Hybrid buses to drive green trends

Siemens Vietnam and the country’s leading bus-maker Vinamotor last week signed a cooperative deal to apply Siemens ELFA hybrid drive technology for urban buses in Vietnam, with a  prototype  to be built this year.

Siemens will supply all necessary ELFA components and provide technical support, while Vinamotor will prepare the platform and manufacture the remaining parts. With the technology, city buses can reduce fuel consumption by up to 50 per cent and significantly save operating costs.

“Siemens’ state-of-the-art and environment friendly technology will help improve the quality of our buses thus enabling our customers to have a wider selection of a suitable vehicle, and help us implement efficiently directions from the government and the Ministry of Transport on development of manufacturing buses which are safe, environmental friendly, energy saving and cleaner-fuel-driven,” said Vinamotor chairman Do Nga Viet.  

Siemens Vietnam president Erdal Elverand said: “We understand very well the challenges facing big cities in Vietnam, particularly in transport systems. Siemens has an extensive portfolio of technologies for major urban centres and is committed to providing our best support to improve the current situation and our partnership with Vinamotor in this hybrid bus project is a strong evidence of our commitment.”

Le Manh Hung, deputy minister of Transport, said the government had approved the public passenger transportation strategy till 2020, which underlined the use of environmental-friendly buses and their increased public use.  

ELFA is a diesel-electric hybrid concept which combines mobile power supply modules such as diesel generator sets and high performance energy storage devices. These allow the energy which is released during braking to be stored.

In conventional city buses, braking energy is converted into heat and lost. With the ELFA hybrid technology, braking energy is converted into electrical energy by the regenerative operation of the traction motor and is fed into an energy storage device – in high-performance capacitors or batteries.

The stored energy is reused during starting and acceleration. Depending on the storage capacity of the system, the bus can also be driven purely electrically  emission-free. As such, operating companies can benefit from significant fuel cost savings of up to 50 per cent and reduce environmental impacts through lower exhaust emissions.