A Theoretical Study of Mechanical Energy Harvesting from Vehicle Suspension

When a car travels over an uneven road, its suspension moves up and down to reduce the effect of the road on the passengers and the vehicle. Some of the mechanical energy involved in this motion is normally lost as heat in the shock absorber. This paper presents a theoretical investigation of whether some of the mechanical energy involved in vehicle suspension movement could potentially be converted into useful electrical energy. The study focuses on the elastic potential energy stored in a suspension spring and uses the equation ΔE = 1/2 k(x₂² − x₁²) to estimate the change in stored energy. Using an assumed spring constant of 30,000 N/m and a displacement change from 0.02 m to 0.07 m, the model gives a calculated energy change of 67.5 J. Hypothetical conversion efficiencies are then used only to illustrate how much electrical energy might result from different levels of conversion. The study is theoretical and does not report physical experiments or measurements from a real vehicle. It also discusses existing research on regenerative shock absorbers and the limitations that would need to be considered in a practical system.