Wi-Fi will power phones? NOPE

In which Richi rails against stupid science churnalism -- do the math, people!


Researchers have improved our ability to capture power from radio waves. By tweaking some standard Wi-Fi hardware, they've increased the amount of power that can be leeched from unused transmissions. They reckon it could power sensors for [buzzword warning] The Internet Of Things.

But wait -- don't believe everything you read on the interwebs, kids. Predictably, some science-illiterate journalists and bloggers are saying the technology can actually charge your smartphone. Sadly, the researchers only achieved power levels of a few µWatts -- that's about 100,000 times too small to run your phone, let alone charge it.

In IT Blogwatch, bloggers get out their pocket calculators.

Your humble blogwatcher curated these bloggy bits for your entertainment.

This pseudonymous arXivist finds an interesting paper:

Great things are expected of the Internet of things but only if engineers can solve one potential show-stopper:..how to power these numerous tiny machines.

Vamsi Talla and pals at the University of Washington in Seattle...have developed a way to broadcast power to remote devices using...ordinary Wi-Fi. They call [it] power over Wi-Fi or PoWi-Fi.

[They] use three Atheros AR9580 chipsets [and] program these devices to broadcast in a way that can provide continuous power to an energy harvesting sensor. [They tried to run] a low-power Omnivision VGA sensor capable of producing 174 x 144 pixel black and white images, which requires [0.003 mWh] of energy per picture. ... “The battery-free camera can...capture every 35 minutes,” say Talla and co.  MORE

And Aunty speaks unto nations, educating and entertaining in equal measure: [You're fired -Ed.]

The...camera was modified so it could scavenge power from ambient wi-fi signals, store it and then use it to take photos.

Because wi-fi signals are broadcast in bursts across different frequencies the required amount of energy was only available too intermittently to be useful. [So] the research team modified standard wi-fi hotspots and routers to broadcast noise when a channel was not being used.  MORE

But Brian Barrett gets a tiny bit over-excited:

It’s easy to take Wi-Fi for granted. [But] what if instead of just connecting your devices to the Internet, it charged them as well?

Forget power mats and battery packs; the energy we need is already all around us. Now we have a way to harness it—and stay connected, too.  MORE

And each time a story is repeated, it gets a little more wrong, as Jessica Mendoza illustrates:

Researchers at the University of Washington (UW)...“power over Wi-Fi” technology makes it possible to recharge devices wirelessly...nearly 30 feet away.

The concept of wireless power is a throwback to Nikola Tesla.  MORE

And so, we go from the sublime, to the ridiculous:

Forget about the wires, even power banks, researchers at the University of Washington are looking at a future where you will be able to use WiFi to recharge your mobile phones.  MORE

You have been reading IT Blogwatch by Richi Jennings, who curates the best bloggy bits, finest forums, and weirdest websites… so you don't have to. Catch the key commentary from around the Web every morning. Hatemail may be directed to @RiCHi or itbw@richi.uk. Opinions expressed may not represent those of Computerworld. Ask your doctor before reading. Your mileage may vary. E&OE.

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