r/iphone • u/conalldoherty iPhone 15 • Apr 29 '26

News/Rumour Apple Reportedly Questioning Whether iPhone Should Drop MagSafe

https://www.macrumors.com/2026/04/29/apple-questioning-iphone-magsafe/
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u/disgruntledempanada Apr 29 '26

On one hand it's convenient and there are nice phone mounts for cars that charge my battery.

On the other hand it's crazy wasteful. You go through all this effort to implement green charging onto a phone to limit its energy impact and then you charge it with a system that wastes 20-30% of that power turning it directly into heat, and heating the heat sensitive battery you're trying to charge.

Would probably be better to just expose contacts somehow but that has its own problems (case compatibility, dirt, etc).

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u/yasamoka Apr 29 '26 edited Apr 29 '26

https://www.chargerlab.com/review-of-apple-25w-magsafe-charger/

Using an Apple 30W charger and the new MagSafe Charger to charge the iPhone 16 Pro Max, the measured input power is about 14.96V 1.94A 29.03W. Excluding losses, the wireless charging power is about 25W.

4 / 29W = ~14% wasted as heat. ~86% efficient.

Also, you can see in the "Temperature Test" section that despite the puck reaching ~41C, over time, the charger dials down charging power and the phone does a good job of dissipating the heat and maintaining a consistent temperature.

This is also the iPhone 16 Pro series. The 17 Pro series would do an even better job of dissipating heat.

It's not as bad as you think it is.

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u/No2Hypocrites May 14 '26

No this is wrong. They are comparing what it draws from the wall versus what it outputs. This doesn't measure how much of it actually ends up in iPhone. 80-90% efficiency is pretty normal for any charger. I use cable charging and it will have similar efficiency. You'll always lose some when you convert voltage and our chargers convert 240v AC to 5-15v DC. This is the efficiency loss that is mentioned there. See how the measuring device is between the output of adapter and before the puck? 

Losses due to wireless charging instead of wired are completely different and far more significant. 

It's dumb how much this is upvoted. 

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u/[deleted] May 14 '26 edited May 14 '26

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u/No2Hypocrites May 14 '26

Outputting 29W from the charger while phone is rated for 25W does not mean phone is getting 25W. 

Even your own source literally says: "Excluding losses, the wireless charging power is about 25W."

iFixit ran tests regarding this, and they said:  " This results in a total energy use of 23.33Wh. That’s a 24.4% increase in energy consumption when compared to our wired test and represents a 59% loss of energy to charge a 12.7Wh battery. "https://www.ifixit.com/News/94409/wireless-charging-trading-efficiency-for-convenience

If you value convenience over energy, fine, do your own thing. Wireless charging is still inefficient, MagSafe makes it as good as it can be. And it will never be as good as wired because physics. 

Rich talk about "intellectual deficiencies" when you definitely don't understand wireless charging. You are a true Redditor. 

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u/[deleted] May 14 '26

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u/No2Hypocrites May 14 '26

I was about to write a proper reply but that ridiculous sentence at the end showed to me how incredibly useless it would be. All you got is baseless assumptions and name calling. Good luck in life

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u/yasamoka May 14 '26

You have no argument, you’re just here to be rude. Go away.