Magsafe, Qi2, NFC… Perhaps you have already come across these names during your quest for the best wireless charger. The entire electronics industry has begun to adopt this technology in recent years, presenting it as a practical alternative to wired charging. And while it is true that wireless charging has some serious advantages (it is notably less visible than its wired counterpart), its disadvantages should also make you think twice before throwing your phone on its base.
Wasting energy and wearing out your battery
Depending on the model, a wireless charger can consume, over a day, up to 180.9% more energy than a good old “classic” charger. These figures come from measurements carried out by iFixit repair specialists and more precisely from a test of the Wireless Charging Platform, the wireless charger made by Tesla. Over 24 hours, with a charging phase of 7 hours (to simulate a night of charging), the Tesla machine consumes 66.3 watt-hours (Wh) compared to 23.6 Wh for a conventional wireless charger.
Worse, the device has the bad taste of somewhat frying the batteries it recharges. In tests conducted by iFixit, the battery of an iPhone 15 Pro reached 40°C over extended periods. Remember that excessive heating can prematurely damage a battery, reducing its lifespan and therefore encouraging us to renew our devices (which weighs heavily on the digital carbon footprint).
But Tesla’s charger isn’t the only one. If it is certainly the worst student passed through the iFixit labs, wireless charging in general is much less economical and ecological than wired charging. During tests carried out in our labs in 2018, we already noticed that not all wireless chargers are equal.
Wireless charging is finicky
An official MagSafe (Apple) charger, for example, consumes 30 Wh over a day, while an entry-level charger from Amazon can consume up to 57.9 Wh for similar use. A difference which is mainly explained by the frequent misalignment of the coil of the smartphone and that present in the charger. Only MagSafe and Qi2 chargers ensure good alignment thanks to magnets present around the coils. Each additional millimeter that separates the two coils (if your phone is equipped with a case, for example) reduces the efficiency of wireless charging.
Even taking into account only the 0 to 100% charging phase of a phone, wireless chargers consume more energy than wired products, ranging between 28% and 106% additional consumption, according to iFixit . Wired charging is obviously not perfect either, with some energy being lost at various stages of the process, but it is undoubtedly the most economical and environmentally friendly solution available today.