A new company called Energous has devised a method of wirelessly transmitting power over long distances. Its prototype system can beam 10 watts, more than enough to charge your smartphone or tablet, over a distance of 15 feet — and, rather importantly, it will track your device if you move around. The company hopes to commercialize its technology soon, with partner companies showing off the tech at CES in January 2015. It seems that the first generation of wireless charging — those awful, short-range charging plates — may finally be drawing to a close. The dream of having your smartphone and other mobile devices constantly topped up — while you sit on the sofa, while you stand in line at the coffee shop — may soon come to pass.

Usually when we write about wireless charging on ExtremeTech we’re referring to magnetic resonance, where you have two coils of wire (antennas, basically) that are both tuned to a certain frequency. When you pass electricity through one coil, it induces a resonant electromagnetic field in the other coil, (fairly) efficiently transferring energy through the air. This is the method that almost every upcoming wireless charging technology uses, including WiTricity (an MIT spin-off that has been trying to bring magnetic resonance wireless charging to market for a good 5+ years). Not Energous, though.

According to Technology Review, Energous appears to use a very different technique, consisting of “lots of small antennas.” This antenna array sends radio waves to nearby mobile devices that have announced their presence via Bluetooth. Beyond that, there are sadly few few details. In the demo video above, you can see that Energous’ Energy Router can send power to two devices. The Router can also “track” devices as they move around (though there’s no word on how big an area it can track). From these details, we can infer that some kind of beam forming is used, to transmit a tight beam of electromagnetic radiation at the target device. The max range is apparently 15 feet (4.7 meters), with fairly modest efficiency of 20% (not a huge deal, when you’re talking about mobile devices with tiny power consumption).

To receive the wireless power, Energous uses special case that you slip your smartphone into. Again, no word what’s inside the special case, but presumably it’s a bunch of antennas/coils. It is these cases that will first come to market, says Energous, with partners showing off cases and Energy Routers at CES 2015. Eventually, though, of course, Energous wants to get its technology built directly into devices — and the company says it’s having receiver and transmitter chips made at the moment. This is a good sign that, despite the cases and Energy Router being rather large at the moment, the technology can be scaled down.

While Energous might not have the industry support that WiTricity has (its “Rezence” tech is backed by Intel and Qualcomm among others), it’s exciting to see another technique for wireless power transfer that doesn’t use magnetic resonance. With magnetic resonance there are some fairly strict rules (as governed by the laws of classical physics) that limit its potential for wireless power transfer. An array of beamforming antennas makes a lot of sense, for wirelessly charging multiple devices as they move through a 3D space. (If that’s how Energous actually works, anyway; I could have it completely wrong.)

Who knows. With Energous (or WiTricity/Rezence if it actually comes to market in mobile devices) we may soon be living in a world where your mobile devices can be constantly topped up, whether you’re sitting on the couch, at your office desk, or standing in line at the coffee shop. Wireless power transmission could also be the key to powering large sensor networks (smart homes, smart cities), without having to attach each device to the grid or provide them with a bulky battery.