The Whisper: Durable, Quiet City Bus Uses 25-40% Less Energy

APELDOORN, Netherlands, September 29 --

- Temporarily operating in the 2005 Apeldoorn bus schedule

The durable Appledoorn city bus called "The Whisper" will be able to achieve fuel savings of up to 25-40% after optimization. The current prototype uses 7.4 percent less fuel. This data was released Tuesday morning, September 28, during a meeting of the Whisper project partners: VDL Berkhof, Connexxion, the City of Apeldoorn, and e-Traction. After the test period, the Whisper prototype will be presented. It was developed over the past 18 months at a cost of EUR 800,000.

A second bus was available for test rides. Just like "The Whisper", this bus is driven by wheel hub motors.

Further Reduction of Energy Consumption

During the coming months, the Whisper will be modified in order to achieve a fuel consumption 25-40 percent lower than conventional buses. Some of the modifications will be smaller wheels and smaller, more efficient motors. This will reduce the vehicle's weight by 3,300 lbs. In addition, the bus will be equipped with tires with a lower rolling resistance. These measures, among others, as well as improved batteries will reduce energy consumption. After the optimization is completed, according to TNO, energy savings are expected to reach up to 40 percent, based on models and technical improvements. The improved Whisper bus will be spending several months next year in Apeldoorn's scheduled service. In addition, the first test series will be developed over the coming period, in preparation of serial production.

The Technology Behind the Bus

The Whisper bus is equipped with a revolutionary new drive system utilizing wheel hub motors. The batteries will be recharged overnight via the AC power system. During the day, they will be replenished by a combination of a diesel generator and recovery of braking energy.

This design does not only offer considerable advantages in comparison with conventional buses, but also concerning initiatives to improve environmental protection in public transportation. In addition to being more energy efficient and cleaner, The Whisper also is much quieter. Another advantage: the drive design can be adapted to existing buses.