Wireless chargers are very convenient, whether you’re determined to minimize cable clutter or are simply tired of plugging in your phone every day. However, there is a hidden cost: your charger wastes electricity and that costs you money and time.
There are times when that convenience can outweigh any other factor. However, sometimes it’s better to find that USB cable. Here’s why wireless charging is a waste and when it makes the most sense to go the wired route.
Why does wireless charging waste electricity?
Basic physics makes it less efficient.
Wireless power for phones, headphones, and smartwatches revolves around inductive charging. The technology creates an alternating current (AC) within the charger coil, producing a magnetic field that sends power to a coil in your device. That AC electricity is converted to direct current (DC) and powers your hardware.
That process wastes electricity in multiple stages. You are converting from AC to DC and vice versa on the charger, from AC to magnetic fluxes and vice versa, and from AC to DC again on your device. And when the wireless charger produces AC at very high frequencies (around 140 KHz), the skin effect reduces the effective conductive area by moving the electrons away from the copper wire of the coil. That leads to energy being wasted as heat, part of the reason why your phone may feel hot after a charging session.
This also assumes that you have placed your device perfectly on the charger and that there is nothing else in the way. If you haven’t, you won’t get optimal speed. Charging formats like MagSafe and Qi2 solve this problem by magnetically aligning your device and its charger. However, even a thin casing can reduce efficiency by creating more obstacles for electrons.
A wireless charger consumes power even when you are not using it. Because it always has to be ready to charge, it constantly consumes a small amount of power, no matter what is happening. That draw tends to be small (iFixit I saw an average 0.2W), but many wired chargers turn off completely when not in use.
Wireless charging wastes money
You can save energy and the planet
All that wasted electricity results in significantly more power consumption than you would need for equivalent wired charging. The exact waste depends on the device, position and form factor, but even an ideal scenario with Qi2 (and its MagSafe equivalent) loses between 12 to 20 percent of power even before taking into account the always-on state of the charger. That volume grows by 25 to 40 percent for conventional Qi charging.
A typical USB-C cable charge loses only 5 to 10 percent of the energy involved.
The money you waste may not be dramatic, but it can add up. A 15W MagSafe or Qi2 charger uses electricity equivalent to running a 10W LED bulb for 24 days straight, notes iFixit. And if you live with other people or have multiple devices, that demand will increase.
As such, it’s best to stick with wired charging if you’re looking to reduce your energy bills. It is also kinder to the planet as it will reduce strain on the electrical grid.
Wireless charging wastes time
Plug it in when you’re in a hurry
Wasted electricity also limits possible charging speeds. Qi2 and the latest MagSafe chargers max out at 25W. You’ll see up to 100W, but that often requires brand-specific chargers with aggressive (read: noisy) cooling. As a general rule, wireless charging is slower than wired charging.
It’s easier to find fast wired charging. a google Pixel 10 Pro supports wired charging up to 30W with a compatible adapter, while Samsung Galaxy S26 Ultra Supports 60W. If you’re willing to use highly proprietary chargers, 80W to 100W is common on devices like the OnePlus 15.
That disparity affects loading times. A Galaxy S26 Ultra takes 15 minutes to reach 50 percent power at 60W, while a Qi2 pad will take about 33 minutes. If you forgot to charge the night before, that can make the difference between lasting through the workday and having to plug it in at lunchtime. Pull out a cable if you rarely have more than an hour to recharge.
Wireless charging is still okay, sometimes
This doesn’t mean you should give up wireless charging forever. A wireless charger in your car can save you valuable time when you’re already late for work, not to mention freeing up a USB port for a passenger. Wireless chargers for multiple devices can be useful when space for cables is limited. And if you’ve ever gotten snagged on a cable and sent your phone flying, you’ll know why wireless charging can be safer.
It’s important to remember that wireless charging comes at a cost and it might be worth taking a few extra seconds to plug it in. You could save yourself some headaches, even if the wired connection seems like a hassle at first.
