The field of piezoelectricity is one that has been around for decades now but remained unexplored to a large extent. Piezo, gotten from the Greek word, means to squeeze or press, and energy is generated through this method when certain materials are exposed to mechanical stress.
In recent times, we have seen a huge leap from what the field used to be, and we have seen advanced technology that brings about energy generation via human locomotion, thermoelectric materials, and even internal organs. We shall go into detail in this article and uncover some other ways by which smart devices can use their owners as sources of electrical energy.
To start with, some of the major sources of energy in the body are delineated here.
The Human Blood
For proper functioning, our cells are continually supplied with chemical energy, and recent studies show that the energy supplied can serve us in more ways than we imagined. We have witnessed the emergence of enzymatic biofuel cells (EFCs) in recent years and these small devices have the capacity to generate electricity by breaking down the chemicals in the body.
This battery has been tested on living creatures and when one of such was developed in 2012, it was implanted in the abdomen of a rat, generating 40 microwatts in return. This power was used for an LED and a digital thermometer.
This is another viable alternative that can be used to tap the body’s potential without going internal. How does it work? Well, the human sweat contains a profuse amount of lactate, a compound that can be used to generate electricity. Similar tests have been carried out on humans and the same stellar results have been recorded.
The major drawback to using sweat as a source of energy for smart devices is that people do not usually sweat often, hence, its use might be restricted this way.
Considering the fact that we just spoke about sweat being limited, you probably think that tears are even worse, right? Well, this is not necessarily the case. The cornea is usually kept moist via a film of basal tears (as opposed to the psychic tears that are produced when we cry). The basal tears contain lactate, glucose, and ascorbate and this is an excellent source of fuel for the same EFCs.
Another advantage of using tears as a source of energy is that there’s already an existing platform on which the energy can be harvested; the contact lens. Even though the concept for tears is still in its nascent age, we anticipate more from it in the future.
Now that we have seen the common sources, let’s move on to the most groundbreaking discovery in terms of smart devices and energy generation; TENG Devices
The Triboelectric Nanogenerator
Researchers, for a long time now, have been exploring other viable solutions for future-state electronic devices and the Triboelectric Nanogenerator (TENG) has been deployed to that end. According to scientists at the University of Surrey’s Advanced Technology Institute, we are on the verge of technological advancement such that smart devices can use their owners as a source of energy. TENG devices are able to utilize the energy from sources like wind, wave, and even vibration of machines in the surrounding.
What is TENG?
This is a type of energy harvesting device that exploits the contact between different materials just to generate electric current. The nature of the materials varies as they could be organic, inorganic, or a mix of both. Their operation is governed by the triboelectric effect, and this effect explains how certain materials are electrically charged when friction occurs between the material and another material.
Researchers have now come together to produce an interactive guide that outlines the process by which energy harvesters can be constructed. The TENG power transfer equation, as well as TENG impedance plots, have also been proffered.
The lead researcher on this project, Professor Ravi Silva, has touted the potential impact of TENG, as they are ideal for powering wearable devices, self-powered electronics, and other miniature devices. In essence, TENG could be the radical technology that facilitates the growth of the internet of things.
The rate at which technology is advancing is quite rapid and it should not come as a surprise if TENG devices become ubiquitous in a short while. Research and development, however, is still in progress to ensure that they do not adversely affect the health of humans.