Is through-the-air charging a hoax?

David Pogue
Tech Critic

In June 2015, in my Yahoo office, I watched a demonstration of the most amazing new technology I’d seen in years: distance wireless charging. It looked like Nikola Tesla’s 100-year-old dream coming true.

Steve Rizzone, CEO of a company called Energous (WATT), turned on what looked like a WiFi router—and several feet away, a phone in my hand started charging. The transmitter contains an array of small antennas. They focus their radio waves on your phone.

CEO Steve Rizzone (right) shows me through-the-air charging in 2015.

Here’s the video. And here’s what I wrote:

Your phone, tablet, smartwatch, hearing aid, and fitness band will be charging all the time, as you go about your day. You won’t take them off. You won’t plug them in. And you’ll never worry about making it through the day on a charge.

A product’s battery life, in fact, will become irrelevant.

Rizzone said that all of this is completely safe. The transmitter is sending out RF (radio frequency) signals—the same kind transmitted by WiFi or cellphones.

The aftermath

We posted the story and the video. We were excited; the readers were excited.

Well, all but one.

I began to get email from an independent investor who identified himself as Todor Mitev. (We couldn’t verify his identity.) He was suspicious of the demonstration.

David: I have some questions about the Energous demo…I saw some unexplained turning on and off of the green “charging” circle of the phone display, but Steve wasn’t doing anything, so somebody else must have been controlling the transmitter…

I responded that he was no doubt seeing a continuity error in the video editing.

But that didn’t satisfy Mitev. Over the months, he kept writing, finding flaws in Energous’s public statements, critiquing its science, flagging misspellings in its filings, and insisting that I needed to dig deeper.

Mitev also sent me articles from an investing website that cast doubt on whether Energous could get FCC approval for its technology. Without that approval, it can never go on sale in the U.S. And he suggested that I’d been manipulated:

It has been about a year since the fake Energous demo. Energous is using your quote on its website (“I don’t say this often, but I think we are looking at the future of technology.” — David Pogue, Yahoo Tech). Effectively, you are facilitating the fraud perpetrated by Energous.

Facilitating fraud!? Them’s fightin’ words. No journalist wants to be anybody’s pawn.

The return visit

If Energous is a hoax, I’d rather expose it than play along with it. So I decided to visit Energous’s headquarters in San Jose, California, to get to the bottom of this.

2017: Return to Energous.

Many of Mitev’s concerns seemed nitpicky, but a few were solid. For example:

  • In 2015, Rizzone told me he planned to ship Energous’s technology by the end of 2016. Now here we are, well into 2017, and still … nothing. What’s going on?
  • Energous’s transmitter tracks your phone’s position in the room using Bluetooth. But if your phone is completely dead, there’s no Bluetooth. Then what?
  • This one’s geeky, but important. The FCC permits wireless charging in two categories. The first (“Part 15”) is for things like WiFi: long distances, but very weak power. The other (“Part 18”) permits more power—but only if it’s localized or contained, as in a microwave oven. Neither rule permits a product to transmit enough power to charge a phone from several feet away.

And so, for the second time, I sat down with Steve Rizzone, the CEO.

More questions for CEO Steve Rizzone.

First question: Why isn’t Energous shipping anything yet?

Two reasons, Rizzone said. First, Energous has partnered with a big U.K. semiconductor company called Dialog. “They are the world leader in Bluetooth and power-management chips,” Rizzone said. “Their customers are our customers.”

Dialog will handle the operational aspects of Energous’s business: testing, supervising manufacturing, shipping, inventory, and sales. “We transferred all of our back-end operations over to Dialog. And it took time to do that,” Rizzone says.

The second reason for the delay: Energous is now working on three products. There’s “near-field,” or contact charging (like those Samsung Galaxy charging pads), midrange transmitters (three-foot range), and the original 15-foot transmitter.

“We changed our vision,” Rizzone says. “When we talked about two years ago, the near-field was not part of the vision. This is a very opportunistic, significant revenue opportunity for us. So it made sense, as a company, for us to do a slight left turn, and to move forward with this technology.”

Despite these course corrections, “we think that Dialog will be shipping chipsets to our early adopters next quarter, and those will be incorporated into consumer-facing products that we should see the end of Q3, the beginning of Q4 of this year,” Rizzone says. (Energous sells its tech to other electronics makers, which can embed it into their products.)

In other words, Energous now says it will ship this fall—2017.

The FCC question

What about that Part 15/Part 18 business? How will Energous get FCC approval if its technology doesn’t fit either category?

“We’ve been working for quite some time now with the UL [what used to be Underwriters Laboratories, an independent certification company] and other agencies,” Rizzone says, “to perfect a process that will allow for testing of these devices that will meet the requirements as mandated by the FCC. And we’re very close to that.”

Energous is trying to persuade the FCC that its products already fit within Part 18. Here’s the argument: Energous’s multiple antennas focus on a tiny spot in your phone. So the power is, in effect, localized, just as though it were on a charging pad.

Even so, Energous has been working with the FCC for a year to develop a testing protocol for this new world of wireless power.

“Prior to this to test, as an example, there’s [been] no way [to measure] SAR, or the amount of energy that’s being absorbed by the skin, at a distance. And so not only did we have to work with the agency, we had to work with laboratories to actually develop a mechanism to test this,” Rizzone goes on.

“It’s taken us, what, 16, 18 months to reach this point. But we have a very thorough understanding of what the expectations are for results, and the methodology to test, and we’re well down the line with actually completing these tests.”

Rizzone points out, too, that these new tests don’t just serve Energous; its rivals will be able to seek approval, too.

The charging pad

Gordon Bell, Energous’s VP of marketing, demonstrated all three of the Energous products for me: the near-, middle-, and far-field transmitters.

First, charging pads. Energous had set up sample charging pads and charging bowls; when I put specially equipped Fitbits and Bluetooth headsets on them, they began charging on contact (in fact, slightly before contact). We put two and even three of them on a single pad; they all charged at once.

This technology, Bell said, is ideal for charging phones, Bluetooth earbuds, GoPros, and so on.

The Energous near-field transmitter prototype, shown charging three things at once.

So how is this any different from those Qi chargers, the ones the Samsung Galaxy can use?

“Number one, the ability to charge at a 90 degree angle,” Bell said. “And being able to move around and not have to put it in one specific location. If it jostles in the car or something, you don’t lose charging.”

Bell also said the cost for the Energous technology (both transmitter and receiver) is much lower than Qi—and the size is better, too. “Our antennas and ASICs [circuit boards] can go inside a very small, in-the-ear hearing aid. You’ve not seen that type of charging in the older wireless charging, because they just can’t get that small,” Bell said. “Imagine just taking your hearing aids out at night, putting them next to your clock radio, and you wake up the next morning, they’re fully charged. You never have to fumble around with batteries again.”

Energous’s pad also runs cooler, he says. “This is key for solutions that reside on keychains like Bluetooth trackers and car remote key fobs.”

Finally, the big one: Any gadget that can charge on the pad will also charge from the mid- and far-field transmitters, once they’re available. It’s all the same technology.

The FCC has already approved Energous’s contact-charging technology. Bell says that at least six companies have announced that they’ll incorporate it into their products, and other companies are committed but haven’t announced it yet. “You’ll see our customers including this near-field technology inside the box. We anticipate that coming before the end of this year,” Bell says.

The desktop transmitter

Next, he showed me what looks like a mini TV soundbar—mounted under an iMac’s screen. “It gives you the function of charging devices [with a] two- to three-foot range. It could be in the bezel of a small television, the bezel of your computer monitor, the bezel of your laptop screen. It could also be on something that’s already on your desktop. Maybe it’s a Bluetooth speaker. It could be the front seat of your car,” he said.

This keyboard has been rigged to light up while charging from the charging bar, which peeks out just under the Apple logo.

He showed me a wireless keyboard and mouse. Both lit up to show that they were charging when they were within a couple of feet.

Or at least they did when an assistant turned on the transmitting power.

Energous transmitters, it turns out, are not constantly sending power. “The transmitter speaks to different devices via Bluetooth, and identifies, number one, what’s the battery level?” Bell explained. “A transmitter might say: ‘This desktop keyboard, I’m going to charge that on September 14th. And this mouse, I’m going to charge on December 8th.’ But for demo purposes, we have to manually do it.”

Bell stressed that it’s a “very, very small amount of power. We’re not charging a car, for instance. It charges over time.” But he doesn’t think consumers will care.

“It’s the same sort of thing as what we had with Ethernet versus Wi-Fi. If I told you 15 years ago that I had something really cool—compared to Ethernet, it’s super slow, and it’s going to cost a lot of money to install, and it’s not as secure as Ethernet. But Wi-Fi has the flexibility to let you roam around the room. And that’s what this does.”

The far-field transmitter

Finally, I saw again the Holy Grail: the whole-room charger, with a 15-foot range, capable of charging up to 12 gadgets simultaneously. It was a box mounted above a wall TV.

The far-field transmitter (inset, lower right) is also the farthest from being ready.

“What will come to market, actually, won’t even look like that. It might be in the speaker bar underneath your TV. Or it could be on the front of a dorm-room refrigerator.”

And yes, he said, this would allow your phone to receive a charge in your pocket as you move around. “As long as you’re in that 15-foot range, you’ll be charging. Small, small amount of energy. It’s not charging super fast, like you would be plugged in the wall, but a small amount of energy, trickle charging it. And as you put it down closer or farther away, the amount of power changes.”

I asked if the charge would be stronger when you’re not handling the gadget. “Yeah, we might be able to turn the power up a little bit higher,” Bell said.

Here again, Energous says that it won’t be all charging, all the time. “For instance, the remote control for your TV. The transmitter is going to identify that, ‘maybe I’m going to charge that on August 14th. And the game controller, I’m going to charge that on September 8th. And the phone I’m going to charge every day, because they drain so fast. But my Bluetooth tracker over there, maybe I charge that on June 4th. And my fitness band I’m charging on a weekly basis.’ So it really depends on the device and the drain of the battery for the device.”

I remembered Mitev’s questions. “What if my phone is totally dead and therefore it doesn’t have Bluetooth working?”

“You might be able to set up a charging spot,” he said. “You’d have a button that’s on the transmitter; click the button, and it will send power to a specific, designed area. Maybe that’s the corner of your coffee table. And then, a couple minutes later, you have enough power to do the tracking.”

Those “it might work like that” responses suggest the far-field transmitter still needs some work. No wonder Energous says that it will be the last to get approved. “We anticipate products from partners in the second half of next year,” Bell says, “and we expect FCC approval ahead of that time.”

A scaled-back claim

I’m glad that Mitev’s suspicions prompted me to make another visit. Because there definitely were some aspects of Energous’s presentation that I’d missed the first time around.

For example:

  • Energous’s timeline was far too optimistic.
  • They’re cagey about revealing power ranges and efficiency.
  • The business about scheduling gadgets to be charged on certain dates seems weird and unnecessary.
  • No existing FCC testing protocol will accommodate distance-charging products.

Above all, Energous has backed down from its 2015 vision of phones charging up in our pockets.

“Several watts at a distance? No,” Gordon Bell told me. “As we’ve learned a lot more, we’ve tempered that [claim] down. We talk about 5 watts at a very close distance, but not at distance anymore. It’s more of a trickle charge for a phone. Now, if you’re constantly on the phone, 15 feet from the transmitter, that’d be hard for us to increase the battery. We’d just keep it from going down.”

And sure enough: During my return visit, Energous never demonstrated its transmitters charging a phone — only low-power gadgets.

The Mitev question

But what about Mitev? What is his deal? Why is he so aggressive in calling Energous a fraud?

When I asked him, he solved that mystery rather neatly: He’s a short-seller.

Andy Serwer, editor-in-chief of Yahoo Finance (and my boss), explains short-selling like this:

“Short-selling is betting that a stock goes down. Usually when you invest, you put money in, and you hope the stock goes up.”

It’s legal and useful, but it’s also risky. “If it doesn’t go down, you lose money. It’s a big bet, and you can lose all your money, very quickly. So it’s a dangerous game,” Serwer said.

Mitev, in other words, has “shorted” Energous stock—and now has a financial interest in making the Energous stock go down. He even admitted that he wrote some of those critical articles online—using a fake name!

(“I typically don’t use my real name because, in the past, I have received direct threats to my life when I have researched or written about frauds,” Mitev says.)

That kind of article wouldn’t have any effect on, say, Apple stock or General Motors stock. But as a public company that doesn’t yet have a shipping product, Energous is a sitting duck.

“Energous is a small company,” Serwer says. “So it’s very sensitive and small and volatile, and very susceptible to manipulations of this sort. Small investors might panic more easily. They don’t know this guy—they see him putting these articles out, and it’s scary.”

Short-sellers like Mitev try to frighten other investors out of the stock. “The stock’ll go down, you make your money, and you clear out,” Serwer says.

The whole business strikes a nerve in CEO Rizzone. “You know, short-sellers, they play a role on Wall Street. They serve a value,” he says. “But what I think is unfair about the whole thing is that we’re obligated to tell the truth. We have to. We can go to jail. We have to sign things every quarter. However, short-sellers are free to say whatever they want. And you have some very, very intelligent short-sellers, like Todor, who have just enough information to cobble together stories that sound convincing. But they have no idea what’s going on within the company.”

Distance charging in the distance?

Energous isn’t the only company working on distance charging. And it’s not the only company that’s been accused of making impossible promises. All of the competitors have impressive demos, and each insists that it has the best technology. Here are some of the key players:

  • PowerCast. Charles Greene, chief operating officer, told me that this technology is already the on market—for charging industrial sensors and RFID tags. Consumer products are his next goal. What PowerCast is proposing, however, isn’t much more convenient than charging pads: You have to leave your gadget in a particular spot overnight. In other words, PowerCast’s technology can’t keep our phones and smartwatches charged as we wear them. “We’re focused on applications that are off-body,” Greene says.
  • WiTricity. “You will not hear me talk about showering a room with energy,” says CEO Alex Gruzen. “We’re talking about near-field”—that is, charging pads. But unlike Samsung-style Qi charging pads, WiTricity’s magnetic-resonance technology can transfer huge amounts of power—with the same charging speed and efficiency as the power cable—and permit very sloppy positioning. The company is working with “almost every automaker in the world” to make charging mats for electric cars, Gruzen says. “Just park your car, and it starts charging.” WiTricity’s tech is also in the new hybrid Dell Latitude 2785 laptop, which charges at full speed when you set it down on its mat.
  • uBeam. This company’s technology uses ultrasound waves, rather than radio signals, to send power to consumer devices. Unfortunately, uBeam requires line of sight—the receiving device can’t be blocked by anything, like your body, or even your pocket. The phone can’t move around, or even change angle. (This is the technology called fraudulent in 2016 by a former engineering executive.)
  • Ossia. This company, like Energous, employs an array of hundreds or thousands of antennas. With a big enough array (four “tiles”), the company says it can send your phone 1 or 2 watts from 20 feet away. The clever part is how the transmitter tracks your phone in space: The phone sends out 100 “beacon” pulses a second; the transmitter returns RF power waves along the same paths. Because the outgoing signals follow the same pathway as the beacon—even if they’ve had to bounce off walls, floor, and ceilings—there’s no line-of-sight requirement. Founder/CTO Hatem Zeine told me that they, too, have been working with the FCC and expect approval “soon.” He also says that Ossia has electronics companies already signed up as customers.

Where does the truth lie?

Our friend Mitev is certainly guilty of overzealousness. According to Energous executives, Mitev tried to slip into Energous’s demo hotel suites, uninvited, at the Consumer Electronics Show in both 2016 and 2017. (Mitev says that he did nothing wrong.) And writing articles under fake names seems a little shady.

But he genuinely seems to believe that he’s onto something.

“Energous is a fraud,” he told me. “The company has raised over $100 million while repeatedly misleading investors and the public. The company knows its FCC-approved devices are not commercially viable. The company also knows that its charging-at-a-distance technology has no path to regulatory approval.”

The whole concept of distance charging seems to be fraught with doubt and uncertainty, even to the experts. I asked James Kirtley, professor of electrical engineering at MIT for his opinion. (He’s a specialist in electric power systems, 2002 Nikola Tesla prize winner, and a member of the US National Academy of Engineering.)

“I don’t like saying ‘never’ or ‘can’t work,'” he replied, “but I would be skeptical. My guess is that this sort of system, with phased-array antennae, might work, but it is probably not very efficient.

“[On the other hand,] modern radar sets use phased-array antennae, and they can indeed focus on small regions of space. I have heard of phased-array antennae generating field strength high enough to ionize regions of air (blue flames!). Of course, you would not want to do that for a cellphone charger, so much lower field strength is required. And you probably only have to deliver a watt or so to do the requisite charging. I guess the relevant question is, how much power do you have to put into it to get that one watt at the device?”

And that, of course, is information that Energous won’t divulge.

Still, if Energous really is trying to commit a hoax, it’s going to a lot of trouble. I met many of the company’s 100 employees, and saw certificates for its its 27 granted patents. I toured its anechoic testing chamber, which measures radio signal as it’s sent to a phone from different angles and distances. I interviewed Marty Cooper, the father of the original cellphone, who’s an Energous board member (and knows a thing or two about wireless technologies).

And Energous says that it’s still working with its silent partner, a huge unnamed “tier one” electronics company (“it’s highly likely that you own some of this company’s products,” Rizzone told CNN back in 2015)—that has committed to putting Energous technology into “millions of devices.”

So far, the FCC has approved only Energous’s charging-pad technology. No surprise; we’ve seen that sort of thing before. We know it’s safe and doesn’t cause interference.

The real question is, will the FCC also approve the mid- and far-field transmitters?

“The announcement of the FCC approval, which we anticipate in the not too distant future, is going to put a lot of this to rest, because the FCC is not going to approve something that’s not safe, that’s not workable, that doesn’t have scalability,” Rizzone says. “We’re on the cusp here. We think that this will all be in the rearview mirror in the next six months or so.”

Energous is no longer promising the dawn of battery-life irrelevance, as it once did. But if distance chargers from Energous or Ossia do get FCC approval, then our phones and gizmos will last a lot longer on a charge. Eventually, products can be thinner and sleeker because they’ll contain smaller batteries. Entirely new classes of electronic products could be born. The charging technology could find its way into trillions of devices.

I never did manage to find out exactly how realistic through-the-air charging is, how close it is to appearing in our phones and watches. I’m not sure anybody really knows.

But this much I can tell you for sure: As one of the Earth’s billions of gadget owners, I really want through-the-air charging to become a thing—and for Todor Mitev to be wrong

Correction: The original version of this story and video included an oversimplified explanation of short selling (“It’s like buy high, sell low”); stated incorrectly that large institutional investors haven’t bought Energous stock; and misstated the FCC rule that permits Samsung’s Qi charging pads. It’s permitted under Rule 15, not Rule 18. The story and video have both been corrected.

More from David Pogue:

Electrify your existing bike in 2 minutes with these ingenious wheels

Marty Cooper, inventor of the cellphone: The next step is implantables 

The David Pogue Review: Windows 10 Creators Update

Now I get it: Bitcoin

David Pogue’s search for the world’s best air-travel app

The little-known iPhone feature that lets blind people see with their fingers

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 poguester@yahoo.com. You can read all his articles here, or you can sign up to get his columns by email