I guess I am a bit surprised. We lost power in my small town 30 minutes ago. Because I got tired of my ATT router rebooting at every electrical blip, I plugged it into my back up battery that I use for my desktops a few months ago. well, this MBA is receiving wireless signals and working just as fast as always. The house is dark, but my battery operated laptop is on the web because the router is plugged into a backup battery. I would have thought that the router would loose the wifi signal. This is pretty cool. Just wanted to share. I'm probably not in the right forum for this, but am typing on a maxed out 2015 MBA so I posted here. In the past when this happened, I would connect to my iPad or iPhone for a signal if necessary, but the surfing isn't nearly as good that way. Not sure how long this backup battery is gonna last though.