Europe’s first conference covering the full energy harvesting value chain
In less than two weeks IDTechEx’s inaugural Energy Harvesting & Storage event will take place in Cambridge, UK. The event uniquely features a range of end users discussing their needs for energy harvesters to power small electronic devices. For example, Nokia will present from a consumer electronics products standpoint and Rolls Royce from an engineering one.
The heartland of energy harvesting is replacing single use batteries. Consider the nightmare caused by the 30 billion button batteries made yearly and appearing in everything from our car keys, key finders, clocks, alarms, wristwatches, calculators, children’s toys, games, smart packages, gift cards and more. The number grows as the variety grows and then we have cylindrical batteries in torches, radios, PDAs and so much more. The misery caused when they fail and the tedium of buying and inserting them cannot continue to increase. Wireless sensors in industry can automate manual processes but, as an oil refinery manager said with some vehemence recently, “I am not replacing meter reading with battery replacement.”
Energy harvesters can tackle this problem by using ambient energy to power the devices, for reasons of convenience, cost, safety and reliability. An energy harvesting system consists of the device gathering ambient energy, an energy storage device, if needed, and an interface to the electrical or electronic device being driven. By far the favourite ways of creating the electricity are photovoltaics and electrodynamic (eg dynamo or alternator). They are popular because they are proven, reliable, affordable and provide useful amounts of power. Photovoltaics has no moving parts and it can be very thin, flexible and even transparent. Indeed, there are experimental versions that harvest ultraviolet and infrared as well.
Electrodynamics can provide very large amounts of power and so far it has tended to be more reliable that piezoelectric moving parts – another candidate – which can wear out in wireless light switches, vibration harvesters and so on and produce less power. We see electrodynamics in wind- up lighting, radios and laptops for Africa, in flexing paving, wind turbines and bicycle dynamos. It is even being tested for use on the human heart to replace batteries driving embedded defibrillators, pacemakers etc. No further need to cut you up to change your battery. This does not save the planet but it saves you. Electrodynamic harvesting appears in motion-driven automatic electronic watches.
To look at it more closely, we show examples of needs, solutions and suppliers below, though actual systems often employ only some of these elements. For example, photovoltaics may provide dc power at the right voltage whereas vibration harvesting may provide ac power when dc is needed at a different voltage.
Figure Elements of an electronic device powered by energy harvesting.
Source IDTechEx