FUEL DUEL: NATURAL GAS vs DIESEL

California is often a bellwether for the rest of us (Californians led on anti-smoking laws and automotive pollution-control devices, to cite two examples). That’s why it’s in the interest of anyone who operates in the city — whether you’re talking dumptrucks, refuse operations, construction or delivery vehicles — to pay close attention to what’s going on out there in Arnold Schwarzenegerland.

If nothing else, you might find out that it’s time to consider the switch to alternative-fuel hybrid engines. Some left-coast fleets have been through the hybrid maze already and you can learn from their efforts.

Transport Canada and Environment Canada, the two agencies that regulate engine emissions in this country, walk in virtual lockstep with their American counterpart, the U.S. Environmental Protection Agency. But the EPA has 900-pound gorillas of its own to deal with. One is the South Coast Air Quality Management District (AQMD). The AQMD monitors pollution for Orange County and major portions of Los Angeles, San Bernardino, and Riverside counties, where smog and politics are equally thick.

In 2000 and 2001, the AQMD adopted so-called “clean fleet” rules, including seven measures requiring operators of some heavy-duty vehicles to buy “clean-fueled” models when they replace or add units to their fleets of 15 or more vehicles.

Almost 6,000 alt-fueled trucks were added to the region’s fleets from 2002 to early 2004. Most of these are fueled by liquefied (LNG) or compressed natural gas (CNG).

The urgency has eased off, a bit. Last year, the U.S. Supreme Court ruled that the AQMD is not a state agency and has no authority to regulate privately held truck companies. So private California truckers are off the hook — for now.

But still, the time has come for fleet managers to decide whether alternative fuel vehicles are worth it. Jeff Campbell is director, product marketing for Cummins Westport. The company sells engines specially designed for alternative fuels manufactured by Cummins. “In order to succeed, natural-gas fueled engines have to stand on their own, without big incentives or laws that require them,” says Campbell.

“What we are seeing is that in instances where there is heavy fuel use — we’re talking refuse and transit markets — there will be an economic parity argument in 2007 and an economic advantage argument in 2010. And we include the cost of fueling infrastructure in that.”

Natural gas engines are well beyond the demonstration phase, though the early stages did teach manufacturers a few important lessons.

“We had some real early adopters who, frankly, had a hard time with their natural gas engines,” Campbell says. “The Toronto Transit Authority — a huge fleet and an ideal candidate for these engines — jumped in early but were using first-generation, mechanically controlled engines and had trouble. The word got out that the engines were unreliable.

“All our engines now are full-authority electronic. There’s a huge improvement in performance, reliability, and operating cost.”

However, the cost to convert is high. Waste Management Inc. operates the largest fleet of natural-gas-powered waste trucks in North America — more than 415 LNG and CNG vehicles. To ramp up the use of 125 LNG vehicles in San Diego, the company spent between $30,000 and $50,000 per vehicle. The big-ticket items are the company’s on-site fueling stations and dedicated maintenance bays: Waste Management spent between $600,000 and $900,000 US each, adding tanks, pumps, ventilation systems, piping, dispensers, and control systems.

The fueling infrastructure — the lack thereof — is a huge issue. There are currently few CNG or LNG fueling stations, and most are in urban areas in the western United States, although there are a handful in Canada as well. In many cases, the truck fleet supplies its own, meaning that natural gas is practical only for local operations.

However, the environmental benefits can’t be ignored, especially when running a “green” fleet is seen as good business. Paul Gagnon, director of fleet operations for Waste Management, says each engine produces 50 percent less NOx, 80 percent less particulate matter, and 11 percent less greenhouse gases. Furthermore, the California landfills where his trucks operate are capable of producing 800,000 gallons of LNG a day using methane captured at the site. That’s sufficient to fuel 15,000 vehicles.

Ironically, the emission-reduction strategies of diesel engine manufacturers represent both an opportunity and a threat to natural gas power. While the new engines will be running cleaner, the price of clean diesel will go up.

Between 2007 and 2010, the EPA is requiring particulate matter emissions levels to fall to 0.01 grams per brake horsepower hour (g/bhp-hr); NOx to drop to 0.2 g/bhp-hr; and non-methane hydrocarbon (NMHC) levels to not exceed 0.14 g/bhp-hr. Reaching these targets will require changes to diesel fuel: starting in June 2006, the sulphur content will drop from 350 parts per million (ppm) to 15 ppm. As a result, diesel engines will burn exceptionally clean, at levels that match natural gas.

However, truck makers estimate the new diesel engines will cost at least $10,000 more than they do today, with a loss of fuel economy. That’s going to hurt, because reducing the sulphur content is expected to add anywhere from 5 to 25 cents per gallon to the price of diesel.

Campbell and others in the business believe the rising acquisition and operating costs of diesel engines combined with improved performance and availability of natural gas power will generate interest that is genuinely market-driven.

“In North America, we’re going to get to a point where we have to recognize that these engines can compete with straight diesels in high-fuel-use service,” Campbell says. “In order to get cleaner, diesels will get more expensive. We’re already there on emissions, and our costs are going to come down.”

For some specialized fleets, down the road it may be incentive enough to switch.

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