Despite the embryonic market for piezoelectric energy harvesters, there is prolific development of the technology. The development focus is on creating stable, long life, lower cost and smaller piezoelectric energy harvesters. Piezoelectric energy harvesting is still carving its niche with several different types of applications expressing increased interest in the products available.
Although the ceramic nature of piezoelectric materials could have meant limitations due to their brittleness, the development of composite materials in different form factors has helped deal with that problem and has given piezoelectrics flexibility and robustness. Companies like Advances Cerametrics Inc and Smart Material have developed piezoelectric composites in the form of fibers or tubes with support from government grants and research laboratories worldwide. Such material developments have helped popularize the use of piezoelectric materials in energy harvesters because there is less concern about the fragility of the devices in different types of environments.
Source: Advanced Cerametrics Inc.
There is also the approach of companies such as Arveni that occupy a different part of the value chain: Arveni both produces and utilizes piezoelectric energy harvesters in complete products developed for the company's customers. A recent example is their 12 button wireless and microgenerator-powered remote control, which will be showcased at the IDTechEx Energy Harvesting & Storage event in Munich, Germany on May 26-27. The 12-key radio remote is an intermediate step towards a fully functional remote control e.g. for TV applications. The device, which is completely batteryless, uses a powerful piezoelectric microgenerator, which delivers up to 90mW. MicroStrain is developing piezoelectric energy harvesters for health monitoring of rotor blades on helicopters.
Basic Hardware Platforms
Other companies are approaching the market for energy harvesters very differently. Johnson Matthey, for example, provide their customers with 3 basic designs for energy harvesters and work in collaboration with them to develop the rest of the solution, which is completely customizable in order to support their needs.
A slightly different "umbrella" approach is adopted by another company, Microstrain in Vermont, USA. The company designs and manufactures several varieties of micro sensors but in the field of energy harvesting for wireless sensors, the company's EH-Link™ product allows for multi-source input from piezoelectric, thermal, solar and electromagnetic energy harvesting, making sure that the device is performing satisfactorily in a wide variety of environments.
This approach seems to be gathering momentum not only with energy harvesting companies, but also with energy storage ones. Companies such as Infinite Power Solutions and Cymbet also offer energy management solutions (the Infinergy™ and the EnerChip™ ranges respectively), and in these cases, energy harvesting is supported alongside the storage device.
Piezoelectric energy harvesting is maturing, and products based on this technology are being made available. For all the latest innovations in the field as well as the applications and complementary technologies, attend the co-located conferences Energy Harvesting and Storage & Wireless Sensor Networks & RTLS Europe 2010, in Munich, Germany
Top image of piezoelectric fibres source: Sensorsmag
For more read : Energy Harvesting and Storage for Electronic Devices 2009-2019