Power From Low-Frequency Vibrations

Generating power via piezoelectrical processes has always been limited by the size of the device and the frequency generated, but researchers at Singapore's Agency for Science, Technology and Research (A*STAR) claim to have found a way to harvest enough power from low-frequency vibrations to power small electronics.

The A*STAR Institute of Microelectronics (IME) says it can power small devices indefinitely, and the energy harvester can continuously convert low-frequency vibrations across a wide frequency into electricity. The aluminum nitride harvester has a power density of 1.5 x 10-3 W/cm3 cubed, and can generate the same amount of energy as three commercial implantable batteries over a 10-year period.

"Our design strategy exploits the coupling effect between the Vortex shedding and Helmholtz resonating in order to enhance the Helmholtz resonating and lower the threshold input pressure. By transferring the low frequency input vibrational energy into a pressurised fluid, the fluid synchronizes the random input vibrations into pre-defined resonance frequencies, thus enabling the full utilization of vibrations from the complete low frequency spectrum."  —Dr. Alex Gu, Technical Director, IME Sensors and Actuators Microsystems Programme

This type of power source could feed small sensors and other devices, and do so more reliably than previous piezoelectrical systems. You can read more about it in the original press release here.

Source: Gizmodo