Sustainable energy takes many forms and has many possible futures, but nature itself holds one principal law at its core and it is this very immutable law that engineers at Duke University are looking to tap into in order to harness and utilize more efficient and naturally occurring energy. The law in question is simply this: Energy itself can never be either created or destroyed, it can only be changed into one form or another. The engineers, therefore, are investigating ways in which the energy from the motions of everyday life can be harnessed and turned into energy sources.

In the normal course of events most of the energy that we create and use often ends up being dissipated into heat or transferred kinetically into our surroundings without our knowing, while harnessing these circulating and constantly dissipating energies is becoming a growing focus for future energy developments. A larger scale application of these principles would apply to the huge wind farms and turbines that are becoming a more and more common site, whilst utilizing the kinetic energy produced by the simple and everyday activity of walking to provide a power source for small portable electronic devices is a smaller-scale yet potentially even wider-reaching project.

Although the precise amount of energy that people generate during the course of their everyday activities has never been calculated it is very likely that, taking into account all of our untapped and unsourced actions, we are wasting a huge amount of potential energy by not utilizing our own bodies to the fullest and channeling the energy we normally release into other collection devices. While we currently have the technology to harness some of this power the major current problem with providing effective devices to do so is that the devices in question only currently perform well over a narrow range of frequencies and are therefore somewhat limited. As a result the force of motion necessary to generate sufficient power needs to be reasonably constant, so walking for instance would need to be undertaken at a constant pace in order to be effective and this is not always possible due to unalterable environmental factors.

The Duke engineers postulated that the ideal device for utilizing such energy would be one capable of converting a wide range of vibrations as nature itself does not work in a single frequency. The engineers found that through tuning the bandwidth of experimental devices with magnets this new non-linear method was far more successful than linear devices. Through the use of these magnets the engineers were able to effectively ‘tune’ the interactions of the device with its environment and the energy circulating there in, and by such tuning mechanisms the device is able to trap and produce electricity over a wide range of different frequencies which best mirrors situations found in everyday life. Such self-sustaining systems have a potential wide range of applications that, with proper ambition and development, would be limited only by our imagination.

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