Bristol University Wants to Harvest Energy from Vibrations

It now seems that a team of people at Bristol University is hoping to harvest kinetic energy from vibrating household appliances and vehicles. If something like this could actually be done, then it would be able to provide a clean source of commercial electricity within five years time.

The concept, which is already known as energy harvesting, has been around for a decade already. Commercial devices already exist in specialized areas that can do it. One example are the vibrations from industrial pumps. These energy harvesters are currently employed to power sensors that monitor the pumps’ operational condition and are simply powered by the vibration of the pump itself. After all, vibrations are nothing more than energy.

At this point in time, however, these devices can only make use of vibrations within a narrow range of frequencies or number of vibrations per second. They use a spring with a mass on the end to employ a process that is called resonance to amplify small vibrations. This, in turn, enables energy to be extracted from the vibration.

Dr Stephen Barrow, who is currently leading the project, said that just a few milliwatts can power a small electronic device like a heat rate monitor or an engine temperature sensor. However, it can also be used to recharge power hungry devices like a MP3 player or a mobile phone.

The current problem is that if vibration levels are too low, too little electricity is made. This, in turn, makes the device not usable. This situation generates problems in applications such as transport, because the frequency of vibrations changes constantly.