Stony Brook scientist seeks to harvest kinetic energy
Lei Zuo, assistant professor in the Department of Mechanical Engineering at Stony Brook University, invented a device to harvest energy from vibrations of passing trains to fuel lights and gates at rail crossings. (Sept. 6, 2012) Credit: Heather Walsh
Some scientists look to the sun and wind to solve the world's energy problems. Lei Zuo seeks answers along rutted highways and desolate railroad tracks.
The Stony Brook University professor invents products to generate electricity from vibrations all around us. He has licensed technology to a California company for an automotive shock absorber that produces wattage from bumpy roads. He designed a contraption to derive electricity from swaying skyscrapers. And he built a device that harnesses the rumble of passing trains to power crossing gates in the middle of nowhere.
"There is a lot of wasted energy out there," said Zuo, 38, an assistant professor of mechanical engineering.
Tapping into energy
Zuo is a part of a small but growing cadre of scientists and entrepreneurs who see big economic and environmental potential in harnessing untapped kinetic energy. To them, nearly anything that moves could provide a few extra watts and, they hope, give rise to a multibillion-dollar industry that makes products more efficient and curbs the need for fossil fuels.
The global market for such devices is expected to hit $700 million this year and rise to $5 billion in the next decade, according to market research firm IDTechEx.
Here on Long Island, officials want to capture some of that growth. They are banking that developments by Zuo and his fellow researchers at Stony Brook, Brookhaven National Laboratory and other institutions will spur a new generation of technology companies to fill the vacuum left by the region's waning aerospace industry.
This vehicle shock absorber harnesses the energy of vibrations and recycle it back into the vehicle as electricity. R&D magazine recently honored Lei Zuo, an associate professor of Mechanical Engineering at Stony Brook University, with an R&D 100 award for his invention. The regenerative shock absorber for cars can harvest over 100 watts from vehicle vibrations during normal dirving conditions. Zuo ia a member of the team at the Advanced Energy Technology & Research Center at Stony Brook University. (July 4, 2011) Credit: Stony Brook University
"This is precisely the type of activity that we need to boost our economy," said Mark Lesko, who this week becomes executive director of Accelerate Long Island, an effort to nurture local start-ups.
Predicting the economic potential of Zuo's devices is difficult. But similar ideas have hit pay dirt. Toyota and Honda, for instance, use technology akin to his shock absorber in the brakes of hybrid vehicles.
The concept, called energy harvesting, flows from century-old methods of tapping movements of wind and water to power electric generators. Like matter, energy cannot be created or destroyed; it can only be converted to another form. As technology races ahead, businesses and researchers are finding new ways to put that old principle to use.
In Rochester, N.Y., for example, a start-up company, Energy Harvesters Llc, is developing boots with generators embedded in the heel to produce power with every step. One hour of walking is enough to charge a smartphone.
In Manhattan, Uncharted Play Inc. has developed soccer balls that generate electricity as they are kicked. The balls, manufactured by Precision Assembly Technologies Inc. of Bohemia, are distributed to children in Third World villages where soccer is ubiquitous and electricity scarce.
And at the University of Michigan, professor Daniel Inman is experimenting with ways to power pacemakers with beats from the hearts they regulate. At the request of a government spy agency, he also once invented a vibration-powered tracking device that could be furtively affixed to a car. The agency, which Inman declined to name, didn't want to sneak up on vehicles a second time to change batteries.
Harnessing vibrations
Companies have long used energy harvesting in consumer products. (Remember those bicycle lights that grew brighter as the pedals turned faster?) Now they have radically improved the technology and are implementing it seemingly anywhere vibrations abound and replacing batteries is onerous. MicroStrain Inc. of Vermont, for instance, has developed energy-harvesting sensors to warn of impending cracks on bridges, helicopter blades and airplane wings.
"Energy is finite and being smarter about how we use it even on a micro scale can help," said Todd Nordblom of MicroStrain, which agreed last month to be bought by Lord Corp. of North Carolina.
Most scientists see energy harvesting as a way of contributing modestly to overall electric usage. Zuo, however, has bigger aspirations.
Zuo grew up on a farm amid the rice fields of central China, about 500 miles west of Shanghai. As a child, he dismantled and rebuilt clocks. At 13, he built a small wind turbine from scratch to power a radio.
"I am curious about things," said Zuo, who lives in Nesconset with his wife, a software engineer, and their son, who turns 2 this month.
After graduating from Tsinghua University in Beijing, Zuo moved to the United States at 25 and enrolled in the Massachusetts Institute of Technology for his master's degree and doctorate. He arrived at Stony Brook in 2008.
His idea for powering railroad gates came a few years later, while riding a train to Albany. As the rolling hills of the Hudson Valley flashed by out the window, Zuo felt his seat vibrate. Bells clanged at a crossing, and red lights flashed. Something inside Zuo clicked.
"Maybe we can do something with this," he said to himself.
Back at his lab, Zuo designed a roughly 2-foot-long device that could be mounted on a railroad track. The vibrations of passing trains would set in motion a series of gears, turning the generator's crank. By Zuo's calculation, it could produce as much as 200 watts: enough to power crossing gates and lights. He has approached the Metropolitan Transportation Authority about testing the device, but the agency has not committed.
Zuo's shock-ing success
Zuo's first significant energy harvesting success was the shock absorber, which he says generates as much as 400 watts on a smooth highway. Add potholes, and the potential output jumps above 1,600 watts. All told, the device can take enough strain off the battery and alternator to boost fuel efficiency by 2 to 8 percent at 60 miles per hour, Zuo said.
Last year, his shock absorber was named one of the top 100 innovative products of the year by R&D magazine. He has licensed the technology to Harvest Energy Inc., of Newport Coast, Calif.
Zuo's goal is moving energy harvesting beyond being an ancillary power source. He wants to fuel the grid. For that, he is turning to the sea and skyline.
Some skyscrapers have massive weights inside their upper floors. The devices, called tuned mass dampers, sway like pendulums, or roll back and forth, to counteract the wind and stabilize buildings. They weigh hundreds of tons. That's serious potential energy.
Zuo has designed a system to work in conjunction with dampers to make skyscrapers even more stable. In addition, he said, it could generate enough power for upward of 60 homes. He has yet to test the system, partly because of building codes.
Zuo's latest interest is the ocean. Businesses have tried for years to generate electricity from waves, but with little success. Zuo is looking for funding to develop his idea to outfit a buoy with a generator, hoping to harness the most powerful source of movement on Earth.
