We are surrounded by “electrosmog” – invisible clouds of electromagnetic radiation that enable mobile and Wi-Fi networks. If captured, it can power small devices. Now, a former British science minister Paul Drayson, a peer in the UK’s House of Lords, has developed an efficient energy-harvesting system, called Freevolt, which uses an antenna to draw power from multiple wavebands of the electromagnetic spectrum while fitting into a unit the size of a credit card. “We can’t power a mobile phone, but we’ve found that the ambient energy density is sufficient to power sensors, beacons and some wearab les,” Drayson says.
The technology, launched on Wednesday, was placed inside a personal air pollution sensor called CleanSpace, to allow individuals to monitor the air quality around them. The sensor, called Tag, pairs with a mobile app to keep track both of carbon monoxide levels and transport choices made by an individual.
Users earn points each time they walk, run or cycle. These can be traded for rewards from partners including Amazon, Boohoo.com and MaxiNutrition. The data from individual sensors is then aggregated to build up a map of the air quality.
“This is the first commercial device that is powered solely from ambient radio frequency energy,” says Drayson, who stumbled upon the idea when he came across the work of Imperial College, London, PhD student Manuel Pinuela Rangel, who was researching inductive power transfer, and set up Drayson Wireless.
The team decided to create a personal air quality sensor in recognition of the increasing public awareness of air pollution as a health problem. About 29,000 people die each year in the UK because of poor air quality each year.
Drayson now plans to license the technology to other commercial partners looking to create sensor networks, beacon-driven retail marketing tools or low-powered wearables. As it stands, the inventor contends that Freevolt could generate enough power for devices like the Fitbit Charge or Jawbone UP3. Drayson also points out that because Freevolt works across multiple bands of radio frequency , even if there isn’t any 3G or 4G signal, it can gather energy from Wi-Fi or even broadcast signals.