Freevolt: RF energy harvesting to power the Internet of Things(arstechnica.co.uk)
arstechnica.co.uk
Freevolt: RF energy harvesting to power the Internet of Things
http://arstechnica.co.uk/gadgets/2015/09/freevolt-perpetual-free-rf-energy-harvesting-to-power-the-internet-of-things/
3 comments
To save you time: All of which are empty.
This made no sense back then. It still makes no sense now. You can't harvest useful amounts of RF energy.
This made no sense back then. It still makes no sense now. You can't harvest useful amounts of RF energy.
Well for a suitably frugal definition of "useful", you can. See their whitepaper: http://getfreevolt.com/downloads/RF%20Energy%20Harvesting%20...
Any EE experts around, willing to validate their assessments?
We asked Lord Drayson if there were any limits on the number of Freevolt harvesters in a given area, or if there was a critical number of harvesters that would then impact cellular or Wi-Fi signal reception. He said "no" in both cases.
Both these answers are simply wrong - they are absorbing power from the RF spectrum. Of course there will be some impact.
Both these answers are simply wrong - they are absorbing power from the RF spectrum. Of course there will be some impact.
Well~
In fact "no" is probably the right answer, unless you use enough of them to build a Faraday cage. That's because they pick up practically no power at all, though.
In fact "no" is probably the right answer, unless you use enough of them to build a Faraday cage. That's because they pick up practically no power at all, though.
This technique was already used in the 1930s by people living close to the powerful AM transmitters in Berlin and Hamburg to run electric lights. It was outlawed, though.
https://news.ycombinator.com/item?id=10308511
https://news.ycombinator.com/item?id=10306293
https://news.ycombinator.com/item?id=10304387