So I wanted to get myself a Kill-a-watt. Being who I am, I wanted information regarding its accuracy, especially at low power draws. I found a comparison with a industry grade equipment (Fluke is about the best out there in handheld electrical meters). It’s not encouraging, so I thought about a more proper meter, but it’s not easy to find an actual power meter that is accurate at low loads, isn’t a hassle to install and doesn’t cost an arm and a leg.
What do you use? Am I overthinking it?
The problem is that it’s not just 15W; I merely used that as an example of how even just two “low power” devices can cause an effect that you can measure in euros rather than cents.