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“Harvesting Technology”, gathering wasted energy

All of the sudden, the world turns pitch black. Phones turn off and hospitals close doors. The city becomes paralyzed and people return to their primitive lifestyles. Amidst the horror of being disconnected with everything, the battle for survival begins. This is the story of ‘Revolution’, a US drama revolving around a world where electricity has disappeared. Energy is the core of civilization, but resources are limited and energy requirements continue to rise. Thus humanity’s assignment is to find energy sources that are renewable and clean. ‘Energy Harvesting’, the gathering of wasted energy to turn into electricity. Will harvesting be the answer to our assignment?

Green Energy, Improving Safety and Convenience

Energy harvesting is a technology where wasted, useless energy is gathered and converted into electrical energy. The technology can be divided into two main parts, Piezoelectric Generation which uses mechanical energy and Thermoelectric Generation which uses heat. Gathering solar energy from the sun using solar panels is also a form of harvesting. Of these, the category which receives more attention currently is Piezoelectric generation from vibrations, pressure and shock. It shows better efficiency as compared to other forms of harvesting, can be used regardless of the climate and the resources is seemingly infinite. Not just from the sun, wind and rain but also from the vibrations of pipes, the pressure on roads from cars and even electric shockwaves which are all sources. By using piezoelectric materials to generate electricity from various mechanical sources, the converted energy is then stored through circuits.

Energy harvesting can be seen as one of the solutions to powering small wireless devices. Professor Dae Yong Jeon of Inha University’s material science and engineering said “A device that can convert the heat from a outdoor burner into electricity has been released overseas. There is no need to worry about charging phones and batteries during camping now.” In other words, if the technology progresses, various devices can be charged through small solar panels on handbags or through the movement arms and legs. Professor Sang Woo Kim of SKKU’s material science and engineering said “using energy harvesting as the main source of energy for small electric devices won’t be long now. Using the energy resources that are constantly around us, the stable use of devices will be possible”.

Energy Harvesting will also stand out in the safety category. SNU Mechanical and Aerospace Engineering Professor Byeng Dong Youn said “ We can prevent the dangerous situations where losing power or having an empty battery may be problematic. Power can also be provided to dangerous places such as high pressure transmission towers and wireless sensors that may be hard to reach.  Professor Dae Yong Jung said “we can prevent the hassle of regular surgeries for replacing batteries in artificial hearts by powering them with auxiliary power from heartbeats and body heat.”

[energy harvesting] refers to harvesting wasted energy from the environment to convert it into useful electrical energy. The main sources for harvesting are vibrations, human movements, light, heat, electromagnetic sources and others. The Seeback Effect which shows that current is generated in a closed circuit from the difference in temperature of different metals joined together, or the Peltier effect which shows that heat is generated on one side and absorbed from the other when current flow is reversed; Thermoelectric Effects. The Piezoelectric effect where current is produced through pressure. Energy harvesting is a technology which encompasses all these effects.

Energy harvesting was selected as one of the top 10 promising technologies by MIT, along with Popular Science (US Science Magazine) picking it as one of the 45 innovative technologies to shake the world. Various countries are holding various researches to master this technology first. In Japan, an electricity generating floor was developed which collects pressure and vibration energies from cars and people passing over it. The saved electricity is used to power the street and traffic lights.

A research team from Georgia Tech has managed to increase the surface area of a material that can collect energy, enabling it to power hundreds of LEDS. Within the nation, technology that collects energy from static electricity with graphene and fabrics that can power wearable computers have been developed. It is now possible to build touchscreens that power themselves and displays that can be powered by the wind.

Professor Byeng Dong Youn’s team has developed the ‘EH Skin” that collects energy from the vibrations of the outdoor air-conditioning unit which has LEDs and temperature sensors attached to it, enabling consumers to check the temperatures remotely. Professor Youn said “We can collect more energy from the KTX or the wings of planes. We can greatly reduce the cost associated with replacing the batteries of wireless sensors and even monitor areas where installing sensors were not possible due to power issues. Professor Sang Woo Kim’s Team developed a technology that can charge cellphones from the friction created by waves and vibrations from sound. Energy Harvesting will likely continue to be developed to solve the earth’s energy problem. IDTechEx (Global Research Company) predicts that the piezoelectric energy harvesting markets will reach the values of 145 million dollars by 2018 and 667 million by 2022. It can be use in sectors ranging from large scale generation devices to small Nano-machines, backup power for medical devices, secondary generator for cars, wearable devices, powering ubiquitous sensor networks and even artificial hearts. It is currently being heavily researched be make it the new power source for electronics of the future.

Dr Young Bok Ham from KIMM said “Energy harvesting is a sector with infinite potential. Research institutes and schools need to start pondering about highly efficient materials, structures circuits and design technologies and industries should readily invest in the technology” Professor Sang Woo Kim hopes to set up a new energy market for User Created Power (UCP) to allow consumers to power their own devices and expand the low-carbon green energy market.


Min Yeong Lee tia@joongang.co.kr | 제380호 | 20140704  

Article: http://sunday.joins.com/article/view.asp?aid=34605