Refuse Trucks See Noise Levels and Fuel Consumption Cut

An innovative hydraulic stored energy management system, developed and manufactured by Parker Hannifin, is being used by Ros Roca, a leading Spanish producer of refuse trucks, to make significant cuts in operating noise, fuel consumption and emissions. Integrated into Ros Roca’s latest Cross rear loading refuse compactors, which are already use in Barcelona, the new stored energy management system enables diesel engines to idle while rubbish is being compacted, reducing noise levels by 50% and enabling vehicles to be used in the city at night and early hours of the morning. Ros Roca’s latest range of Cross rear loading refuse compactors have been developed to make refuse collection as quick and efficient as possible. Additionally, the company wanted to reduce noise levels so that the vehicles can be used in urban and built up areas outside of normal working hours. This is a problem for most refuse collection vehicles as they need to run diesel engines at speeds of at least 1,000rpm while vehicles are stationary, to drive the hydraulically powered onboard compaction and packing systems at optimum cycle rates without the risk of stalling the engine. As well as increasing noise levels, this also produces higher emissions and consumes more fuel. To address this issue, Ros Roca partnered with Parker Hannifin to develop a new method of powering the various hydraulic mechanisms.

The solution developed by Parker is based on its Stored Energy Management System (SEMS), whereby energy generated during frequent vehicle braking is captured by a hydraulic accumulator. Stored energy is then released via a specially designed conversion and modulation unit to reduce energy to the precise output levels

required by the compacting and packing mechanisms. This is then typically integrated with computerised control, in-cab HMI and conventional ancillary hydraulic components into a system that is easy to install and use. In addition, the accumulator can be charged using an electronically controlled pump, which is attached to a power take-off (PTO) point and that normally operates while the vehicle is in motion to improve efficiency still further. For Ros Roca, this has produced a low maintenance waste compaction and packing system that is almost silent, complying with the latest European noise regulations, and which has resulted in an average drop in fuel consumption and emissions of around 5%.