My MacBook Air's Battery Life :-)

TheBigK

Well-known member
Just spotted something totally amazing on a 13" MBA i5 machine running OS X Mavericks -

MBA-13.webp
 
Mine 15" 2012 rMBP doesn't get pass 4 hours on 70% brightness...

Try a cycle - that should fix it. Let it run completely flat then charge it all the way up without using it - I find its best to do it a couple of times. Should be back up to at least 7 hours after that.

If its still not fixed, take it into an Applestore or phone them and get it fixed :) Should be free if you're in the UK/EU as it would fall under it not lasting a satisfactory length of time and is covered even outside of Applecare
 
I've got one of the new MBA's with the Hazwell chips. It's pretty nifty - seems a tad slower than my older one (which my lucky daughter got for a holiday present!), but now I use it 100% not plugged in.

That is, the battery lasts me about 3 days of my normal laptop use, so I don't even bother topping it off or plugging it in until empty. It charges very fast also.

All in all, a good compromise between batt life and performance - and it makes it a true laptop to not have to plug it in very often!
 
Try a cycle - that should fix it. Let it run completely flat then charge it all the way up without using it - I find its best to do it a couple of times. Should be back up to at least 7 hours after that.

If its still not fixed, take it into an Applestore or phone them and get it fixed :) Should be free if you're in the UK/EU as it would fall under it not lasting a satisfactory length of time and is covered even outside of Applecare
That's not the problem if the laptop, that just how it works. The 15" Retina display from 2012 has external graphic card that takes. Lot of juice. In addition, Apple claims up to 7 hours battery with these machines, but that's with 50% brightness, Safari and Wifi enabled. Since I use chrome, it takes a little bit more power, but still 4 hours is a shame (and that's the average for these machines).
 
That's not the problem if the laptop, that just how it works. The 15" Retina display from 2012 has external graphic card that takes. Lot of juice. In addition, Apple claims up to 7 hours battery with these machines, but that's with 50% brightness, Safari and Wifi enabled. Since I use chrome, it takes a little bit more power, but still 4 hours is a shame (and that's the average for these machines).

I own the 2012 15" rMBP - my battery life has no such issue, hence why I commented. 4 hours is not in any way average for this machine. I regularly get 7 hours with WiFi, Sound, Photoshop, SublimeText, Chrome and Xcode all open at once - 8 hours if I turn wifi off and only use it for light work. That was on Mountain Lion too - on Mavericks it should last a bit longer due to the app nap feature.

As I said, try a cycle - if you're still getting 4 hours its a fault. Also, the graphics is little to do with it - when on battery power it switches down to the integrated graphics unless you've disabled that. Even then I can still get approx 6 hours, as can everyone else.
 
I own the 2012 15" rMBP - my battery life has no such issue, hence why I commented. 4 hours is not in any way average for this machine. I regularly get 7 hours with WiFi, Sound, Photoshop, SublimeText, Chrome and Xcode all open at once - 8 hours if I turn wifi off and only use it for light work. That was on Mountain Lion too - on Mavericks it should last a bit longer due to the app nap feature.

As I said, try a cycle - if you're still getting 4 hours its a fault. Also, the graphics is little to do with it - when on battery power it switches down to the integrated graphics unless you've disabled that. Even then I can still get approx 6 hours, as can everyone else.
I did many cycles, and that's the average battery life when you are on 80% brightness. What brightness you are using? I can't use anything below 70%. Every 10% increase from 50% = less 30min battery.
If you use Chrome instead of crappy Safari, same thing.
 
I did many cycles, and that's the average battery life when you are on 80% brightness. What brightness you are using? I can't use anything below 70%. Every 10% increase from 50% = less 30min battery.
If you use Chrome instead of crappy Safari, same thing.

Not sure on actual brightness settings as it doesn't show a percentage as default, but I'd say at least 80%. Seriously, you have something wrong if you're getting 4 hours regardless of brightness level.
 
Not sure on actual brightness settings as it doesn't show a percentage as default, but I'd say at least 80%. Seriously, you have something wrong if you're getting 4 hours regardless of brightness level.
I've been there, and they told me everything is fine. My battery is about 90% health and
Charge Information:
Charge Remaining (mAh):7395
Fully Charged:Yes
Charging:No
Full Charge Capacity (mAh):7468


If you go to the biggest battery thread on Mac Rumors you would see that 4 hours is pretty common for the 15" rMBP.
80% brightness is about 3 bars before the max.
 
You're saying over 18 hours is "very possible" at almost idle? Really?

The time remaining is a constantly changing estimate. It's based on a number of factors, including current workload, and settings on the Macbook Air itself. Apple's estimates are based off various elements like CPU cycles, screen brightness, inputs, and power draw on ports. It is all relative based on what you are doing.

It's no different than your vehicle's estimated distance achievable on remaining on a tank of gas. If you're driving 40 mph, you'll get one estimate of the distance remaining. You would get a different estimate if you were driving 60mph, 80mph or 100 mph. Because your speed is constantly changing, the actual distance remaining on a tank is impossible to accurately estimate. So it is with battery life from a charge.
 
The time remaining is a constantly changing estimate. It's based on a number of factors, including current workload, and settings on the Macbook Air itself. Apple's estimates are based off various elements like CPU cycles, screen brightness, inputs, and power draw on ports. It is all relative based on what you are doing.

It's no different than your vehicle's estimated distance achievable on remaining on a tank of gas. If you're driving 40 mph, you'll get one estimate of the distance remaining. You would get a different estimate if you were driving 60mph, 80mph or 100 mph. Because your speed is constantly changing, the actual distance remaining on a tank is impossible to accurately estimate. So it is with battery life from a charge.

Yeah I know all of that. But 11 hours on a 60% charge implies that under the same conditions, (i.e. virtually idle) a 100% charge would give something like 18 hours, assuming it's roughly linear (which it has to be or the estimate is meaningless). Can the Air really do that?
 
I've been there, and they told me everything is fine. My battery is about 90% health and
Charge Information:
Charge Remaining (mAh):7395
Fully Charged:Yes
Charging:No
Full Charge Capacity (mAh):7468


If you go to the biggest battery thread on Mac Rumors you would see that 4 hours is pretty common for the 15" rMBP.
80% brightness is about 3 bars before the max.
Meh I give up.

I'm an active member on MacRumors - I know people had issues when they came out and they were resolved by replacing the battery via Applecare (IIRC there was a few faulty batches). I know for a fact it can do 7-8 hours with heavy use as both myself, and a colleague have the same machines.
 
Meh I give up.

I'm an active member on MacRumors - I know people had issues when they came out and they were resolved by replacing the battery via Applecare (IIRC there was a few faulty batches). I know for a fact it can do 7-8 hours with heavy use as both myself, and a colleague have the same machines.
Then you macbook is special:
http://www.anandtech.com/show/6409/13inch-retina-macbook-pro-review/11

for whatever you describe, Anandtech got 3.5 hours.
Again, if your brightness is anything close to 50%, then yes, I also get 6-7 hours battery life. But in my opinion it's not usable at this rate, so I work most of the time at 70-80%. In addition, if you use Chrome, it has a triple battery impact than Safari, so if you use Safari, then here is the difference as well.
 
Then you macbook is special:
http://www.anandtech.com/show/6409/13inch-retina-macbook-pro-review/11

for whatever you describe, Anandtech got 3.5 hours.
Again, if your brightness is anything close to 50%, then yes, I also get 6-7 hours battery life. But in my opinion it's not usable at this rate, so I work most of the time at 70-80%. In addition, if you use Chrome, it has a triple battery impact than Safari, so if you use Safari, then here is the difference as well.
It's not special. Read the review (the correct one: http://www.anandtech.com/show/6023/the-nextgen-macbook-pro-with-retina-display-review/16). The test is done on 100% brightness using pretty strong loads not described in what I said I do. Their test that came out at 2.33 hours was with a 1080p movie playing in a loop, a 1mbps download, the dgpu turned on, 10-second web page refreshing, flash enabled, etc.

I dont have flash enabled, I have brightness probably around 80%, I am not playing a movie on a loop and I'm not running a constant download. The dgpu setting on my machine is left in its default state, so it switches down to integrated graphics.

That right there is why despite the fact that I have chrome, photoshop, xcode and sublime open - the battery life lasts. It's about being sensible. You dont leave flash on for one thing - that's a HUGE battery killer.
 
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