Charging M1 MBA with 20W charger?

[Scarrus]

Has anybody tried to use a 20W charger as their main charger for an M1 MBA and if so is it enough to at least use it plugged in under load without draining the battery, maybe even charge it a bit in the mean time?

 

[russell_314]

Has anybody tried to use a 20W charger as their main charger for an M1 MBA and if so is it enough to at least use it plugged in under load without draining the battery, maybe even charge it a bit in the mean time?

I did on my M2 Air and it was fine for web browsing and just normal use. It kept it at 100%. Of course I'm sure if you're doing video editing or running benchmarks it would need more than 20 watts.

I would caution using it as your everyday charger though. I'm no expert on electronics but maybe it could have a negative effect on the battery after a while. I don't think using it occasionally wouldn't hurt it though.

 

[brucewayne]

I have been using a Ryobi power source (which according to my USB-C power meter puts out 27.3W) on a 2019 i5 MBP that came with a 61W charger. It will run normal tasks (youtube, web surfing etc) while charging the battery (albeit slowly).

An M1 MBA (which normally comes with a 30W charger) should be much more power efficient and will likely do as well.

Also, considering that my iPhone 12 is now in conservation mode (charging the battery slowly in the evening), it seems like charging slow shouldn't hurt your battery long term.