I think that it doesn't matter how much energy it wastes provided you'll only use it for your laptop. 1/(1-.45) * $1 a month is still negligible compared to th

I think that it doesn't matter how much energy it wastes provided you'll only use it for your laptop. 1/(1-.45) * $1 a month is still negligible compared to the pain in the ass it is to get it plugged in every time you want to use it. At this point it's not meant for lighting a house or powering a TV.