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Is 20w adapter enough to charge and operate M1 MacBook Air?

Sydde said:
Does anyone offer this:
a hub, with a male usb-c lead going to the macbook, with a power cord to a brick, such that the hub can supply enough juice to charge/maintain the book while also providing power to the hub-connected devices that are demanding it (e.g., a trackball or iPhone, but not power for a printer)​


That is what I want.
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You should get a charger, which is about 20-30W more powerful than what laptop demands.

For Macbook Pro get a 90-100W charger and a hub, which supports 100W charging.
For Macbook Air get a 60W charger and pretty much any hub should work.

This is, if you need optimal charging even when laptop is working under load. Otherwise even original adapters will probably work most of the time.
I also suggest brand names for hubs, like Anker.


On a personal note I find it kinda stupid that these hubs have such a high energy consumption, while a whole laptop runs on barely twice as much power.
 
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I left my M1 MBP connected to a Windows based laptop via USB-C to USB-C cable overnight a round two months ago. The Mac was down to roughly 20% when I went to bed, but was charged to 100% when I checked it the next morning. It probably took the majority of the night to charge it, but the fact that it charged off another laptop that way humored me.
 
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acidfast7_redux said:
Why on earth would I carry a huge charging brick. It's an MBA and it's travel footprint should be small.

People proposing huge bricks have lost the plot entirely.
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Alternatively, some need ot charge a computer, iPhone and iPad or watch and having one brick to bind them all is better than 2 or 3.

Sydde said:
Does anyone offer this:
a hub, with a male usb-c lead going to the macbook, with a power cord to a brick, such that the hub can supply enough juice to charge/maintain the book while also providing power to the hub-connected devices that are demanding it (e.g., a trackball or iPhone, but not power for a printer)​


That is what I want.
Click to expand...

Same here. I have a Kensington Nucleum which is nice but even with a 100W charger won't run an external HD.
 
killerdesign said:
Then instead of spending $50 for Belkin charging brick getting a HomePod mini sounds as a better option to get an extra charger for MacBook Air.

However, I doubt it will charge a MacBook Pro: even though it has more or less same specs and a slightly bigger battery, for some reason Apple ships it with a 61w power adapter.
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Own the M1 MBP, it charges perfectly find although slower. You have to remember while it's shipped with a 60W charger instead of a 30W with the air it doesn't mean the power consumption is doubled. It essentially still uses the same chip and hence uses the same load. Also keep in mind these chips in power consumption are the same as iPad/iPhone, so it's a lot lower than traditional intel MacBooks.

The only reason why they ship a larger charger is over head when you do use the MacBook on load, the air will throttle and cap the performance at around 80% to prevent overheating while the Pro can run full load continuously. Hence to prevent the laptop losing charge whilst on full load, they ship with a larger charger.

Monitoring using coconut battery just doing regular tasks at full brightness the most the laptop ever drew at a given time is 8W. This is even lower if you run it at half or zero brightness. Hence a 20W charger is perfectly adequate, if you don't the slow charging, the percentage definitely doesn't go backwards, more like 1% every 2-3 minutes
 
It’s not like the supplied USB-PD 30 Watt charger is large by any means. I do have this 65 Watt GaN charger for comparison, which is slightly smaller.

I have to ask to why you would use a slower charger?

IMG_3796.jpg
 
Pressure said:
It’s not like the supplied USB-PD 30 Watt charger is large by any means. I do have this 65 Watt GaN charger for comparison, which is slightly smaller.

I have to ask to why you would use a slower charger?

View attachment 1867118
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You want a slower charger because it's like a third of the size of the supplied MacBook charger. Look at the size of your iPhone charger, it's about that size which is much more convenient to carry around if you are on the go.
 
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It will work. It will just be slower. I charged my MacBook Air up the other day with the 20W USB C charger that came with my iPad mini. I used it for a while powered from the charger and it was fine.
 
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Jsee said:
You want a slower charger because it's like a third of the size of the supplied MacBook charger. Look at the size of your iPhone charger, it's about that size which is much more convenient to carry around if you are on the go.
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This. Just being able to grab a 20w iphone charger + 1 usb cable that takes care of both the macbook air m1 and iphone helps to save some backpack weight and space.

1. I've noticed that my Xiaomi power bank can charge the macbook air while I'm using the air, extending my outdoor usage time.
2. With the new macbook pro going back to magsafe, one would need to bring one more cable :p
 
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hunkster said:
This. Just being able to grab a 20w iphone charger + 1 usb cable that takes care of both the macbook air m1 and iphone helps to save some backpack weight and space.

1. I've noticed that my Xiaomi power bank can charge the macbook air while I'm using the air, extending my outdoor usage time.
2. With the new macbook pro going back to magsafe, one would need to bring one more cable :p
Click to expand...

Since the new MBP also uses USB-C it still can charge with a USB-C cable.
 
537635 said:
Guess no. Meanwhile it has become clear, that USB-C ports are limited to 100W. Only MagSafe goes to 140W. Weird choice.
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If they are PD 3.1 they can be designed to up to 240W. Apple may have limited them by design but the spec allows more than 100W. I agree if that is teh design it is a weird choice. Why not go to at least 140W; unless the concern is the lack of properly designed cables to handle the higher amperage?
 
acidfast7_redux said:
I don't see the reason to carry a power brick at all ... the machine will charge overnight with a phone charger and for me at least, lasts at least 10h screen on time. When I start travelling again (COVID), I'll just carry a USB to USB-C cable with me and charge at USB ports if I need to. But like I said, I'd have to be travelling at least 10-12h to need any kind of charging brick.

Otherwise, I'll buy one and leave it at the office.
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I don’t carry the OEM power brick when I travel(ed?). I use a small GaN charger about the size of a phone charger and charge the phone and laptop from that.
 
Just refreshing this thread since it has been since October 2021. I bought a couple MagSafe wireless chargers and want to use the newest Apple 20W USB-C charger since it is picky if you want full 15W charging for iPhone 13 lines.

From this thread, that charger will charge a MacBook Air 2020 with no issues when not being used and will allow charging while being used except, possibly, very high power demand tasks.

Also there is the upside as other posters mentioned that slower charging is better for batteries. The people with the longest lived iPhone batteries seem to recommend charging when it drops to 20% and then unplugging around 80%. These batteries appear to not like extremes or rapid charging which causes heat and degradation. Some really like using those old 5W original cubes to charge their iPhones with enough time.
 
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cdames00 said:
Anker’s got a new offering; 65w total output, or 45/20 if charging two devices..

www.amazon.com

Anker USB C , 726 (Nano II 65W) PPS Fast Charger Adapter, Foldable Compact Charger for MacBook Pro/Air, iPad Pro, Galaxy S20/S10, Dell XPS 13, Note 20/10+, iPhone 13, Pixel, and More

Model Number: A2666
www.amazon.com

the picture to show scale
View attachment 1817151
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It looks like a nice charger, but why limit to 45/20 with two devices? Why can't it do 30/30 so you could charge two MBAs or an MBA and a iPad Pro?
 
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Odessa said:
The macbook air is so efficient it can even charge with a 5W charger when idle (although extremly slowly)
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Wow, seriously? That’s interesting. Wonder how slow it would be with the 12 watt. Now I wanna do an experiment!
 
Works totally fine with the 20W charger. As other's said, it is so efficient it'll charge with 5W charger, question is at what minimum wattage will it NOT charge if you use it doing normal surfing activities (not hardcore gaming and editing).

I've been reading about battery health and it appears that the iPhone magic number appears to be 40% or into the 30s% then recharge to 80% using slow charge. On the Mac that I just let it charge to 100% - it doesn't come off the charger and get taken everywhere like my iPhone 13.
 
I forgot my charger today...then I saw my Dad's 20w iPad charger with his Samsung Galaxy USB-C cable next to it and thought "I wonder...". That it worked was quite satisfying.
 
Necro-thread I know but just in case anyone is searching this up in 2023 I use a 20w iPhone brick on my M1 Air exclusively. I also run a Basus USBC-cable with a wattage display. It may not be the most accurate meter but I've never seen it higher than 18W and that's with full screen brightness rendering Canon RAW files in Lightroom from an external SD drive. I guess it will dip into the battery a bit rendering 4k video if it's long but I've done short clips of maybe 5-10mins and haven't seen it.
 
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jptsr1 said:
Necro-thread I know but just in case anyone is searching this up in 2023 I use a 20w iPhone brick on my M1 Air exclusively. I also run a Basus USBC-cable with a wattage display. It may not be the most accurate meter but I've never seen it higher than 18W and that's with full screen brightness rendering Canon RAW files in Lightroom from an external SD drive. I guess it will dip into the battery a bit rendering 4k video if it's long but I've done short clips of maybe 5-10mins and haven't seen it.
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I'll necro this one too. FWIW, Eaton, an electrical systems company, says their 15 W non-PD USB-C outlet is not compatible with the M2 MacBook Air. However, I have confirmed that it can charge my 12" MacBook, albeit very slowly. If I'm using it to surf MacNN and look at pix in Photos, it maintains the charge and very, very slowly charges it too, like 1% every 5 mins or so. I suspect Eaton just means that while their non-PD 15 W will work, it's too slow to be considered a true charger for the MacBook Air. My Leviton PD 30 W outlet charges it much, much faster.

I put some more details and measurements of the Eaton non-PD outlet and the Leviton PD outlet here, along with some info on some other chargers and devices:

forums.macrumors.com

Charging MacBooks - PD vs non-PD chargers. Eaton says M2 MBAs are not compatible with 15 W non-PD chargers. Some tests inside (but not with MBA).

That 15 W (5 V x 3 A) Eaton USB-C outlet can maintain the charge on my 12" MacBook for the most part, but during usage it won't increase charge. A 30 Watt Leviton USB-C outlet with Power Delivery works much, much better. I've tested a bunch of different products now, with different chargers...
forums.macrumors.com forums.macrumors.com
 
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