Until the 1970s kerbside garbage collections were carried out by hand by operators on foot running with conventional rear-loader compactor trucks. When kerbside recycling collections were introduced in the 1980s a similar system of manual collection was also used. Operators separated the contents of open crates putting materials into individual compartments in the collection vehicles. At this time mechanical collection of garbage in wheelie bins by side-lifting vehicles operated by only the driver became more common.
Although the vehicles were more expensive to acquire, they saved on staff costs and reduced occupational health and safety risks. With the advent of materials recovery facilities that separate recyclables at a central facility, recyclables were also collected ‘comingled’ in wheelie bins rather than in crates. The vehicles used were the same design as those used for garbage. Invariably they were diesel powered.
Since those early vehicles, there have only been small advances in vehicle design, most notable in the area of recycling collection. Vehicle manufacturers have designed lifting arm and hopper mechanisms that reduce the vigour with which recyclables are collected and distance that they have to fall from the bin into the collection vehicle. These advances have been nullified somewhat by the ability of drivers and fleet operators to override these mechanisms.
The most recent changes in collection vehicle design have revolved around the fuel they use. In the quest for zero-emissions, electric and hybrid-powered vehicles are coming onto the market. Traction batteries provide continuous power over longer periods and are used for transport and industrial applications. Despite improvements in traction battery design, electric vehicles still cost more to buy, take longer to refuel and have a limited operating range.
Volvo has developed a hybrid 6 x 2 rear steer truck chassis, fitted with a Geesink Norba ‘plug-in’ hybrid compaction refuse collection equipment. This means that there is a hybrid power system for the chassis and another for the compactor and bin lifters. The compactor and lifter hydraulic power system had an independent battery pack that is primarily charged overnight and topped up by the truck engine. This then powers the hydraulics. Even when the truck is stopped there is enough power to make up to 1000 bin lifts and enough compaction cycles to last an eight hour shift without any additional charging from the engine.
The hybrid chassis power is more useful in city streets where in slow speed stop/start situations the internal combustion engine is automatically shut down, and the drive comes from the electric motor powered by the battery pack. If required, pressing the accelerator will automatically start the internal combustion engine and engage drive. The diesel engine and an electric motor can alternate in use or be used in tandem. The electric motor is designed to be used when the vehicle is going slow or accelerating and is said to cut fuel consumption by 15-20%. An extra battery with a plug-in recharging facility to power the ancillaries also cuts an extra 10-15% off the fuel consumption.
The vehicle makes virtually no noise while in operation, emit no exhaust while under electric power and have low carbon emissions. The plug-in compactor system can be fitted to existing conventional diesel truck chassis.157