Increasing battery time of a Laptop.
Is there any method other than working with limited processor speed?
I bet, there is none. But, according to Fredrik Andersson, ‘Undervolting' (cutting voltage to the processor) the processor (the biggest power consumer in Laptop) may increase battery time of a Laptop substantially. He has given detailed instructions to how to do it.
Well, we all know that a device's power consumption remain un-effected because when you decrease voltage, its current consumption increases. Though Fredrik had claimed that he was able to save about 19% battery power without compromising performance, still, unless there were more studies made to prove this claim, this method will remain controversial.