Giving the Earth a Brake
Hybrids are not just for tree-huggers anymore, as heavy-duty rigs using regenerative braking technology are hitting the marketplace.
by James Menzies
As recently as a few years ago, the idea of applying hybridelectric technology to heavy-duty trucks was preposterous. After all, how many logs can you haul when you need a 53-foot trailer full of batteries? But recent advances in hybrid technology have broadened the marketplace for the environmentally friendly alternative. And now, truck manufacturers are eyeing the heavy-duty market.
Hybrid-electric power trains use regenerative braking, allowing the vehicle to recapture energy normally lost while braking, and store it in ultracapacitors. That energy can then be used to help power the vehicle when required, or to run auxiliary devices such as loaders.
There are several benefits to the technology. For starters, fuel consumption can be reduced by up to 35% in stop-and-go applications. However, it's more likely to be in the range of 4-7% in heavy-duty vocations. Hybrids also reduce brake wear, and allow operators to spec' a smaller diesel engine because the electric motor generates up to 160 hp. Also, the electric motor delivers full torque as soon as the throttle is applied which improves performance and efficiency.
Technology Available
Volvo and Mack were the first truck OEMs to expand their hybrid technology to the heavy-duty market. In a joint announcement earlier this year, the companies rolled out their I-SAM (Integrated Starter Alternator Motor) technology for heavy-duty trucks. The system consists of: a traditional diesel engine; an automated mechanical transmission; an electric motor; a power/electronics box; an energy storage box; and a power train control unit.
At the recent Mid-America Trucking Show - the trucking industry's largest trade show and a showcase for new technology - Peterbilt also announced plans to begin building a heavy-duty hybrid version of its Model 386. It will be rolled out to the market in 2010.
"Peterbilt's hybrid initiatives include development of both medium- and heavy-duty vehicle platforms and for both on-highway and vocational applications," said Bill Jackson, general manager of Peterbilt and vice-president of PACCAR. "We will introduce hybrid vehicle solutions to serve a broad range of business requirements, helping customers reduce operating expenses and fostering greater environmental stewardship."
Of particular interest to the logging industry, hybrid-electric systems can generate auxiliary power, in some cases eliminating the need for a power takeoff (PTO).
"Operating a forestry truck equipped with a loader would make it possible to recover braking energy when the vehicle travels on forestry roads," FERIC pointed out in a recent version of its energy efficiency newsletter. "The vehicle would use this energy during non-working time (loading and unloading, waiting, idling, powering of other auxiliary systems and devices), and during times when power needs are lower (travelling unloaded, on-highway, etc.)"
Component manufacturers Eaton and ArvinMeritor have also thrown their hat into the ring, introducing their own hybrid-electric systems. Eaton's will be available by 2010 and ArvinMeritor is currently working with Wal-Mart to develop a hybrid-electric system based on a standard Cummins diesel engine.
The ROI Case
There is clearly potential for hybrid technology in the logging industry. However, there's one problem - the cost. The systems are cost-prohibitive, so even if double-digit fuel savings are achieved (which they probably wouldn't be on routes consisting predominantly of highway miles), the vehicles would not likely deliver a return on investment for contractors.
"We can't sell a lot of these right off the shelf," admits Paul Vikner, president and CEO of Mack Trucks. Until hybrid-electric vehicles are produced in higher volumes, the cost of building them won't decrease. And there's the rub - until the up-front cost decreases, these trucks are not likely to be purchased in any significant volumes.
Mack and Volvo officials would like to see government incentives provided for forward-thinking fleets that don't mind spending a little extra on their trucks. They'd also be acting as guinea pigs, as this technology is still largely unproven in heavy-duty applications.
Vikner said financial incentives would "jump start" the use of heavy-duty hybrids. He also said that fears about reliability and operating costs would be alleviated once they are more widely used in real-world applications.
Yet there is little reason for optimism on the government subsidy front, here or in the US. While incentives are now available for customers who purchase hybrid passenger vehicles, there are no such perks for heavy-duty commercial customers. Until that changes, it appears hybrid-electric vehicles are destined to remain a mainstay in only the municipal and local medium-duty delivery markets.
The Log Haul is a regular column on log hauling issues and technology. James Menzies is executive editor of CanadaÕs leading trucking magazines, Truck News and Trucks West. He writes this column exclusively for CFI Magazine. He can be reached at jmenzies@trucknews.com.
