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.
The electricity that lights our homes and powers our appliances also creates small magnetic fields that are present all around us. Scientists have developed a new mechanism capable of harvesting this wasted magnetic field energy and converting it into enough electricity to power next-generation sensor networks for smart buildings and factories.
Just like sunlight is a free source of energy the researchers try to harvest magnetic fields.
A team led by Penn State scientists developed a device that provides 400 percent higher power output compared to other state-of-the-art technology when working with low-level magnetic fields, like those found in our homes and buildings.
The technology has implications for the design of smart buildings, which will require self-powered wireless sensor networks to do things like monitor energy and operational patterns and remotely control systems.
Researchers designed paper-thin devices, about 1.5 inches long, that can be placed on or near appliances, lights, or power cords where the magnetic fields are strongest. These fields quickly dissipate away from the source of flowing electric current.
When placed 4 inches from a space heater, the device produced enough electricity to power 180 LED arrays, and at 8 inches, enough to power a digital alarm clock. The scientists reported the findings in the journal Energy and Environmental Science.
The scientists used a composite structure, layering two different materials together. One of these materials is magnetostrictive, which converts a magnetic field into stress, and the other is piezoelectric, which converts stress, or vibrations, into an electric field. The combination allows the device to turn a magnetic field into an electric current.
The device has a beam-like structure with one end clamped and the other free to vibrate in response to an applied magnetic field. A magnet mounted at the free end of the beam amplifies the movement and contributes toward a higher production of electricity.
News Source: Eurekalert
