Battery-electric motorcoaches are expected to deliver significantly lower lifetime costs than comparable diesel-powered vehicles, but the first buses may be on the road before the numbers are calculated.
“We are looking right now at how to take the reduction in operating costs and compare that to the acquisition and infrastructure costs,” said Thom Peebles, vice president of marketing at ABC Companies, the North American distributor for Van Hool. “When we go into testing models in the real world we will be able to determine real costs, lifecycles, emission reductions and what it will cost to put charging infrastructure in place.”
Purchase costs could be higher due to the prices for battery packs, but there could be offsets for the reduced complexity of electric components. It also is assumed that operating costs for battery motorcoaches will be lower due to expected savings in maintenance and energy. Manufacturers say there will be several new expenses but then savings that offset those.
“There are a number of factors that are going to drive the operating cost equation, which include vehicle maintenance then your economy and fuel equivalent,” said J.P. Pelletier, vice president of engineering for Motor Coach Industries in Winnipeg.
“We know maintenance is going down because there are fewer moving components. Some of the components, like the drive motor, have been around for a while and are proven,” he said. “Then your costs will depend on what your local cost is for diesel versus electricity and whether you’re paying a premium for electricity based on your recharging practices.”
Much of the current standard maintenance, things like oil changes, will go away, notes Peebles. Energy costs will differ dramatically, depending on whether charging is done during peak or off-peak times. But he said: “In looking at electricity and diesel, we know that in most cases electricity is going to win.”
Simplicity of electric vehicles continues through the gearbox. Current Proterra buses transmit torque through a “two-speed auto-shift EV gearbox” while some electric motorcoaches, thanks to the wide operating range of electric motors, dispense with transmissions. BYD buses carry “dual in-wheel traction motors” and the MCI J4500e will utilize a “4.7 gear ratio direct drive” to the wheels.
Batteries will account for a big chunk of the invoice price for a new electric motorcoach, but those costs are still uncertain, Peebles said, since battery capacity keeps increasing dramatically and battery costs are declining at the same time.
Ongoing testing will allow engineers to determine how much initial battery capacity is needed to maintain an acceptable operating range after years of anticipated battery fade, said Brent
Maitland, vice president of marketing and product planning at MCI.
“We have to plan for vehicles to go the required distance over a long period of time, whether that is seven, 10 or 12 years. People are not going to cut us any slack if the electric coach only goes three-quarters of the distance we promised.”
Also developing are projections for battery replacement costs.
“You are going to see the batteries, over time, fade in terms of how much power they can provide,” Pelletier said. “We are continuing to learn what that fade will be. The vehicle and system has been designed to replace modules within the battery packs so you don’t have to do a full coach battery replacement at one time.”
A market for used batteries may offset replacement costs, Pelletier said. “There is an industry being created for recycled batteries.”
Batteries that no longer provide adequate capacity for road travel might remain useful for stationary storage, such as holding off-peak electricity for industrial operations or motorcoach recharging during the more expensive peak daytime hours.
MCI is testing a prototype of its first battery-electric motorcoach, the J4500e, and plans to apply the technology to its D45 CRTe LE commuter coach. ABC Companies is partnering with the Proterra battery technology company on a prototype CX45E that is being constructed by Van Hool in Belgium and is expected to be delivered by the end of the year.