Wireless charging in mobiles has a big problem: it needs almost 50% more energy than charging the mobile with cable

OnePlus 8 Pro has 30W wireless charging — here's how it works ...

Wireless charging is great until it stops, and an analysis of its efficiency reveals that this type of feature has a problem: Much more energy is wasted.

The Wireless Power Consortium itself has long warned of the inefficiency of wireless charging systems, but a new study makes it clear that almost 50% more energy is used when charging the mobile with a wireless charger compared to doing so with the charger with conventional cable.

The Qi standard is the best we have, but it is not very efficientBeing able to transmit power without cables is an old technological dream that has long become a reality. Wireless chargers that use techniques such as induction have long allowed us to charge our phones or smartwatches and make our life more comfortable, but they do not make it more efficient or cheap.

The Wireless Power Consortium (WPC) already warned years ago ( PDF ). In a study to evaluate the efficiency of wireless charging, they confessed that measuring this parameter was quite difficult because, in the first place, there was no standardized methodology that allowed to establish how efficient (or inefficient) a wireless charging system was.

Is it possible to transfer charge from one mobile to another ...

It is precisely for this reason that they set out to compare wireless charging technologies such as Rezence and Qi, which is currently the de facto standard in the industry. The first, Rezence, was a great implementation for charging multiple devices on the same surface at the same time, but its cost and efficiency didn't make it particularly desirable.

In this WPC study, it was concluded that the efficiency should be calculated as a spatial average, and after comparing different chargers it was clear that the efficiency of these technologies was very poor in the case of Rezence (39.6%) and mediocre in the case of Qi (59.4%).

Wireless charging makes us use almost 50% more energyThe data has now been validated by a study by OneZero in which it was compared how much energy was needed to charge a Pixel 4 from 0 to 100% using several wireless chargers and comparing that average data to the energy needed to charge it with its cable charger.

The result was overwhelming: on average, wireless charging used 21.01 Wh, while wired charging used 14.26 Wh. That means that wireless charging used 47% more energy "for the convenience of not connecting a cable" than actually if you do connect, but instead of connecting to the mobile you connect it to the wireless charging base, of course.

"In other words," concluded those responsible for the study, " the phone has to work harder, generate more heat and collect more energy when it is charged wirelessly to fill a battery of the same size."


In that experiment, something that was also observed in the Wireless Power Consortium study became clear: the position in which you place the mobile on the wireless charger affects charging efficiency.

Indeed, this impact is not particularly worrisome for a single user: the study we carried out in Engadget revealed that the approximate investment we make to charge the mobile is barely 1.5 euros per year.

The problem, of course, arises when we look at that on a macro scale. As those responsible for iFixit said when consulted by OneZero: " if the more than 3,000 million smartphones that are in use needed 50% more energy to do so, the thing would end up adding a large amount. So, this is a problem social, not personal. "

Post a Comment