The IoT, or Internet of Things, has increased the availability of data. Sensors are deployed to measure, for instance, temperature, infrared waves, motion, acceleration, levels, humidity or event proximity of other things. Sensors can be used in pretty rough places, faraway places. They need energy to operate, but not all sensors are in places with available power.
Or are they?
“Batteries often provide the answer, of course, but replacing them raises logistical problems, particularly at sites such as offshore wind farms or weather monitoring stations, where the task would be difficult, costly and potentially risky,” said Financial Times recently.
Another scientist described it like this: “In many IoT applications, devices need to be powered in a self-sufficient and sustainable fashion. A solution is to scavenge and harvest energy from the environment and then provide enough energy to the devices to perform their operations.” (Source)
Energy harvesting, finding small amounts of power in unlikely places is an answer. FT cited examples: “Using photovoltaic materials to generate power from light, piezoelectric energy from vibration and thermoelectric power from heat.”
An offshore wind turbine is an example it notes. Vibration from the tower can power its own sensors that monitor wear on the tower itself, anticipating when crews will need to repair or replace the structure.
Limited data limits the IoT. Finding these minute sources of power keep good data coming in so society makes the most of increasingly sophisticated data analysis capabilities.
Maybe the most unusual power source ECC saw: “Researchers from the University of Hong Kong have developed a device that can provide energy by walking. …A wearer’s knee is linked to an energy harvester which could generate 1. 6 microwatts of power while the wearer was walking. Small electronics like GPS devices and health monitoring equipment can be provided with enough power through this amount.” (Source)