Buses account for a significant amount of air pollution and have always been known as notorious fuel users,  but all of that could change if a company called UQM Technologies Inc. gets the chance the install their Power Phase electric propulsion system into buses of the future.

UQM Technologies is a developer of alternative energy technologies.  They specialize in power dense, high output electric motors, generators, and electronic controllers for several fields including automotive and industrial uses.

Recently, UQM installed a PowerPhase system in a 35 foot Proterra FCBE Transit Bus.  The bus is capable of carrying 72 passengers and has a fully loaded weight of 36,680 pounds.  With the help of the UQM system, the bus was able to obtain up to 29.23 miles per gallon throughout the course of a typical commuter bus stop schedule.  The bus also achieved 21.35 mpg in a congested urban setting, and 17.55 in a suburban setting.  Electric vehicles use a converted fuel usage number that takes into account the fuel used to provide the electricity needed for charging it.

The PowerPhase system produces peak torque of 650 N-m and 201 horsepower from a 150kW motor.  Moving a big bus is all about torque and the UQM system provides plenty.  The entire system can be charged to capacity in only 10 minutes through a newly designed fast charge system called the TerraVolt Energy Storage System.

The fuel mileage numbers are indeed impressive.  Recent tests between the UQM bus and a traditional lightweight transit bus reveal that the UQM system shows improvement over diesel versions of more than 400%.  This allows the bus to travel further along routes while using less fuel and creating less pollutants.

The UQM system looks promising, but suffers from one fault that all hybrids do.  If you turn the air conditioning or heater on in the bus, fuel mileage drops by about 30%.  A small problem, but UQM is working on a solution.  Even with the heater on full blast, it will still provide a 370% advantage over its diesel counterpart.

Source:  UQM Technologies Incorporated