Audi Develops Suspension That Generates Electricity, Boosts MPG

audi develops suspension that generates electricity boosts mpg

The search for better fuel economy takes engineers down weird paths, and the latest plan to wring out extra mileage is no different. It involves an unlikely part of the vehicle — the suspension.

Audi just announced a new suspension system that harvests wasted energy and turns it into electricity, capable of adding juice to a vehicle’s 48-volt electrical subsystem.

The automaker calls the system “eROT” after the electromechanical rotary dampers that capture kinetic energy and store it in a battery. Currently in the prototype phase, the system does away with conventional shock absorbers, replacing them with lever arms connected to a small gearbox and alternator.

“Every pothole, every bump, every curve induces kinetic energy in the car,” said Stefan Knirsch, Audi’s technical development boss, in a release. “Today’s dampers absorb this energy, which is lost in the form of heat. With the new electromechanical damper system in the 48-volt electrical system, we put this energy to use. It also presents us and our customers with entirely new possibilities for adjusting the suspension.”

The lever arm absorbs the motion of the wheel carrier, transferring the power to an electric motor through a set of gears. The motor converts that force into electricity, which is stored in the system’s 0.5 kilowatt-hour battery. That battery has an output of 13 kW, and can feed the vehicle’s generator, leading to a slight improvement in fuel economy.

During an average drive, the system is able to capture between 100 and 150 watts of energy, Audi claims. Rough roads mean greater energy capture, while smooth-as-glass highway jaunts might harness just a few watts.

The system’s benefits are many. Not only does it boost mileage, it would it allow drivers to adjust their ride comfort via the freely programmable dampers. Also, the lack of upright shock absorbers means more trunk space. Audi says the system’s appearance on future vehicles is “certainly plausible.”

The automaker plans to test a beefed-up version of the system in a mild hybrid vehicle next year, with the upgraded eROT expected to boost mileage by 0.7 l/100 km.

[Image: Audi AG]

Join the conversation
3 of 42 comments
  • Lou_BC Lou_BC on Aug 11, 2016

    This would be great on the Ford Raptor.

  • Shaker Shaker on Aug 11, 2016

    I like to say that "efficiency is its own reward", but this tech is a bit over the top - what you want are improvements on the supply side of things - cheap renewable energy should be the focus. Now, if I were on Mars, and needed to get to an old spacecraft many kilometers away to make a miracle escape, I'd be very happy that the electric rover had these "shocks".

    • SCE to AUX SCE to AUX on Aug 11, 2016

      Good call; the Martian could definitely have used these.

  • ToolGuy If you want a new Toyota, plan to buy it in the next 4 years.
  • ToolGuy The real question is - with all the value they add and all the sacrifices they make - do automotive journalists make too little. 😉
  • SnarkyRichard Jesus I double keyed it and J showed up instead of I . No edit function and this site just disappears randomly off of Firefox taking me back to the previous site I was on . Clearly some bugs need to be worked out in this new format .
  • SnarkyRichard J have no desire to get an EV and will never get one . Just give me a manual transmission , a high redline , grippy 4 wheel disc brakes and a two lane highway to slice and dice my way through traffic . No smart phone connectivity needed , just a powerful stereo with 6x9 speakers in the rear to give the classic rock sound of American freedom on the open road . And that's all I have to say about that .
  • Gregtwelve While Sichuan managed to avoid the nationwide energy rationing witnessed in 2021, attributed to a lack of coalWe have plenty of coal. Let's sell them something for a change. And let us not forget that historically the Chinese hate the Japanese for what they did in WW2, so that might have something to do with it.