A South Korean research institute (ETRI) has invented a device that can harvest free energy from the environment and use it to power electronic devices.
The invention uses piezoelectric micro energy harvester that can convert tiny vibrations in the surrounding into electrical energy. Such vibrations may be a result of natural causes like wind or human activity such as vehicular movement, operation of machines etc.
Since the energy in these vibrations is tiny, it’s important to have high energy conversion efficiency. So the micro energy harvester is finely tuned to the frequencies of the vibrations.
Since different environments would have different spectrums of vibration frequencies, the invention uses an array of micro energy harvesters each tuned to a separate band of frequencies. This allows the micro energy harvesters to function and provide energy independent of the environment.
By connecting together, a sufficiently large collection of such micro energy harvesters, devices like smart phones and tablets can be powered without needing a battery.
Publication number: US 9293689
Patent Title: Method of manufacturing a piezoelectric micro energy harvester
Publication date: 22 Mar 2016
Filing date: 29 Oct 2013
Inventors: Chi Hoon Jun; Sang Choon Ko; Jong Tae Moon;
Applicant: Electronics and Telecommunications Research Institute