Harnessing Energy Through Human Movements
Alternative energy choices have been, and continue to be, an emerging area of research. Inventions regarding the use of wind, solar, wave and biomass energies have transformed how consumers power their lives. These forms of alternative energy have impacted how we power our homes, run our cars and even charge our phones. With such a wide variety of alternative energy sources available, it is of no surprise that there are continuous new developments in this sector. The newest competitor seeks to harness the energy of bending motions made by humans to generate electricity.
MIT Professor, Ju Li, alongside four graduate students, has released research describing a new method of harnessing energy that is based on the bending of a sandwich of metals consisting of polymer and metal sheets. Old systems of harnessing energy from small movements that are similar to the one researched by Ju Li relied on the concept of friction to generate electricity. This new idea of harnessing power acts more like a lithium ion battery and focuses on taking in mechanical energy and transforming that energy into electricity as its output. When the sandwich of polymer and metals is bent, even a slight amount, the pressure difference that is produced causes the lithium ions to interact with the polymer to produce electricity that can be used to power other devices.
In early 2015, a technology similar to the one researched by Li was developed. German researchers developed a shoe that harvested power from walking. BBC News reported on how the shoe utilizes the movement of walking to generate electricity, “There are two separate devices: a “shock harvester” that generates power when the heel strikes the ground and a “swing harvester” that produces power when the foot is swinging”. Limitations are present though, as not enough energy is able to be generated through this process to even charge a smartphone.
Similar research regarding generating electricity by walking was also experimented with in 2008. Specialized pavement was placed in the world’s busiest pedestrian area of Shibuya train station crossing in Tokyo, Japan in attempt to generate electricity by harnessing the vibrations that resulted from 900,000 people stepping on it daily. The same limitation was present though as not enough electricity was generated to produce efficient power.
This new development in converting human movements into electricity is more powerful though because of its focus on the conversion of mechanical energy into electricity. Wu Wenzhuo, an industrial engineering assistant professor at Purdue, predicted the future implications of this emerging energy, “…the output current from the demonstrated device is very large, with a long pulse duration. This is very important for practical applications, since most other mechanical energy harvesting methods suffer from the issues of small current output with short pulse duration”. The large output potential from harnessing this energy could transform wearable devices, robotics, and other emerging technology. With so much movement occurring on a job site, implementing this technology in the construction industry could result in more efficient and economical operations for companies.