Yeah, this definitely caused me to raise an eyebrow. UPS covers brown outs and obviously the occasional temporary power outage. All those drives spinning at full speed suddenly coming to a grinding halt as the power is suddenly cut, and you're quibbling over a paltry additional 10 watts? I can only assume that the data is not that important.
As part of resilience testing I've been turning off our 24 drive backup drive array daily for two years, by flicking the wall switch. So far nothing happened.
