Comparison of regenerative braking technologies for heavy goods vehicles in urban environments

One way to reduce the carbon dioxide emissions of heavy vehicles is to install regenerative braking systems. These capture the kinetic energy of the vehicle during braking and store it, in order to feed it back into the drivetrain during acceleration. It is not clear, however, which of the many available technologies should be used to implement this regenerative braking. This report explores the different possible energy capture and storage technologies for regenerative braking, including electrical, kinetic, hydraulic and compressed air. The basic systems are plotted on a selection chart, and an optimal selection methodology is used to aid in the selection of the lightest and smallest system for regenerative braking. The results of this comparison and selection show that hydraulic energy storage is likely to be 33% smaller and 20% lighter than the closest electrical counterparts and is therefore a logical selection for regenerative braking on the trailers of heavy goods vehicles.