Shocker: The world is going wireless. We eliminated the wires that transmit sound. Pictures. Text. Data. Now, there’s only one major cable left to ditch: the power cord.
That’s the dream, right? Your phone charging all day, in your pocket. Your smartwatch always juiced up without leaving your wrist. Thinner, lighter, more shapely gadgets, freed from the obligation to contain a huge blocky battery.
Plenty of companies are working on through-the-air charging for consumer electronics. But none have products on the market, and plenty of people (and investors) are skeptical that the concept will ever work. Too many safety, efficiency, and regulatory obstacles, they say. (Here, for example, is my investigation of the Energous distance-charging technology.)
Another startup, called Ossia, thinks that it may have licked all three problems.
How Ossia’s system works
Like its rivals, its system (called Cota) involves a transmitter, which will someday be built into walls or ceilings, and a tiny receiver, which will someday be built into our phones and other devices.
(Cleverly enough, Ossia has also packed its receivers into AA batteries, so that our smoke detectors, thermostats, remote controls, toys, and game controllers can charge wirelessly, too.)
Energous, as I reported earlier, works by beam forming: Its transmitter contains hundreds of tiny antennas that focus on your phone. But Ossia founder Hatem Zeine says that beam forming isn’t nearly targeted enough. “The signal is as wide as the emitter,” he says. “It never gets any smaller. Your device will get some power, but so will all the environment around it. Your whole body would be receiving power.”
His solution also involves thousands of tiny antennas. But his breakthrough is a clever call-and-response system that tells the transmitter where to send its power. Your phone pumps out a beacon signal: “a very short pulse—microseconds. It says, ‘I’m device A7374; I would like some power.’” This beacon signal reflects off of walls, windows, and people. (The power of this signal, Zeine says, is 1,000 times weaker than Bluetooth.)
Each antenna in the transmitter receives that beacon signal from all of those paths, including the direct line-of-sight signal, if available. Now the transmitter knows where your gadget sits—and it sends power right back through those same paths.
In other words, Zeine says, “non-line-of-sight charging is therefore possible. If line of sight is available, we’ll use it. But if not, we’ll use the other paths. We’re going to just play back the incoming beacon path.”
Since the phone pumps out 100 beacon signals per second, it’s OK if it’s moving around the room in your pocket. The power beam stays locked on it.
So how much power are we talking about? “The power is proportional to the area of the transmitter,” Zeine says. “We can charge a phone with 1 watt at three to six feet with a single [transmitter] tile. But we can also install multiple tiles—for example, in a ceiling—to cover a conference room or an airport gate. That way, we could charge eight phones at the same time in an area of 15 to 30 feet.”
To prove that Cota works, Zeine brought one tile, two feet square, to the Yahoo office. He also had a palm-size receiver containing a USB jack. I plugged an unprepared Android phone into it—borrowed from Alan, our sound man—and sure enough, it began charging. The receiver box was about five feet from the transmitter.
We also tried a Samsung smartwatch. We plugged its charging stand into the Ossia wireless receiver—and sure enough, the watch unmistakably began to charge.
But how could I test Zeine’s claim that Cota doesn’t need line of sight—that it’s constantly reconfiguring its beam path? After all, you can’t see the power beam, right?
To solve that problem, Zeine produced a tiny detector paddle. It lights up only when it’s in the beam’s path.
By moving the paddle up, down, left, and right, and watching when the LED illuminates, I could very clearly see the path from the transmitter to the receiver. It was like using a candle flame to detect the stream of moving air from a fan.
The paddle lit up whenever it intercepted the imaginary line between the transmitter and receiver—obviously.
But when I stepped in between them and held the paddle in front of me, the light went out—yet the receiver was still receiving power! (How did I know? First, because the receiver has its own indicator light. Second, if we put the paddle next to the receiver, it lit up again.) Clearly, the power signal had found a new path around me—probably by bouncing off the walls and the ceiling. You can see all of this in the video above.
If you’re clever, you’re already seeing the downside of this arrangement: It works only indoors. If you’re outside, there’s nothing to reflect the signals, and so the “no line of sight” feature goes away. Sorry about that, campers.
Ossia doesn’t intend to manufacture anything. Instead, it will license its technology to electronics makers.
Before it can do that, of course, it must receive the FCC’s approval, which is a looming obstacle for any wireless-tech company.
“We’ve shown that we can meet all the FCC’s requirements. Of course, there’s a lot of work we have to do. We don’t have a product—this is not going to market yet. But once these steps are completed, we will see products on the market. We believe that this is within 12 months from today.”
Zeine admits that the doubts and troubles faced by his competitors have made the whole industry look bad. (An ex-engineering executive from rival uBeam, for example, said that uBeam’s technology is basically a hoax.) All of that makes his job harder.
“People are very skeptical. But it’s also good, because it has created a lot of publicity for the wireless power market,” he says. “What others do, good luck to them. But we are the only company that’s demonstrated its product in public. We’ve also tested for safety. So we know that our technology can deploy. It’s not is a matter of if. It’s a matter of when—when we complete all the regulatory requirements, and so on.”
In any case, he’s convinced that through-the-air charging will, one way or another, become a thing. “In a few years’ time, it will be like Wi-Fi. You’ll have it at the office, at home, in the car, on the plane, the coffee shop, et cetera. You won’t need to carry a 600-hour standby battery and a 12-hour talk-time battery. You’ll need maybe a one-hour talk time battery and a 50, 60-hour standby battery, because you’re getting power all the time.”
Your phone will be thinner and more powerful, because its processor and screen can be brighter and faster.
Why is he so confident? Because analysts estimate that by 2020, we’ll have a trillion Internet of Things gadgets—smart devices—in our homes. “And anything with the word ‘trillion’ in front of it is going to be lucrative,” Zeine points out.
In case you were wondering, Ossia isn’t some nonsensical made-up word. In Latin, it means alternative. If you’re a musician, maybe you’ve seen sheet music examples like this one, where “ossia” offers an alternative, usually less difficult line to play or sing:
It’s a great name for Hatem Zeine’s technology—both because the whole thing presents an alternative way to charge things, and because the power is constantly finding alternative paths to your phone.
Now let’s just hope it finds a path to our phones and gadgets.
More from David Pogue:
David Pogue, tech columnist for Yahoo Finance, welcomes nontoxic comments in the comments section below. On the web, he’s davidpogue.com. On Twitter, he’s @pogue. On email, he’s firstname.lastname@example.org. You can read all his articles here, or you can sign up to get his columns by email.