BOSTON – Researchers from the Massachusetts Institute of Technology have invented a device that operates without a battery or a plug — and sans dirty energy.
“We have provided an example of a battery-less sensor that does something useful, and shown that it is a practically realizable solution. Now others will hopefully use our framework to get the ball rolling to design their own sensors,” study lead author and Massachusetts Institute of Technology graduate student Daniel Monagle said in a story published by MIT.
Since the self-powered sensor gathers energy from its environment, the experts envision its use in places that are difficult for people to get to, like the “inner workings” of a ship’s engine. There, it could monitor temperatures during operations, according to the researchers.
These temperature sensors can run on ambient energy, which is created from the magnetic field surrounding a wire that carries electricity. As an example, the MIT team said the sensor could be clipped to the wire that powers a motor, and it would then draw ambient energy to operate.
Instead of a battery, the tech uses simpler capacitors, which the experts said can store energy from the electrical field. These are needed for the sensors to operate on a cold start.
The University of Calgary lists several types of ambient energy sources, describing them as natural forces that are seldom used by people. Ambient power is generated around us without our help. Calgary noted that tidal forces, sunlight coming in a window, and even a cool breeze are other types.
Scientists elsewhere are learning how to harvest energy even when low-speed air passes over water droplets. Utilizing more of the ambient energy around us could be a unique way to help transform our energy system, including small devices like sensors that currently need batteries or wires.
Interestingly, MIT’s framework doesn’t have to be limited for use inside a ship’s hull. The design can draw power from other ambient sources, including vibrations and sunlight, per the lab report. As an application example, the researchers envision groups of sensors in factories gauging crucial metrics at a lower installation cost.
“You might not even have the luxury of sending out a technician to replace a battery. Instead, our system is maintenance-free. It harvests energy and operates itself,” Monagle said in the MIT story, regarding certain sensor applications.
The team plans to continue researching the tech to harness ambient energy even more efficiently.
John Donnal is an associate professor of weapons and controls engineering at the U.S. Naval Academy. He isn’t involved with the research, but he is following the progress — and he likes what he is seeing.
“Energy-harvesting systems like this could make it possible to retrofit a wide variety of diagnostic sensors on ships and significantly reduce the overall cost of maintenance,” he said in the MIT report.
