Nov. 29, 2012 at 2:21 PM ET
There are more than 140,000 miles of train track in the U.S., many of them laid across lonely stretches of land with nary a power line in sight. Thankfully, there’s a new gadget to harvest energy from vibrations generated in the track by passing trains to power signal lights and other track-side devices.
The energy harvester could save more than $10 million in trackside power costs in New York state alone, according to its inventor, Stony Brook University professor of mechanical engineering Lei Zuo. It would also reduce carbon dioxide emissions there by about 3,000 tons, he added.
The device converts the irregular up-and-down vibration of a train track to a unidirectional rotation of a generator. The concept is similar to other energy-harvesting devices such as the energy-generating backpack, kneebrace, speed bump and pavers.
The global market for energy harvesters hit $700 million in 2011 and could pass $4 billion by 2021, according to market research firm IDTechEx. Zuo and colleagues have licensed their Mechanical Motion Rectifier-based Railroad Energy Harvester to Electric Truck/Harvest NRG for commercialization.