MIT Invention Harvests Energy from Vibrations

Bridges, overpasses, walkways…we’ve all felt the rumble or the shaking as people and vehicles cross these structures. Slightly nerve-wracking and sometimes annoying, is there any real use for these vibrations? After all, it is a form of kinetic energy. MIT has thought outside the box yet again to rig up a miniature energy-harvester that can pick up the low-frequency vibrations produced by a bridge and convert them to electricity. That electricity can then power wireless sensors that measure the strength and condition of the bridge. These wireless sensors are being used more and more to monitor everything from oil pipelines to pollution to factory machines.

Batteries in these sensors need to be charged every so often, even though they have become more efficient over time. Wouldn’t it be nice to do away with batteries all-together, or let the device charge the batteries itself? We may be on the way there. Here’s how the MIT blog put the invention (full, more technical explanation here):

Researchers at MIT have designed a device the size of a U.S. quarter that harvests energy from low-frequency vibrations, such as those that might be felt along a pipeline or bridge. The tiny energy harvester — known technically as a microelectromechanical system, or MEMS — picks up a wider range of vibrations than current designs, and is able to generate 100 times the power of devices of similar size. The team then put the device through a series of vibration tests, and found it was able to respond not just at one specific frequency, but also at a wide range of other low frequencies.

If the devices can be made to produce 100 microwatts (the current design produces 45 microwatts), a system of smart sensors monitoring an oil pipeline for leaks would be able to talk to each other without batteries simply by using the energy from vibrations produced by oil flowing through the pipe.[Image]