There's no reason to believe KES boosts the voltage at night, and the daytime load of air-conditioning is MUCH greater than that of lighting at night. Besides, you could very easily verify your theory with a voltmeter. The sizzling you hear near the poles supporting high-tension lines is bleed-over, small-scale arcing, as relative humidity increases as the air temperature decreases... similar to what is more pronounced on the rare foggy days we have. And it's exacerbated by built-up salt residue on the insulators. Yeah, we'd like to think the electric utility would have a for-sure reason for every outage, but it's not always possible. And although we grumble and gripe every time the power goes out, they've come a LONG ways since the 70s and early 80s. To KES' credit, they've contracted with outside companies to do a huge amount of much-needed upgrades, replacement of lines and poles throughout their service area, etc.

15 minutes of no power is nothing to you, but we have to come back to our business and manually restart our computers so our business can continue. When I am out of town, I have to call in someone to do that for me -- so to me, it's not "nothing."