I am obsessed with ridding devices of wires. That’s why I’ve been excited to report on the growth of wireless connectivity for the last two decades and why I’m now eagerly awaiting improvements in wireless power and energy-harvesting chips. Over the years, various wireless connectivity issues have been solved with dozens of standards, plus some proprietary options — all designed with different features optimized for certain jobs and environments.
But when it comes to getting rid of batteries, we’re still waiting on a significant breakthrough. Yes, we have the Qi standard, which allows us to set a phone or various other compatible devices on a charging mat, but that doesn’t solve the power problems in the IoT. Connected sensors and devices need over-the-air or self-contained power that can work for years without a person needing to touch the device, much less build out additional infrastructure.
That over-the-air power may be coming. Two startups are working on delivering sufficient power over the air to charge devices such as sensors and maybe even phones. The first startup, Ossia, is based in Bellevue, Wash. and has been working on its technology since 2008. Founder and CEO Hatem Zeine says he had been working on boosting Wi-Fi data rates in the late nineties when he discovered that his method of aligning antennas also sends considerable power to devices.
Ossia’s technology, which it has dubbed Cota, can transmit a few watts of power at a short distance using a transmitter and a receiver placed on a device. The technology doesn’t require line of sight between the receiver and transmitter, which means that neither furniture nor people will get in the way of charging the device. The technology works by having the receiver listen for a wave of RF from an antenna on a transmitter, then determine the inverse of that wave to send back to the antenna. That allows the antenna to align and deliver power to the right place.
If something interrupts that signal, no power is sent, which avoids some of the nightmare scenarios of a wave of power trying to pass through a body. And while it sounds far-fetched, customers such as SAP, Walmart, and others are already using Ossia’s tech in pilot projects. For example, a single transmitter embedded in the ceiling of a grocery store can power roughly 1,000 electronic shelf labels.
Obviously the ability to deliver a few watts over a distance of six to 10 feet is impressive (the wattage falls off at longer distances), and Zeine says industries ranging from automotive to construction are trying it out. He says one automotive customer wants to embed the Ossia transmitter into the dashboard of a car to power the sensors that are tracking whether or not a seat belt is fastened or an airbag has deployed. There are more than 50 such sensors in the cabin of a modern car, and providing wires for all of those sensors would add tremendously to the vehicle’s overall weight. So eliminating them could cut weight and increase fuel efficiency.
The other startup trying to deliver wireless power is in Israel. Wi-Charge has spent 10 years building its technology and has raised $30 million in funding from investors such as Lightspeed Venture Partners. The Wi-Charge technology also requires a transmitter and receiver on the device, and — unlike Ossia’s Cota — needs line of sight between the two in order to work.
Wi-Charge will charge roughly $100 for the transmitter and $10 for the receiver. The system of transmitter and receiver is about 10% efficient, which may limit the usefulness of the solution for high-powered, always-on devices. But there are plenty of opportunities for devices that stay relatively static to sip from wireless power. There’s also an opportunity to include a transmitter in lighting fixtures so that even devices that move around will generally find themselves within a transmitter’s line of sight.
So far, the company plans to install wireless charging on the Arlo video cameras, according to Yuval Boger, chief marketing officer at Wi-Charge. Schlage and other smart home device customers are interested in the technology as well. The Wi-Charge device can send 2 watts of power and is “enough to charge a cellphone,” says Boger. He expects to sell receivers and transmitters later this year.
Wi-Charge will focus first on the smart home market; Boger also thinks there will be a market for the technology in commercial bathrooms as a way to power touchless faucets and hand soap dispensers. As someone who did have a battery-powered sink at one point in time, I can see the value of avoiding battery changes, especially in high-traffic areas.
I think the need for line of sight will mean Wi-Charge’s technology will work best in environments where objects that require power are static and where transmitters can be installed relatively cheaply. For example, if you could add a transmitter to a light bulb then you could install it into the ceiling in a few spots in your home and you’d be set for devices that have the Wi-Charge receiver.
Ossia and Wi-Charge aren’t the only companies out there providing wireless power for the IoT. Others include Guru and Energous. Maybe I should give up on energy-harvesting tech and look to the airwaves for power.