A team of MIT undergraduate students has invented a shock absorber that harnesses energy from bumps in the road, generating electricity and smoothing the ride more effectively than conventional shocks.

The prototype shock absorbers use a hydraulic system that forces fluid through a turbine attached to a generator, with a (6-shock) heavy truck generating up to 6kW on a normal road.

That's enough power to completely replace the alternator in heavy trucks and military vehicles, and in some cases even run extra devices such as hybrid trailer refrigeration units.

Big fuel savings

Shakeel Avadhany says they can produce up to a 10 per cent improvement in vehicle fuel efficiency by using the regenerative shock absorbers, and has calculated that Wal-Mart could save $13 million (£9 million) a year in fuel costs by converting its fleet of trucks.

"Simply put, we want this technology on every heavy-truck, military vehicle and consumer hybrid on the road," Avadhany says.

The students are doing a series of tests with a converted Humvee to optimize the system's efficiency, and plan to have a final, fine-tuned version of the device ready this summer.

They hope that it can be perfected in time for a military vehicle company to secure the expected $40 billion (£28 billion) contract for the new US army vehicle called the Joint Light Tactical Vehicle, or JLTV.