Cleantech Market Intelligence
Wrightspeed Targets E-Truck Market
The medium and heavy duty truck industry has tried for years to join the rush to powertrain hybridization and electrification with very little success. The incremental cost has been difficult to justify for all but specific niche uses. New market entrant Wrightspeed recognizes this situation, and it is targeting its new integrated powertrain at a specific type of fleet that uses medium duty trucks with high annual mileage (30,000-plus miles) and a drive cycle that includes a lot of stopping and starting. The system is also suitable for heavy duty refuse trucks. The design is essentially a plug-in all-electric drive with a range-extending engine to recharge the battery pack.
Founder Ian Wright, a member of Elon Musk’s original team that established Tesla Motors, has focused on developing a system that addresses a well-defined niche in the truck market. Wrightspeed uses lithium ion (Li-ion) battery cells from A123 Systems to build a battery pack and installs its own thermal management system and charge management software. Electric motors are built by a supplier to proprietary design specifications, and the control software is also developed in-house. The system uses onboard individual wheel motors, and the software to control them is written by the company’s engineers. Wright believes that it is important for a powertrain supplier to develop the complete system, not just improve individual components.
The most dramatically different component is the choice of engine to provide charge to the battery pack. Wrightspeed has gone with a microturbine from Capstone Turbine Corp. This engine weighs approximately 220 lbs, about one-tenth of the mass of a typical diesel engine that can deliver similar power. And because it runs at very high speed, the generator attached is only about the size of a 1-liter bottle. The turbine can run on almost any liquid or gaseous fuel, and because of its burn efficiency, it does not need any exhaust after-treatment to remove toxic waste products.
Wrightspeed’s plan is to first address the replacement powertrain market for high-mileage medium duty trucks in large fleets, rather than aim at Tier One status with truck manufacturers. Wright believes that, once fleet managers have had experience with the unique features of his system, his company will be able to move up. Although it’s more expensive than a conventional diesel engine and transmission, the complete Wrightspeed solution of battery pack, electric motors, power electronics, and range-extending engine weighs about the same. The company reports substantial fuel savings from a combination of high-power regenerative braking and only running the engine in its most efficient mode. Average fuel economy figures are estimated by Wrightspeed to go from 8 mpg to 10 mpg with a conventional powertrain, to 25 mpg to 30 mpg with its replacement system. The powerful regenerative brakes also save significant maintenance costs for fleets, a major factor in the refuse truck market.
To date, Wrightspeed has reported orders for some test systems to be installed in garbage trucks, and FedEx ordered four units in February 2014, followed by an additional order for 25 more in July. Deliveries are scheduled for the first quarter of 2015, and this new approach to hybrid trucks will be interesting to watch.