MBA battery time

I have a 2010 MBA and a 2011 MBA both on Lion.

I have noticed that the battery time left always seems well below the quoted 7 hours Apple says.

Now real running time might be 7 hours...just battery meter never says 7.

When I was on snow leopard with the 2010 MBA I could see 7, 8 or sometimes 9 hours.

Right now I am at 90% and it says 5 hours.

Is this normal?

 

That puts your projected total battery time at 5.5 hours. It depends on what you're doing. You can set the thing to encode a video and kill of the battery in 45 minutes. 3d game and you maybe get 75 minutes. Full screen flash video, maybe 3 or 4 hours. Other types of video depends on whether it's GPU accelerated. In general, browsing the web with flash off at reasonable brightness, close to low, you should pull 7 hours.

 

Just lowering the brightness and turning the keyboard backlight off my "battery time" went from 2:30 to 3:28... @50%

I never thought it would be that extreme...

Greetings
Julian

 

The estimates are usually quite off anyways... don't put too much trust in them.

 

typically you get less then what is estimated not more. on all the machines i have and i have several macs they always over estimate whats left. not under.

lion still needs alot of optimizations to get the kind of battery life leopard does.

 

Try to reset the SMC and calibrate the battery, you'll find that the battery estimates will change drastically if you haven't done it in a while, especially if you upgraded from SL to Lion.

 

hm... sounds interesting What is SMC?

Greetings
Julian

 

Intel-based Macs: Resetting the System Management Controller (SMC)

Apple Portables: Calibrating your computer's battery for best performance

 

THX

(10 char)

edit: how do I know it worked?

 

just wait and see...

 

There is nothing wrong with my MBP at the moment. Running on Lion. I've had it for 2 years now and never did a SMC reset. Should I even bother to do one? Or would that do more harm than good?

 

if your not having any problems associated with the battery or fan control and other things the SMC handles... I see no reason to reset it.

 

I guess I am pushing the wrong buttons... looks like a normal boot up to me...