This means you’ll never have to plug in your phone again
A breakthrough wireless power set-up that uses infrared light might spell the end of the last cord left in our lives
Nikola Tesla, the eccentric Serbian-American engineer born 150 years ago, wanted to give the world free electricity. Tesla, financed by the banking tycoon JP Morgan, designed a system for sending electricity over the air through a series of enormous towers that would create a “global wireless power grid”.
Newspapers at the time said the project would “run all the Earth’s industries”. The project, however, turned out to be more expensive than first thought. Morgan lost interest and Tesla, wracked by failure, suffered a nervous breakdown. The US government blew up his 57m test tower in 1917 amid fears it was being used by spies. Instead, the electrical revolution was wired.
But a century after Tesla’s dream died, the idea of wireless power is again gathering steam.
Electricity transferred over the air could mean cellphones that never have to be plugged in, lights that don’t need a connection, and devices from security cameras to thermostats that do not need batteries.
“The power cord is the last cord left in our lives right now,” says Sanjay Gupta, president of the AirFuel alliance, a consortium investing in wireless power systems.
Supporters say the technology could make cables and power sockets anachronisms like the dial-up modem. Today, the wireless charging systems available to the public involve placing a smartphone on a pad. Such “inductive charging” technology involves magnetic coils creating an electrical field, picked up by a sensor in a phone. However, the experience offers little more than plugging in a cable, since the charging works at a maximum distance of an inch.
That may just be about to change.
Wi-Charge, an Israeli company founded in 2012, has developed a charging system that uses infrared light to beam energy from a ceiling transmitter to a device anywhere in a room. Yuval Boger, its chief marketing officer, says the system can fully charge a phone in three to four hours, compared with about an hour when plugged in.
“Today we have become enslaved to our phones, we worry about how much battery we have. If it can be perpetually charged [it’s different],” he says.
While not on sale today, Boger says that almost every major electronics company has been in touch with Wi-Charge.
Gupta, of the AirFuel Alliance, is pushing a rival technology using radio waves. It transmits power at frequencies traditionally used by mobile networks, radio and TV. The alliance includes Samsung, LG and Huawei, and a handful of products already use the technology, including a hearing aid that can be charged at 4.5m.
The competing technologies both have downsides, however. Infrared charging requires a direct line of sight between a transmitter and a device, meaning couches, walls and pockets would block the signal. Radio frequencies of the type proposed by AirFuel have their own challenges, particularly with regards to how much power can be sent over the air safely.
Professor Grant Covic of the University of Auckland’s electrical, computer and software engineering department says health concerns around radiation and interference with devices such as pacemakers will restrict the amount of energy that can be transferred. “The limitation will always be safety. Cellphones are always getting power hungrier and the battery demands are going up. Would the energy you could transfer be sufficient?” he says.
AirFuel admits that smaller and less power-hungry devices such as headphones and wearable devices, rather than smartphones, are likely to be the main beneficiaries of its charging technology.
Disagreements over competing standards threaten to hold back the technology, says Dan Bladen of Chargifi, a British start-up. “It’s technically possible but it’s not going to happen any time soon because of the standards. Pretty much all of the companies are working on their own technologies,” he says. That means the day when users can latch on to a wireless power signal in a coffee shop or airport to charge their phone, in the same way they can with wifi today, is unlikely any time soon.
But the one company with the influence to force the technology forward might be doing just that. In 2018, Apple signed a $600m deal with Britain’s Dialog Semiconductor to acquire much of its power management technology. Dialog, in turn, has been a major investor in wireless power company Energous. Apple is notoriously secretive, but patents hint that it is working on over-the-air charging. The final wire left in the house might not have long left.
– © The Sunday Telegraph