Wireless charger powers devices within a 30 feet envelope

Nikola Tesla’s dream of wireless energy transfer may soon be upon us, at least according to one company’s demonstration at this year’s Consumer Electronics Show in Las Vegas. That company, called Energous, has set up an entire hotel suite dedicated to demonstrating how their technology can harness electromagnetic waves to create a new type of wireless charging system capable of powering devices up to 15 feet away. And it’s safe too (they claim).

The reputed device is called the WattUp system, and its cigar boxed-sized power transmitter transfers energy by way of converting focused radio frequency (RF) signals into DC power. According to Energous’ online demo materials, WattUp is able to power up to 12 devices simultaneously, ranging from smartphones, tablets, and wearables, to wireless keyboards, headsets, LED bulbs; essentially, any battery-powered device. The caveat: the objects must be fitted with proprietary receivers.

Energous explains that the system functions by scanning the location for all nearby devices before transmitting multiple low-power beams — bouncing them off walls, ceiling, and floor (much like a Wi-Fi signal) — to create an “energy pocket.” On the receiving end, multiple micro antennae snag the signal and embedded chips covert it into DC power.

We are assured that the system is safe as the technology transmits power over the same radio frequency spectrum as Wi-Fi routers and cordless phones. Similarly, energy density remains consistently low at any one because RF waves are only sent out when requested by the receiving device; if no device has sent a power request, or if there are no receivers present in the room, the transmitter goes on stand-by. But in the event that a charge is requested, the WattUp receiver will communicate with the transmitter via Bluetooth, activating the transmission. 

WattUp’s power transmission is remotely managed from a web interface that allows users to specify which devices to charge and in what priority. It is from here that users can allocate power to devices in increments of ¼ W ranging up to 4W. Maximum power is dependent on range. For instance, 4W can delivered simultaneously to 4 devices within 0-5 feet, 2W within 5-10 feet, and 1W within 10-15 feet.
Since a finite amount of energy is allocated between the total number of devices, charging time is commensurate with that number. Energous states that four devices charging at full power will charge at the same rate as if they were plugged into a wall socket, whereas four devices within a 5-10 feet range charge at the same rate as being plugged into a USB port.

Energous is hoping to license the technology to other companies and create a new standard in battery charging; it’s reputedly already in talks with Foxconn. 

Source: Energous