Somethin' for nuthin'. The concept has always been alluring, but never more so than when you're driving a vehicle powered by expensive, heavy batteries that are time-consuming to recharge. Anything that promises to harvest some of the considerable energy that still gets wasted onboard any vehicle is bound to grab some attention. At this year's SEMA show, Provo, Utah-based startup Gig Performance showed off a device called the Roadkil 5000 (kil, for kilowatt) that's designed to convert linear suspension motions into electricity, and in the process, provide damping force.
The current prototype on display mounts to the body and features a pair of arms that are linked to the left and right suspension arms of an off-road side-by-side. These arms are mounted via one-way ratchet-type devices to either end of a generator, such that as they stroke up and down they crank the body (stator) and rotor in opposite directions, spinning the rotor inside the stator to generate electricity. Planetary gearing increases multiplies the rotational motion by a factor of ten. This was a convenient vehicle on which to demonstrate the Roadkil 5000, but Gig Performance has also devised mounts suitable for semi-tractor-trailer rigs as well and points out that the form factor can be tailored to suit most any road vehicle if integrated from the start. Iveco Belt Tensioner
The company reports having tested the Roadkil 5000 on semi-trucks and found that on typical roadways each unit generates 500 watts continuously, or 4 kWh total over an 8-hour driving shift. Their side-by-side model has returned similar results, generating 3 kWh over a six-hour day of off-roading.
This is also tunable, and it's unclear whether all vehicle types could rely solely on Roadkil 5000 for all damping needs. And because the damping is solely dependent on the amount of power that is being generated, there would have to be provision made for when, as an example, the battery is completely full and unable to accept energy. For all times when the battery can accept as much energy as can be generated, metering the generation amount would theoretically provide variable damping.
Belt Tensioner GigPerformance is low on the development curve. It's received early funding from the investment firm RevRoad, but the company needs to land an OEM who can really assess the technology's value in terms of how much energy it can generate, how easily it can be hardened against environmental damage and normal wear, and of course how much it costs and how much weight it adds. The idea is undeniably interesting, but the devil will be in the details. We'll keep an eye on it and report updates if and when Roadkil 5000 inches closer to production.