A car's suspension is designed to absorb kinetic energy from driving over bumps so that they are not transferred to the cabin.
The thing is, that energy has to go somewhere, and at the moment it's mostly wasted as heat. However, Audi has targeted this lost energy with its new suspension setup that converts the heat to electricity, which can then be used to charge batteries.
This new system, which has the rather unfortunate acronym 'eROT', involves using a lever arm that absorbs the movement of the wheel carrier. It is attached to a series of gears that transmit that movement to an electric motor to generate electricity.
Road surface largely dictates how much electricity is generated. Based on testing, Audi reckons an average of about 100 to 150 watts on German roads. That's from three watts on newly surfaced autobahn to 613 watts on rubbish side roads. We can expect good returns in the UK, then...
The advantage of charging batteries with this system is that there's less reliance on the engine to do the job. This sort of kinetic energy recovery system has seen the engine become less vital to battery top-up, and that means better fuel economy.
The system requires Audi's 48 volt 'substation' battery setup, which is currently only fitted to the SQ7. However, it is planned to be fitted to more models soon, so this suspension technology might not be too far off.