30 Chapter 2 Life with Your MacBook Pro
Using the MacBook Pro Battery
WhentheMagSafepoweradapterisn’tconnected,yourMacBookProdrawspower
fromitsbuilt-inbattery.ThelengthoftimethatyoucanrunyourMacBookProvaries,
dependingontheapplicationsyouuseandtheexternaldevicesconnectedtoyour
MacBookPro.
TurningofeaturessuchasWi-FiorBluetooth®wirelesstechnologyandreducing
screenbrightnesscanhelpconservebatterycharge,forexample,whenyou’retraveling
byair.Manyofyoursystempreferencesareautomaticallysettooptimizebatterylife.
Youcandeterminethechargeremaininginthebatterybylookingattheeightbattery
levelindicatorlightsontheleftsideofyourMacBookPro.Pressthebuttonnexttothe
lights,andthelightsglowbrieytoshowhowmuchchargeremainsinthebattery.
Important: Ifonlyoneindicatorlightison,verylittlechargeisleft.Ifnolightsareon,
thebatteryiscompletelydrainedandtheMacBookProwon’tstartupunlessthepower
adapterisconnected.Pluginthepoweradaptertoletthebatteryrecharge.Formore
informationaboutbatteryindicatorlights,seepage54.
Youcanalsochecktheamountofbatterychargeremainingbyviewingthe
Battery( )statusiconinthemenubar.Thebatterychargeleveldisplayedisbased
ontheamountofpowerleftinthebatterywiththeapplications,peripheraldevices,
andsystemsettingsyou’recurrentlyusing.Toconservebatterypower,close
applicationsanddisconnectperipheraldevicesnotinuse,andadjustyourEnergy
Saversettings.Formoreinformationaboutbatteryconservationandperformancetips,
gotowww.apple.com/batteries/notebooks.html.