Engineers Invent Way for Cars to Harvest Energy from Bumps in the Road

Solution in Harvesting Energy from Car’s Suspension

The 255 million cars on the road in the U.S. are accountable for 40% of the fuel consumption of the country, most of which tends to be wasted. An associate professor of mechanical engineering in Virginia Tech’s College of Engineering, Lei Zuo, could have a partial solution – in harvesting energy from the car’s suspension.

He explains that around 10 to 16% of the fuel consumed by the car is in reality used to drive, which is to overcome road resistance as well as air drag and the rest seems to be lost to heat together with other disorganizations. On manipulating smartly, this deficit could be lessened.

He states that for the recovery or generating energy at the time of driving, three major opportunities tend to prevail, namely the waste heat given off by the engine, the kinetic energy that is absorbed at the time of braking and the vibrational energy reduced by shock absorbers. Zuo evaluates that a car’s shock absorbers could be capable of providing between 100 and 400 watts of energy on standard roads and more on rougher roads. By contrast, a normal cell phone call utilises about 1 watt which corresponds to an increase in fuel efficiency between 1 and 5% that could add up to a yearly fuel savings of $13 billion to $19 billion.

Translating–Vertical Vibrations of Suspension/Rotational Motion/Generator-Electricity

His energy harvesting shock absorber operates by translating the vertical vibrations of suspension into rotational motion that tends to turn a generator which in turn delivers electricity to the car’s battery or electrical devices directly, decreasing the demand on the alternator. The method adopted had solved major challenges in harvesting vibrational energy in converting bidirectional, up-and-down motion in the unidirectional motion essential in driving a generator.

A distinctive mixture of gears enables the motion in both directions for the conversion into electricity, needed to double the amount of energy which could be recovered. Zuo associated with the Institute for Critical Technology and Applied Science, clarifies that this invention enables the generator to function at a stable speed thereby reducing the load on the gear teeth, thus making the method well organized, maximizing the quantity of energy recovered.

Zuo together with his students have tested the shock absorber on the roads of the campus. Their present model, that the students had developed utilising off-the shelf components, could harvest around 60% of the existing energy which is a considerable improvement over other designs. Zuo was confident that with accurate components as well as manufacturing the system, they could reach around 85% competence.

Device Retrofitable to Space/Functions

Besides, this, he also stated that the device would be completely retrofittable with regards to space and functions and `could be integrated in the car directly without the need of changing anything in the car’. He along with his team has designed other forms of energy harvesting shock absorbers which include linear electromagnetic as well as hydroelectric absorbers.

Zuo, who had recently received an award for his performance from the Governor’s Commonwealth of Virginia Research commercialization Fund, had stated that he intends to concentrate next on the commercial viability of the energy harvesting system.

He stated that he hopes to speak on the concerns of drivers as well as automakers, who tend to have differed priorities. He further added that `when the same is presented to the drivers, they are asked – how much can one improve the fuel efficiency?’

From the point of view of the car manufacturer’s side, they ask another question – Can one replace the commercial shock absorbers? Can a better suspension performance be given?’ Zuo has commented that he intends tackling both cost as well as performance in the next round of development. Presently the method would not be cost effective for car owners who tend to drive less than an hour or so, a day.

Energy Harvesting – Helpful in Global Energy Crisis

Hence Zuo would be focusing on applications for huge commercial vehicles while working on cost reduction. In order to enhance the performance, Zuo indicated that he wanted to adjust his design by utilising a strategy known as self-powered semi-active control.

A microprocessor tends to sense vehicle conditions and adjusts the suspension settings accordingly and delivers the smoothest ride while harvesting the greatest quantity of energy. Zuo has also been working on two other areas for the purpose of energy recovery in cars, namely waste heat and regenerative braking. Though regenerative braking has already been in use for hybrid vehicles, it only makes up for about 3 percent of the cars on the road.

Zuo desires to develop a method which will probably work for conventional vehicles. The focus of energy harvesting research is often on milliwatts and microwatts and Zuo aims on the methods which could yield hundreds or even thousands of watts. He has commented that `he is particularly excited about the opportunities in large scale energy harvesting which could be helpful in solving the global energy crisis’.