15" MBP Battery Life during Presentations

[Hawkeye411]

Hello,

I have a 15" Unibody MBP, 2.53GHz, 4GB Ram
My battery rarely lasts longer than 2 hours.

When I'm teaching, I am connected to a digital projector, I have the screen brightness at the lowest setting and I am using the integrated 9400 video card. Bluetooth is off and I am connected to the Internet via WiFi.
My fully charged battery will only give me 2 hours of use in this situation. Does this sound "normal" from your experience?
Battery Info
161 Cycles
96% Health

Thanks.

 

[a4209797]

are you using powerpoint? with my i7 mbp powerpoint uses the nvidia card.

 

[GGJstudios]

Have you calibrated your battery to make sure that your readings are accurate? Calibrating a portable computer battery

 

[Hawkeye411]

I haven't calibrated for quite some time. I'll give it a try.