Calculating laptop power consumption
210W DC is worst case weak battery and full screen brightness at 100% CPU.  Then efficiency I expect is 85% max so AC input current is for computing  breaker capacity. 

You can expect laptops use  10% bestcase  of this power on very dim displays with charged batteries and 100% worst case.  Try 50% or better and expect short life.   Laptop consumption varies greatly from 65W Max types to gamer power hogs.