“Regenerative” is one hot technology buzzword at the moment, with even Formula 1 race cars using regenerative braking to bring some eco-friendliness to the sport. And MIT researchers have worked out a new way to include regeneration into your auto–by designing regenerative shock-absorbers.
It’s a classically simple and brilliant piece of thinking: As your car bobbles along the pits and troughs of a normal highway ride, the body rides up and down on its hydraulic shock absorbers–neatly insulating the people inside from the uneven road surface. But all that pitching up and down kinetic energy is currently just thrown away as heat by existing shock designs.
The MIT team realized that this is a perfect power-generating opportunity that’s simply going to waste, especially when you look at how often and how far a heavy goods vehicle will swing up and down on its shocks as it hits a bump.
As a result, they’ve designed a new shock that incorporates a tiny turbine. As the shock is compressed or extended (when the attached road wheel hops over a lump in the pavement) the hydraulic fluid inside is forced past the turbine. That acts to both generate electrical power, and damp the oscillation of the shock absorber. Since the system has some electronics that control the degree of damping in real-time it can even result in a smoother ride for the vehicle. With its Eco-friendliness and smoother this invention seems almost too good to be true.
The MIT team formed the Levant Power Corp. to commercialize the product, and it may even turn up on the future Army “Joint Light Tactical Vehicle,” should the bidding go their way.
Tests have shown the system has pretty remarkable power-generating possibilities: The team tested a heavy 6-wheel truck, and discovered that a journey on an average road can generate up to 1kW. That’s about enough to replace the alternator in the engine that generates electrical power for the truck at the expense of using some of the energy gained from burning gasoline. The team’s calculated it may even save a company like Wal-Mart $13 million a year in fuel if it converted its conventionally-fueled truck with the system.
In a smaller personal vehicle, the power gained from these smart shocks wouldn’t be quite so significant. But if it were to be combined with a regenerative braking system, and other alt-fuel sources like a solar-panel roof, then all-electrical vehicles may be able to be even more energy efficient. And if President Obama’s plans for the smart electrical national grid really get underway, regenerative shock absorbers are exactly the sort of technology that may result in electric vehicles actually returning spare energy to the grid while they’re parked.