“…the slight convenience of juicing up your phone by plopping it onto a pad rather than plugging it in comes with a surprisingly robust environmental cost.
According to new calculations from OneZero and iFixit, wireless charging is drastically less efficient than charging with a cord, so much so that the widespread adoption of this technology could necessitate the construction of dozens of new power plants around the world.”
Nokia claimed to have the world’s first wireless phone charging in 2012 with the Nokia Lumia 920.
At the time Nokia said its wireless charging was 90 percent efficient. That means the charger wasted 10 percent of energy, turning it into heat.
This doesn’t square with Eric Ravenscraft’s story at OneZero. He says:
“Charging the phone from completely dead to 100 percent using a cable took an average of 14.26 watt-hours (Wh). Using a wireless charger took, on average, 21.01 Wh.
That comes out to slightly more than 47 percent more energy for the convenience of not plugging in a cable. In other words, the phone had to work harder, generate more heat, and suck up more energy when wirelessly charging to fill the same size battery.”
Ravenscraft found how he positions the phone on the charging mat makes a huge difference. And he found it hard to line things up to get the best results.
Wireless charging hit and miss
Wireless charging can be hit and miss. There are mornings when I pick up my phone and discover that it didn’t charge overnight.
The phone only has to move a millimetre or two for that to happen. It is so sensitive that I can open a desk drawer or type on my keyboard and the phone moves away from a charging position.
In his story Ravenscraft reveals a wireless charger consumes a small amount of power when it isn’t charging a device.
All up, wireless chargers waste a lot of power. It may only be a tiny amount per person, per charger, but multiplied by millions of users around the world it adds up to environmental damage.
In my earlier story, I noted that wireless charging is handy, but plugging in a cable is hardly a big deal. You get almost no advantage for what, in aggregate, is a big environmental cost.