According to Andy Douglas, Kenworth’s national sales manager for specialty markets, the third annual update on Kenworth’s natural gas (NG) progress has customers approaching the topic more proactively. Attitudes are changing from “let’s talk about it” to “let’s do it.”
Early trials are turning into orders as the whole NG experience goes from a “science project” to a solid business model, he said.
To underscore the point, a small trucking press group was invited to spend some informal time with
Douglas and drive a selection of Kenworth trucks that had been assembled for the NG demo.
The KW Lineup
The Kenworth NG lineup covers the available market with engines from Cummins Westport and from Westport. This may seem confusing, but in simple terms, there is a 9-liter ISL-G and the just-available 11.9-liter ISX 12G, both of which are joint venture Cummins and Vancouver, Canada-based Westport products. These are spark-ignition NG engines. Then there is the15-liter GX, which is pure Westport and features a diesel-pilot injection, with secondary injection of NG to develop the power stroke. It is, however, based on the Cummins ISX 15.
These three engines are available in Kenworth T440, T470, T660, T800, T800 SH (short-hood) and W900 Sloped-Hood models (See chart above). As yet, none of the New
Generation 680/880 models are included in the NG lineup.
Of these, the ISL-G and the ISX 12G can be liquified or compressed natural gas fueled (LNG or CNG). The GX 15-liter is only available fueled by LNG.
The demo trucks lined up at the event included T440, T800 and T800 SH. As a further complexity, different fueling systems were featured, with long-term LNG partner Trilogy supplying some and relative newcomer Agility also represented. Trilogy offered a back-of-cab CNG “cabinet” for the T800 SH.
Douglas said this underscores the gaining legitimacy of NG as a viable fuel. Also, more competition means more innovation. This should mean the price of gas storage on the truck—to date one of the major obstacles to its widespread adoption—will start to come down. It’s a self-fulfilling process, Douglas added: as prices fall and demand picks up, increased volume will see prices falling yet more.
Getting on the gas
The Westport 15-liter has been around for several years and we have driven that in various situations, including a drive of 100 mi. or so pulling a loaded trailer in Washington. There, the conclusion was that the 15-liter is easily able to hold its own against a diesel and at significant savings in fuel cost, once the issues of infrastructure are resolved.
But the engine that had our focus—and very much that of alternate fuel customers—is the newly-arrived 12-liter Cummins Westport. That, said Douglas, has everyone’s attention as the current 350 and upcoming 400 have the muscle to replace a broad swath of engines in regional, line-haul and vocations where the already available 9-liter is pushed to deliver.
The 9-liter is more than adequate for P&D applications, as very successful demonstrations—and orders—at Coca-Cola and an Indianapolis bottling fleet Monarch Beverage attest. Coca-Cola has placed multi-truck orders for 9-liter gas distribution trucks, while Monarch has said it is the company’s intention to run a fleet with 85% of the trucks NG-powered.
The whole NG scene got a boost with a recent announcement by UPS that its 800 tractor orders for the package fleet in 2014 would include no diesel-fueled units. Some will be CNG and some LNG, said UPS COO David Abney at the recent ACT Expo in Washington, D.C., but all will be NG. Kenworth is to get a major share of that, and certainly a good number of those units will be powered by the ISX 12G.
So our decision was to zero in on the 9-liter and the new 12, driving first a T440 P&D tractor-trailer around an urban course that included Highway 159 through the middle of Chillicothe. This was followed by a stint with a T800SH with the ISX 12G. Both of these were CNG fueled, the first with tanks by Agility, the second with the back-of-cab Trilogy setup. As a bonus, there was a roll-back chassis, unloaded, with the 12G that proved to be such a rocket ship that it was returned after only a couple of convincing miles.
The 9-liter ISL-G is adequate for the P&D role, but it undoubtedly has to work for a living. It is a bit noisy—
despite the low-noise combustion of NG—as it has to turn a lot more RPMs to get the job done. Where we are used to keeping diesels in the low teens, the ISL needs to rev out to 2,200 RPMs on a regular basis to keep up with traffic. The progress is aided by the well-matched Allison transmission that is a part of the ISL-G package, but when the fan kicks in as well, it’s all a little raucous.
The 12G is entirely different. It drives more like a diesel in that low speed torque is on the generous side of adequate. The demo truck had a nine-speed Eaton manual, so the usual 1,500 RPM shift points were used and the truck made good progress, picking up the next gear well and getting on down the road. But it took some driving. The response to the throttle is very different from a diesel’s. There appears to be some surge, so that gearshifts are not quite as intuitive—nor as smooth, let it be said—as driving a well-mannered diesel. The biggest difficulty was accelerating away, which required very little throttle or time in gear. The hardest shift was in the four-five and five-six, where considerable care has to be taken to back the throttle to zero before making the shift to get even a semblance of a smooth change.
The other rather disconcerting thing was the peculiar noise that accompanies deceleration of the engine.
Cummins calls it a “bark,” and it is caused by the sudden release of boost pressure with the closing of the throttle. It’s very odd and like nothing as pleasing as the waste-gate pressure release on a Golf GTI or a Subaru WRX, for instance. However, it did not impede the progress of the vehicle around the busy route of the demonstration.
At the end of the day, it was a convincing demonstration that NG in the shape of these three Cummins engines is a viable proposition, providing other factors are accounted for, most notably infrastructure concerns and the type of operation the truck is going to see. Still, there is that feeling that the technology is evolving. As it should. Just think about it: the diesel has been in trucks since 1931 when Clessie Cummins put his engine in an Indiana truck and drove it coast-to-coast. That’s 80+ years of development. NG heavy-duty engines have come a long way in a far shorter time and they will undoubtedly see a lot more development as we go forward.
But again, referring to Andy Douglas’ opening comment, it’s no longer a science project. These trucks are relevant now, here to stay and with the fast-paced development of infrastructure and on-board fueling, they become more and more viable every day.