Researchers from Penn State have developed a device that can turn wasted magnetic energy from household devices into electricity that can power the next generation of sensor networks for smart buildings and factories. The device takes advantage of a free energy source that is already present in cars, homes, offices and more. The new device provides 400% higher power output compared to other state-of-the-art technology with low-level magnetic fields.
A team of scientists has developed a new mechanism to harvest stray magnetic fields all around us and convert the energy into useful, usable electricity. Source: Kai WangSmart buildings require self-powered wireless sensor networks to monitor energy and operational patterns and remotely control the building's systems. Energy efficiency in buildings is improved with the automation of many building functions. Sensors make this automation possible.
The device is 1.5 in long and paper-thin. It could be placed on or near appliances, lights or power cords with strong magnetic fields. The device is made of two materials sandwiched together. The first material is magnetostrictive, which converts the magnetic field into stress. The second material is piezoelectric, which converts stress into an electrical field. This combination allows the device to turn a magnetic field into energy. The device is a beam-like structure with one end clamped and the other end free to vibrate in response to the magnetic field. A magnet on the free end amplifies movement and contributes to higher production in electricity.
When placed four inches form a space heater, the device produced enough electricity to power 180 LED arrays. At eight inches away, it generated enough energy to power a digital alarm clock.
A paper on the new device was published in Energy and Environmental Science.
