4% 96% 59% less than diesel

THC64% less than diesel

THC NSS***

carbon monoxide (CO) reduction 75% 95% -263% -80% NSS***

* DieselbusesinDARTstudyusedoxidationcatalysts.

** WM’sNOxtestsomittedthreetrucksduetomalfunctioningturbochargers;aproblemthatskewedresultsandhasbeensincefixed.

*** NSS:NotstatisticallysignificantbecauseemissionsweretoolowforthetestingequipmentfortheLNGbusesorbothLNGanddiesel(duetotheuseofcatalyzedparticulatefilters)refusetrucks.Emissiongiveninpercentagereducedfromdieselemissions,basedongramsemittedpermiledriven.Negativereductionvaluesindicateanincreaseinpollutants.

emissionsNatural gas can replace diesel fuel in heavy-duty vehicles (HDVs). Due to the variety of HDVs and drive cycles that natural gas can be used for, emissions benefits must be assessed for multiple working fleets. The U.S. National Renewable Energy Laboratory (NREL) and the University of West Virginia studied numerous fleets as part of the Alternative Fuel Truck Evaluation Project. The following table lists the natural gas vehicle emissions reductions as a percentage below the emissions of comparable diesel vehicles.

These field tests show that particulate matter (PM) is greatly reduced by natural gas to undetectable levels in two tests and by at least 85 percent in the other three. NOx is reduced by 17 to 80 percent compared to diesel. The reduction of non-methane hydrocarbons (NMHCs) varies widely, but all tests show a reduction. Two of the tests compare NMHCs from natural gas to the total hydrocarbons (including methane) from diesel, and both show the NMHCs to be 60 percent lower. The CO reduction varies widely from a near 100 percent reduction to a 260 percent increase, but the reports do not offer insight into this wide variance.8

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Sources1 www.en.wikipedia.org/wiki/Flammability_limit2 www.cleanairpower.com/duel-technology.php3 www.cumminswestport.com/pdf/CWI-ISL_G_Brochure_MED.pdf4 www.westport-hd.com/specifications.php5 Encanacalculation6 www.lincolncomposites.com/products/tuffshell-cng-fuel-tanks/7 NGVAmerica,EnvironmentalProtectionAgency,DOE,ChesapeakeEnergy8 www.afdc.energy.gov/afdc/vehicles/emissions_natural_gas.html

heavy alternativefueling solutionsIn 2008 Canada had 348,000 heavy trucks in use. These heavy trucks consumed 3.9 billion U.S. gallons of diesel and emitted 40.1 Mt CO2e. With new truck sales of 27,000 trucks per year there is a good opportunity for operators to dramatically reduce operating costs and emissions.

engine providersIn North America, Cummins is currently the only engine manufacturer that can provide CNG/LNG engine solutions. PACCAR (Kenworth and Peterbilt), Daimler (Freightliner, Sterling and Western Star) and MACK offer these engines. Other manufacturers are developing technology.

ISL G Ratings (8.9L)3

The Cummins Westport ISL G engine model is spark-ignited and operates on CNG or LNG.

engine modeladvertised HP (KW) @ RPM

peak torque LB-FT (N·M) @ RPM

governed speed (RPM)

ISL G 320 320 (239) @ 2,000 1,000 (1,356) @ 1,300 2,200

ISL G 300 300 (224) @ 2,100 860 (1,166) @ 1,300 2,200

ISL G 280 280 (209) @ 2,000 900 (1,220) @ 1,300 2,200

ISL G 260 260 (194) @ 2,200 660 (895) @ 1,300 2,200

ISL G 250 250 (186) @ 2,200 730 (990) @ 1,300 2,200

GX Ratings (15L)4

The Westport HD GX engine model operates on LNG. A small amount of diesel (about five percent) is injected to ignite the natural gas/air mixture.

engine model advertised horsepower (hp) peak torque @ 1,200 RPM

GX 475 475 1,750 lb – ft

GX 450 450 1,650 lb – ft

GX 400 400 1,450 lb – ft

vehicle payoutThe following chart describes a vehicle payout scenario.5

Payout of Incremental Purchase Costs for LNG Fueled Heavy-Duty Trucks

definitionsFuelsCompressed Natural Gas (CNG) is composed of approximately 95 percent methane and is normally stored at 3,600 pounds per square inch (psi). 1,000 cubic feet of natural gas has the equivalent amount of energy of 7.77 U.S. gallons of diesel.

Liquefied Natural Gas (LNG) is natural gas cryogenically stored at less than -160 degrees Celsius (˚C) at near atmospheric pressure. At this low temperature, LNG occupies 1/600 of the volume compared to atmospheric conditions. One U.S. gallon of diesel has the equivalent amount of energy of 1.71 LNG gallons. Fuel Characteristics and Comparisons1

auto ignition temp (C)

auto ignition temp (F)

fuel flammability range (%)

gasoline 280 536 1.4 to 7.6

diesel 256 494 0.7 to 5

ethanol 365 689 3.3 to 19

propane 480 842 2.1 to 10.1

natural gas 580 1,076 5 to 15

Engine types Dual fuel engines operate on a mixture of two fuels. Fuel is either fumigated into the air intake stream or directly injected into the combustion chamber. The fuels are stored in different tanks. Since natural gas does not spontaneously ignite under compression, a small amount of diesel is injected to ignite the gas. At full power diesel is typically 10 percent of the total fuel. Normal operation is ~90 percent natural gas fuel substitution. Technology and hardware are supplied by a non-Original Equipment Manufacturer (OEM) third party.2

Bi-fuel engines are typically CNG and gasoline and used in light to medium-duty vehicles. Bi-fuel engines are designed to switch from one fuel to another.

Dedicated natural gas engines utilize natural gas from a gaseous state. The storage differs with CNG stored in a compressed state and LNG stored in a liquid state. LNG is warmed up to a gaseous state and then injected into the engine.

definitions

Fuel tanksLNG fuel tanks: since LNG is a cryogenic fluid, a double-walled vacuum-insulated tank is used. A greater volume of fuel can be stored in the liquid state compared to compressed gas. LNG will be the fuel of choice for driving long distances. LNG fuel tanks are typically mounted in the standard saddle position but other frame and cab locations can be used.

LNG tanks

CNG tank6

CNG fuel tanks: local and return to base vehicles may have enough range to use compressed natural gas. New technology type IV tanks are constructed with an aluminum and/or plastic liner wrapped in carbon fiber to offer a strong lightweight unit.

assume: 40 litres/100 km, NGV premium for heavy duty - $80,000, no government incentives

fuel cost differential: diesel – LNG ($/litre)

payo

ut (

year

s)

trucks travelling 100,000 km/year

trucks travelling 200,000 km/year

trucks travelling 400,000 km/year

This document is designed to be a primer and provide information that will aid the end user to make an informed alternate fuel solution heavy truck purchase.

Questions or comments? Contact us at natural.gas@encana.com