Researchers discover battery-free technology that harvests power from radio and Wi-Fi signals for low-powered devices

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Researchers at the National University of Singapore (NUS) have found a new type of energy harvesting module which extracts energy from radio frequencies (RF).
Typically called 'waste energy', these modules convert the RF signals into DC voltage which can be used by low-powered devices. The radio frequency energy harvesting modules could reduce the dependency on batteries for certain applications. Remote areas and certain situations where swapping batteries regularly is not possible. 

This research is a collaboration with other researchers from Tohoku University in Japan and the University of Messina in Italy. In the press release we can see that the research team are clear that such technology helps to reduce our dependency on batteries. This would also reduce the environmental impact of batteries, extending device lifetimes and enabling new types of wireless sensor networks and IoT devices in situations where battery replacement is not pragmatic. 

This technology also helps to extract from low RF power levels, implying its usefulness in many low-powered applications, such as temperature sensors. One of the researchers, Professor Yang Hyunsoo of the NUS said, "We optimized the spin-rectifiers to operate at low RF power levels available in the ambient, and integrated an array of such spin-rectifiers to an energy harvesting module for powering the LED and commercial sensor at RF power less than -20 dBm. 

Dr Raghav Sharma, the first author of the paper, also concurs with this assessment and stresses the importance to resolve the issue relating to conventional rectifiers. Once overcome, it would lead to the design of next-generation ambient RF energy harvesters and sensors using the new rectifier technology. 

Roshan Ashraf Shaikh
Contributing Writer

Roshan Ashraf Shaikh has been in the Indian PC hardware community since the early 2000s and has been building PCs, contributing to many Indian tech forums, & blogs. He operated Hardware BBQ for 11 years and wrote news for eTeknix & TweakTown before joining Tom's Hardware team. Besides tech, he is interested in fighting games, movies, anime, and mechanical watches.

  • AtrociKitty
    This is not even remotely new. It's also wildly impractical; either the amount of power harvested is vanishingly small, or enough power is collected that you create an RF deadzone behind the gathering device. The former is useless compared to a battery, and the latter will have the FCC after you.
    Reply
  • scostigan
    https://en.wikipedia.org/wiki/Wardenclyffe_Tower Not new at all
    Reply
  • Giroro
    Oh, cool. I remember hearing about this every couple years, for the last few decades.

    Next up, lets hear about that revolutionary new battery tech that's totally going to replace Li-ion you guys, we promise. Then after that, I'm probably going to need to know one weird trick for hydrogen power that the gas companies hate.
    Reply
  • hotaru251
    AtrociKitty said:
    The former is useless compared to a battery
    the point of this tech (i know its not new) is for stuff that doesnt "need" a battery becasue it uses such small power amounts. think a doorbell. it isnt using much power and not having to worry about battery is a good thing (as battery are not great for environment).
    Reply
  • pixelpusher220
    To me these aren't replacements for batteries, but 24/7 chargers for them. Similar to a solar cell film or something on one side of a remote. It gathers really low amounts of light from the surrounding space but keeps the batteries topped up. This though obviously doesn't need to be 'placed' as accurately or with a particular side up. Hell it might even work while *in* the couch cushions hiding from JD Vance.
    Reply
  • endocine
    All that energy from the 5G towers is what gave me COVID
    Reply
  • t3t4
    Don't even pretend like any of this is new! Those who follow Tesla's work have been doing this since the early 1900's with his patented Radiant Energy Receiver. At one point I even considered bringing a product to market since nothing existed otherwise, but it's extremely simple technology, and it's already patented. Just read the patent and build your own, or watch a YouTube video, which ever is easier. Every variation of the thing all does the same exact thing, nothing new here.
    Reply