A Volvo Construction Equipment team from Sweden and South Korea has been quietly working with Finnish company Norrhydro to develop an electro-hydraulic system that promises to drastically cut energy losses and improve fuel efficiency in its excavators.
In a manner similar to common rail fuel systems, all the excavator’s work functions are connected to a hydraulic accumulator via a common pressure rail and two or more pressure lines. These accumulators recover kinetic energy and peak power supply that is normally lost in a conventional system. For cylinder-driven work, “smart actuators” convert hydraulic power to variable force and speed. Energy recovery through the system also boosts the performance and efficiency of the machine’s swing function.
All this energy efficiency translates into a smaller engine and cooling system doing the same work as a larger system, which ultimately results in more work done for less fuel and fewer greenhouse gasses. Additionally, with greater power on tap, cycle times can be shortened, for example when loading a truck, which contributes overall efficiency to the work and cost benefits to the contractor.
Volvo is currently conducting customer trials in the field, and it is expected to accelerate the introduction of the system across Volvo CE’s large excavator platform, with availability coming in the near future. The new electro-hydraulic system is part of Volvo’s e-mobility program to increase fuel efficiency and reach the Volvo’s ultimate goal of net-zero emissions operations.