How long can I expect my laptop to run from the power stored in the Power Pack or battery?
There are many power packs on the market but most have batteries that hold around 20- 60 Ah (amp hours). These are small power packs that are designed to be portable. If for example, the power pack you are using has a 20 Ah, 12 V battery, the capacity is about 240 watt hours, give or take. We determine this by multiplying 12V x 20 Ah = 240 Watt hours. What this means is, that if you plug a laptop that required 60 watts to run. You simply divide 60W รท by 240 Watt hours = 4 hours of power. There are several factors that determine how long a battery will last. If the draw is high, like a blender drawing 300 watts, it will last a short time – perhaps 20 minutes. If it is a very small power draw like a compact fluorescent light bulb, it may last up to 15 hours.
