Who among us would not say “yes” to smaller laptop power bricks and longer battery life? Well, read on and see if you really are a “yes man”.
We are all used to laptops with large power bricks which sit there waiting to serve power to our laptops regardless of the workload we throw at it. So it is probably no surprise that these power bricks are mostly under-utilized and waste energy.
According to Wen-Hann Wang (director of circuits and systems research at Intel Labs) a 65 watt power brick typically only needs to deliver an average of 17.5 watts.
Wang’s ingenious solution is to place a capacitor between a 10 watt battery or power brick. Once charged the capacitor takes care of power requirements above 10 watts. The capacitor situation apparently allows for 90% of the battery to be used for chemical reaction and 10% to be used to deliver power. Current batteries typically use 33% of the battery to deliver power.
The benefit is smaller, lighter power bricks and batteries as well as increased battery life – but what happens when the system demands power above 10 watts and the capacitor is fully discharged?
The answer is that power management will kick in and lower the processor frequency so that it consumes less juice. That is the trade off, and for many usage scenarios it doesn’t sound too bad at all.
Power users though will need to look at higher end products to satiate their need for limitless on-demand compute power …