Zervos (right) the technical analyst at IDTechEx which holds its co-located conferences on Energy Harvesting and Storage & Wireless Sensor Networks & RTLS Europe in Munich, Germany in May.

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  (left) Advanced Cerametrics Inc  and Smart Material (right) have developed piezoelectric composites in the form of fibres or tubes with support from government grants and research laboratories worldwide. Such material developments have helped popularise the use of piezoelectric materials in energy harvesters because there is less concern about device fragility in different types of environments.

Product approaches
There is also the approach of companies such as Arveni that occupy a different part of the value chain: Arveni both produces and utilises 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, to be showcased at  Munich.

The 12-key radio remote is an intermediate step towards a fully functional remote control eg. for TV applications. The device, completely batteryless, uses a powerful piezoelectric microgenerator, which delivers up to 90mW.

Basic Hardware Platforms
Other companies are approaching the market for energy harvesters very differently. Johnson Matthey, for example, provide their customers with three basic designs for energy harvesters and work in collaboration with them to develop the rest of the solution, completely customisable 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  (right) also offer energy management solutions (Infinergy and EnerChip ranges respectively), where 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 in Munich.