ARE HYBRID VEHICLES a viable option for the commercial truck market?
The Society of Automotive Engineers (SAE) asked that question recently in a live, interactive webcast, “Business and Technological Issues for Hybrid Commercial Vehicles.” In a poll of fleet managers, engineers, educators, analysts, and journalists, the answer was mixed. But most tellingly, over 50% thought hybrid vehicles would be a reality and be practical in a few years.
“I don't think there's any question that at this given time, they are viable,” says Dan Benjamin, senior analyst for ABI Research, which provides analytical coverage of manufacturers and service companies participating in the technology market revolution. “Going forward, there is cause for optimism.”
A number of companies already have integrated diesel-electric hybrids into their fleets.
FedEx Express, in conjunction with Environmental Defense and Eaton Corporation, introduced the FedEx OptiFleet E700 into its delivery fleet in 2004. The new vehicle is expected to decrease particulate emissions by 96%, reduce smog-causing emissions by 65%, and travel 57% farther on a gallon of fuel, reducing fuel costs by over a third.
FedEx Express and Environmental Defense began working together in 2000 to create a delivery truck that would dramatically decrease emissions and fuel use. Eaton Corp was selected from more than 20 manufacturers that expressed interest in creating a cleaner vehicle using a variety of technologies.
Since the beginning of the project, progress toward goals has been assessed against the 1999 FedEx Express W700 standard delivery vehicle, which represents the most common model in the FedEx Express fleet.
The service launch of the new vehicle began March 2004, following tests in Sacramento, California, to demonstrate the commercial viability of the lower-emission powertrain in heavy-duty vehicles. FedEx Express currently has 18 hybrid trucks in service in Sacramento, New York, Tampa, Florida, and Washington, DC. New trucks are expected to be placed in Texas.
FedEx plans to add up to 75 new hybrids to its fleet by the spring of 2006. FedEx has placed a 30,000-unit order and plans to convert its entire fleet of mid-sized trucks to diesel-electric hybrids over the next 10 years during the normal replacement cycle.
International's bucket trucks
In October, utility and state truck fleets working together in WestStart's Hybrid Truck Users Forum (HTUF) program selected Eaton and International Truck and Engine Corporation to build more than 20 advanced, pre-production hybrid-electric bucket trucks (4000 series) for national deployment and assessment.
A version of Eaton's permanent magnet electric motors has been mated by International to its own 7.6L diesel engines — which have 225 hp and 560 lb-ft of torque.
The trucks, which include silent boom operation and auxiliary power generation (up to 25 kW), promise to improve fuel economy by 40-60%, provide engine-off work site operation, reduce maintenance costs, and further cut emissions from this class of truck. Coupled to that, the trucks offer a “dual use” benefit that supports both commercial truck needs and emerging military needs for efficient drivelines.
“This project takes hybrid truck systems to the next level of commercialization,” says John Boesel, president and CEO of WestStart-CALSTART, which operates the Hybrid Truck Users Forum program in a partnership with the US Army's National Automotive Center (NAC). “These are not prototype trucks. They are the early production versions of what we expect will be commercially available trucks in the next two to four years.”
HTUF is a joint program between WestStart-CALSTART and the NAC to speed the commercialization of hybrid drivelines that could be used in both military and commercial vehicles. The HTUF program enjoys the participation of over 50 fleets representing roughly one million trucks. HTUF has worked with fleets and suppliers to identify the best, first-market segments for hybrid trucks and has organized fleet working groups around those applications. The best uses are generally for urban work trucks, especially those with heavy stop-and-go or urban driving, and also those with high engine idling times.
HTUF's Utility Working Group developed performance specifications for a hybrid bucket truck, including a 50% increase in fuel economy, reliability equal to today, the ability to perform repair work with the engine shut down, and the ability to generate electricity for emergency and other use. Twelve core fleets committed to purchase pre-production trucks that met these requirements. A nationwide request for proposals was sent to truck makers and suppliers, leading to a detailed selection process of the finalists that ended with the selection of the Eaton and International team.
“These initial findings support our vision of making diesel-electric hybrid trucks a viable option,” says George Survant, director of fleet services for Florida Power and Light Company and chair of the HTUF Utility Working Group. “The other benefits we expect, such as extended maintenance intervals and fewer brake changes, further illustrate the promise of this technology.
“These trucks make sense because the users themselves developed the requirements. We spent considerable time jointly assessing what kind of performance, fuel economy gains, and new capabilities will make a business case for our operations. If these trucks now prove out these capabilities and costs, our fleets are prepared to start buying them in the coming years as our replacement vehicle.”
In addition to Florida Power & Light Co, the main fleets committed to the deployment purchase are Alabama Power, American Electric Power, Baltimore Gas & Electric, Duke Energy, Entergy, Georgia Power, Hydro Quebec, Missouri Department of Transportation, Pacific Gas & Electric Co, Pepco, Southern California Edison, and TXU Electric Delivery.
Azure Dynamics Corp, which is involved in proprietary hybrid electric vehicle technology — focusing on urban commercial vehicles and military vehicles — has customers including Purolator, Charmer-Sunbelt, Canada Post, London Taxis International, US Postal Service, Renault Trucks UK, AM General, US DOD, and SEV Group.
Azure and Purolator signed a supply agreement for up to 2000 units over a five-year period, with an approximate value of Canadian $90 million.
“The technology and its reliability passed with flying colors, giving us the confidence to place this order and to plan an ongoing program of fleet replacement,” says senior vice president Ray Pederson.
Says Ricardo Espinosa, vice president of engineering for Azure Dynamics, “We've had extremely good feedback. This started four years ago, when we built the original series vehicles and immediately developed vehicles we've loaned to customers for periods of one to two weeks, vehicles we've had in China for six months being evaluated by government agencies. The positive feedback is shown by the commitment of Purolator.”
The Bronx Community Clean Vehicle program includes five hybrid shuttle buses with Azure components, a Workhorse chassis, and Thor/Champion body.
How does it work?
Eaton's hybrid-electric powertrain combines a diesel engine and electric motor to drive the vehicle. A computer determines the most efficient combination, depending on current operating conditions and driver demand.
A four-cylinder engine replaces the six-cylinder version currently used in the FedEx Express W700 delivery vehicle. The engine size is reduced because of the added power provided by the electric motor. A particulate trap has been added to the truck to further reduce emissions.
Batteries capture and store energy during the “regenerative braking” phase of the vehicle's operation, providing a source of stored electric power for the motor during future acceleration. Therefore, all electrical charging of the battery is provided by the hybrid electric powertrain, and no external electrical infrastructure, such as a power cord or electrical outlet, is needed.
The trucks are ideally suited for the frequent stop-and-go delivery pattern required in cities. When a driver hits the brakes on the hybrid, the batteries capture and store energy that is usually lost during deceleration. On acceleration, the batteries release the stored energy to produce a smooth acceleration that's quiet and fuel-efficient.
Eaton's hybrid electric powertrain has been placed in the standard white FedEx Express W700 delivery truck, which utilizes a Freightliner chassis and a Utilimaster body. The hybrid electric E700 has a Gross Vehicle Weight (GVW) of approximately 16,000 lb and a cargo capacity of approximately 670 cubic feet.
“The FedEx comments we're getting back are that there are regular driving characteristics,” Eaton senior chief engineer Jeffrey Carpenter says. “The drivers are getting into these vehicles and not seeing much of a difference — which we take as the ultimate compliment. If we can make this technology seamless to them, then we think we've accomplished our goal.”
Carpenter says the benefits of the Eaton system include: only one electric motor and inverter, which provides a lower cost and improved reliability; the motor is relatively low speed/high torque (44kW and 420 Nm); and “direct” architecture has reduced complexity, lower cost, and more reliability, an engine-only fallback operating mode, and AutoClutch and a layout that allows for a high degree of functionality.
The Charmer-Sunbelt project involves a Class 7 Kenworth TC300 that is equipped with a parallel hybrid electric system with automatic transmission and all components and ultra-capacitors packaged under the chassis.
A parallel hybrid has an electric motor and combustion engine, each of which powers the vehicle at different times, and sometimes simultaneously. Each powerplant may be smaller than the engine in a conventional vehicle, and generally is joined by either a planetary gearset or a group of clutches. This system is far less demanding with regard to the required size of the electrical reservoir, and accordingly, the cost and weight of the batteries.
(Contrast that with the series hybrid, which has an electric motor that is solely responsible for propelling the vehicle. The combustion engine is solely responsible for powering a generator to charge batteries. Mechanically, it's the simplest form of hybrid, requiring electric motor output roughly equal in function to the engine in a conventional vehicle, plus a similarly-sized combustion engine for power generation. Series hybrid is the primary architecture for the plug-in hybrid.)
Espinosa says the advantage of Azure hybrid electric vehicles include: fuel is used more efficiently; the smaller, lighter engine drives the generator to power the traction motor as well as charges the battery on the series vehicle; the engine is sized for highway performance and provides identical high-speed performance on a parallel vehicle; the energy-storage system powers an electric motor when in electric mode; the engine shuts down when not in use, idle, and while moving; they do not need to be plugged in; and they operate quietly.
He says the direct advantages of hybrid systems in general are: fuel consumption is reduced by 30-50%; environmental efficiency at low speeds; same cruising power as conventional vehicles; eliminate exhaust in warehouse when set to electric-vehicle mode; create healthier environment for workers; an overall cleaner fleet without infrastructure challenges; and reduced maintenance and therefore lower operating expenses.
For example, Eaton says that if 10,000 hybrid electric vehicles were on the road rather than current standard vehicles, substantial reductions in emissions and fuel use would occur annually:
Smog-causing emissions of nitrogen oxides would be reduced by 1700 tons annually — the equivalent of taking passenger cars off New York City roads for 25 days.
Carbon dioxide emissions would be reduced by 83,000 tons annually — the equivalent to planting two million trees.
Diesel fuel usage would be reduced by 7.2 million gallons, which requires one million barrels of crude oil to produce.
Benjamin says that market forces affecting hybrid deployment include the initial cost, fuel economy/operating cost savings, collateral benefits, and legislation.
- Initial cost.
“It's a major issue,” he says.
He says there is a $100,000 premium for the parallel hybrid drivetrain of 40' transit buses, $200,000 for series hybrids, and just under $20,000 for light- and medium-duty trucks (up to 19,000 GVW).
“The pricing will be interesting going forward. We think we're going to see hybrid drivetrains going for under a $20,000 premium simply because there are going to be vendors out there who are going to be able to leverage their consumer hybrid technology. That's something you might see on a light-duty pickup truck, but just enlarged a bit and reissue the design and some of the components for light- and medium-duty trucks. If those are going for under $5,000 in the consumer area, it should not be a stretch to get it to go under $20,000 in the commercial area.
The cost and viability for long-haul trucking and specialized vehicles remains unknown “just because long-haul trucking tends to feature more highway mileage and has weight and braking requirements. That won't necessarily be helped or hurt by hybrid vehicles, but could — just because of the size of the vehicles — really boost the initial price of the systems.”
- Fuel economy/operating cost savings.
Benjamin says Year 2002 generation series hybrid buses produced 22% higher fuel economy; Seattle parallel hybrid buses produced roughly 10% improvement; and Hino Class 4 parallel hybrid trucks 14-27%.
“We only wanted to show you publicly available figures. These are on the conservative side, and have been out there for a period of time. We've heard higher figures, but we wanted to make sure we didn't go with anything that anybody hasn't committed to publicly.”
At $2.50 a gallon, the break-even lifetime mileage is 1.2 million miles for a parallel hybrid bus, 1.1 million miles for a series hybrid bus, and 670,000 miles for a parallel hybrid Class 6. At $5.50 a gallon, it's 530,000 miles for a parallel hybrid bus, 480,000 for a series hybrid bus, and 310,000 for a parallel hybrid Class 6.
“This doesn't factor in interest rates or improvements to maintenance, which can be sizable, especially with some of the braking systems. It also doesn't necessarily take into account what type of refurbishment costs are going to be necessary with battery systems, and that can be an issue and is something that hasn't been fully established.
“At $5.50 a gallon, these lifetime mileages become far more palatable, especially that 310,000 miles for Class 6. If you can get it to the 20-30% level, you can definitely start looking at vehicles that are going to pay for themselves and reduce the total cost of ownership. At $5.50, it does start making sense to go with hybrid systems. Despite that fact, there has been less development and less interest in Europe than in North America. To us, that doesn't make a lot of sense.”
- Collateral benefits.
He says there are reduced maintenance costs, most notably in brake and engine wear.
Hybridized electrical architecture has secondary uses: refrigeration, waste disposal, construction vehicles, portable generators, and silent running for night-time operations.
“If these can be used to replace hydraulics, which are quite noisy, they can be used for night-time operation for garbage hauling and construction. It would create a market for vehicles that don't exist right now using these conventional methods.”
He also says hybrids can be a potential method for meeting new braking requirements.
“In the US and elsewhere in the world, there are some limited programs to help deduct certain portions of the initial hybrid vehicle expense. This is something that will bring the total cost down.”
Here are some questions that Benjamin, Carpenter, and Espinosa fielded from webcast listeners:
Q: Do you foresee urban delivery trucks moving to gasoline-electric hybrids v. diesel-electric?
Carpenter: “I think that's a function of the GVW of the vehicle and the customer's preference. There's a lot of preference in California for the gasoline engine. To me, it's a customer-application choice.”
Benjamin: “If you look at some of the diesel regulations for commercial vehicles in certain geographic regions where there's already a legislative effort — particularly in Japan — that might be more limiting to diesel vehicles. Gasoline becomes a much more viable alternative, even for commercial vehicles.”
Q: In view of break-even figures showing a half-million miles and the fact that the beneficiaries are not over-the-road vehicles where such mileage is common but delivery vehicles that generally have 25,000-30,000 miles per year of service, how can you see these as anything more than a niche market?
Benjamin: “The fuel economy numbers are very conservative. They're showing existing systems, rather than the systems that might be in place in a couple of years, where we'd be able to take advantage of the benefits of system design and refinement. That was only assuming a 12% improvement in fuel economy, and already some of the preliminary results are considerably higher. If you cut that number in half to 250,000 with the 30,000-per-year figure, you're already right around the break-even point. It just shows we're not there yet.”
Q: You're at a break-even point of 10 years, but fleet operators I've talked to are looking for two- to three-year payback on new investments.
Benjamin: “There are other issues there that would make hybrids beneficial, even with longer-term payback. With certain emissions regulations, hybrids can aid. With regard to potentially changing EPFs and selective catalytic reduction … those are all areas where hybrids can aid at a partial load point. I think that argument will only get more compelling.”