Volvo has been picked by the Swedish Energy Agency to apply hybrid powertrain technology to heavy vehicles. The vehicles: two garbage trucks in the cities of Gothenburg and Stockholm. The goal: to use 30 percent less fuel, give or take. The haul: SEK 9.8 million ($1.4 million) to Volvo.
The trucks should be hauling trash by early 2008, and will be tested and evaluated over three years — as will a new Volvo safety system designed for city traffic. The parallel hybrid system Volvo will use is a variation on the I-SAM (Integrated Starter, Alternator, Motor) system used in the USAF's Granite construction trucks.
The potential energy savings of hybrid powertrains over conventional diesel engines in refuse collection is considerable, mainly because that sort of stop-and-start duty cycle is precisely where conventional powertrains are least efficient. Parallel hybrid systems are also more efficient in this context than a series system would be, and at a lower cost.
[Source: Volvo via Green Car Congress, Transport Canada, Clean Heavy-Duty Vehicle Conference 2007]
