April 30, 2009 Volvo’s new hybrid bus is taking on passengers for the first time with field tests now underway in Gothenburg.

The Volvo 7700

Volvo uses a parallel hybrid technology which combines a smaller than normal diesel engine and an electric drive which can be used together or separately. When the bus stops to drop off passengers, the diesel engine automatically shuts off and doesn't restart until the vehicle has reached a speed of 15-20 km/h using electric power – all making for a much quieter bus stop.

Regenerative braking is also used in the system which Volvo says achieves fuel savings of up to 30%. Particulate discharge and nitrous oxides are reduced by 40-50% compared with a diesel only bus and carbon dioxide is reduced by up to 30%. The company also estimates that bus operators will recoup the extra cost of the vehicle within seven years.

The added bonus of a hybrid bus is that these savings are combined with the inherent benefits of public transport.

“We reduce energy consumption per passenger by 50-75%, compared with using an automobile,” says Edward Jobson, Environmental Director at Volvo Buses. “With such major environmental gains and such large savings in fuel costs, we are convinced that hybrid buses will become extremely attractive and a difficult-to-beat alternative for personal transportation within a few years.”

Volvo's has also designed its hybrid architecture to be common for buses, trucks and construction equipment with a view to producing larger volumes and lowering component costs.

Volume production scheduled for 2010

Göteborgs Spårvägar transit company is participating in the current field test and Volvo expects to start series production of hybrid buses at the beginning of 2010. Field tests will soon commence in London with the first of six hybrid double-decker buses.

David Greig