Dilby replied on 23/12/2021 14:06
Posted on 23/12/2021 14:06
Hi all - I have just got a new laptop (macbook pro) and in the new year plan to do a bit of working from my van. I have a 100ah leisure battery and plan to upgrade my system, but I'm really struggling with the maths on all the electric requirements and was hoping someone could help.
The charger for the laptop states:
Input 100-240v 2.0A, Output 28v 5A or
20.5 v 5A or 15v 5A or 9v 3A or 5.2v 3A
I hope I'm right in assuming that the most useful unit to end up with are the watt hours, and I know that a 100ah battery will give 1200wh (although it's lead acid do in reality about half).
But I don't know how to work on the real world watt hours for the macbook as it gives so many voltage examples. I'll be on12v so I thought just go with maybe 4A as that's inbetween the 15 & 9A examples, but the watt hour calculation on this really changes; for example, 240v @ 2A is 480 watt hours while 5.2v @ 3A is 27 watt hours.
I hope I haven't confused people more than I am myself, and thanks for any help!
Dilby
Motorhomer