02-06-2012, 05:00 PM
Energy Harvesting Shock Absorbers
Energy Harvesting Shock Absorber, June 2011.pdf (Size: 359.46 KB / Downloads: 265)
Transportation accounts for 70% of oil consumption in Unites States. However, only 10-16% of the fuel energy is used to drive the car - to overcome the road resistance and air drag. People have been seeking ways to improve the miles per gallon (mpg) of vehicles; regenerative brakes and hybrid vehicles are successful examples. Recently, Professor Lei Zuo at Stony Brook University have been examined another important energy loss mechanism - vehicle vibration and designed retrofit regenerative shock absorbers with high energy density that recovers a vehicle's vibration energy. This technology has the ability to continuously recover a vehicle's vibration energy that is otherwise dissipated due to road irregularities, vehicle acceleration, and braking, and further use the energy for better suspension control.
We estimated that for a middle-size vehicle, 100W, 400W, and 1600W of average power is available for harvesting from the regenerative shock absorbers while driving on Class B (good), C (average), and D (poor) highways at 60 mph, which is comparable with the car alternators (500-600W). And the energy potential for trucks, rail cars, and off-road vehicles is on the order of 1kW-10kW. This represents a potential of 1-4% fuel efficiency increase in conventional cars and up to 8% for hybrid vehicle.
The team at Stony Brook University has designed and patented both linear and rotational electromagnetic energy harvester to replace the traditional shock absorbers and make the vehicles suspension dual functional: mitigating vibration and electricity-generating. A unique configuration using both radial and axial magnets is used in the linear harvester design, and a compact motion magnification mechanism is employed in the rotational harvester. Retrofittable prototypes with high energy density have been developed and tested in our lab with the funding support from New York State Energy Research and Development Authority (NYSERDA). We expect 1-2 years of recoup time for the implementation in trucks and service vehicles, and 3-4 years of recoup time for typical passenger vehicles. Our work has been highlighted by several public news media including, PhysOrg, IOPscience, New York Times, and MIT Technology Review. We won the prestigious R&D 100 Award by the R&D Magazine in 2011, and the Winner of Best Technology Development of Energy Harvesting by the conference of Energy Harvesting and Storage USA, Cambridge MA, November 2010.