Has anyone found and documentation on the efficiency of UPS inverters? I have a large server UPS that seemed like a good idea at first to use as an inverter but that was a bust because it didn't support cold starts (starting up off batteries). Glad it was free. I also wondered how much extra power it used on communications & monitoring? The one I have looks like this
. Since they are typically used only long enough to shut down your computer then I wonder if they try to make them efficient. No load draw could also be high. The one I have uses a large transformer which I suspect could hurt efficiency.