Electric tractors star at Astra plant

General Motors has saved energy, improved productivity and optimised line side delivery operations at its Astra plant in Ellesmere Port since switching to electric tow tractors powered by Hawker batteries from EnerSys.

The new tractors, which replaced gaspowered units, also reduced vehicle movements in production and storage areas.

"We can use the new tractors right through the shift to deliver parts to the production line without any disruption to the operations," says Richie Mellor, senior engineer at the Worldwide Facilities Group, GMM Ellesmere Port Plant. "EnerSys and the tractor manufacturer have supplied us with a complete package that met our specification, delivered operational benefits and a number of savings." The company opted for a combination of 25 Linde P602 tow tractors and Hawker batteries with Hawker LifeSpeed high speed chargers. Trucks can be top-up charged for short periods during scheduled work breaks to maintain enough power to operate right through the shift. This is supplemented by overnight charging at the weekend, when the factory is shut down, to ensure the batteries are full for the start of the next week's shift.

The tractors do not need to go outside, so they are not exposed to rain and dirt.

One of the few disadvantages in switching from gas to electric power was the new wiring needed to supply the chargers. There was a cost involved but the site estimates it is saving around 50% on fuel which will offset the investment well within the projected lifetime of the tractors and batteries.