Proterra Catalyst electric bus sets records at Altoona in efficiency, gradeability, weight and acceleration
Proterra has completed the structural testing program at the Altoona Bus Research and Testing Center with its new Catalyst battery-electric bus (earlier post), in the process setting records for efficiency, gradeability, weight and acceleration. The full public Altoona report is available here.
While conventional diesel buses average 3.86 mpg (60.9 l/100 km), the Proterra Catalyst achieved the best overall average fuel consumption rating yet for a 40' transit bus at 22.16 MPGe (equivalent to 10.7 l/100 km) (1.70 kWh/mile). Nearly six times more efficient than a diesel or CNG bus, the Catalyst is also ~15% more energy efficient per mile than its closest competitor’s electric bus on the same test (BYD, which averaged 1.988 kWh/mile), which translates to a lower lifetime energy consumption of 15%. Proterra’s new 40' bus is more energy efficient per mile than most light-duty trucks and SUVs on the road today.
|Partial summary of energy economy results from Altoona report. Click to enlarge.|
In addition to energy efficiency, the Proterra Catalyst broke records in gradeability, weight, and acceleration.
Gradeability has been a historic obstacle for electric buses, which until now, weighed more and had less power, making steep inclines difficult if not impossible to climb. The Catalyst conquered a 15.5% grade, unprecedented in this test by an electric bus, making it an option to serve metropolitan areas with challenging topography in West Coast cities, including San Francisco and Seattle.
Made of carbon fiber and advanced composite materials, Proterra’s unibody design is a prime driver for its high performance with regard to weight and durability. With a curb weight of 27,370 lbs (12,415 kg), the Proterra Catalyst is not only lighter than any other electric bus, leading to greater efficiency, but is also more durable than buses made of aluminum or steel and less prone to corrosion. The transit industry has traditionally struggled with vehicle weight, especially for new technologies like hybrid, CNG and EV. By designing the vehicle from the ground-up, using the most advanced technology and materials, Proterra has eliminated the vehicle weight concern for EV.
The Proterra 40' Catalyst also achieved 0-20 mph acceleration in 6.7 seconds. Rapid acceleration is particularly critical for keeping routes running on time, allowing bus operators to move in and out of traffic with greater ease.
The Proterra Catalyst drivetrain features a 220 kW peak permanent magnet drive motor delivering 678 N·m (500 lb-ft) of torque, coupled to the Proterra 2-speed auto-shift EV transmission. The bus is powered either by an advanced Lithium Titanate fast-charge energy storage pack or an NMC extended range energy storage system.
To break not one, but four records at Altoona is a major milestone not just for us, but for the industry as a whole and is a testament to how far electric bus technology has come. In an industry hungry for innovation, to receive these kinds of results from rigorous testing organizations such as Altoona helps to assure transit managers and civic leaders that electric buses can outperform fossil fuel vehicles and are a durable and reliable investment.—Ryan Popple, CEO of Proterra