The heat harvest

摘要

Very small sensors that require only a few milliamps to power them and to send their data forward on radio links are changing the data acquisition process in many applications. The low power demands of these systems mean that several energy harvesting - or scavenging -techniques have moved from being scientific curiosities to be mainstream technologies in recent years. Wiring and installation costs typically account for up to 50% of the total cost of an industrial instrument, but the development of new manufacturing techniques in terms of "printing" sensors or low-cost DAQ units means that measurement is routinely done in new areas a long way from the traditional markets for control and instrumentation.