Science Gift Ideas: Kill-A-Watt



Awhile back I blogged on, a black-background version of that purported to save energy by reducing the amount of light monitors needed to emit to display their page. Researchers confirmed this was true of old, obsolete CRT monitors, but flat screens used more energy to suppress white than display it.

Well, my Kill-A-Watt ($25) arrived in the mail awhile back, and it’s now official. My computer system, running dual flat-screen monitors uses 254 to 255 Kilowatt Hours of electricity to display Google on both screens, and 255 to 256 kilowatt hours to display Blackle on both screens. With both monitors turned off, my computer uses 142 kwh.

You know what else I found? My computer consumes 14 kHz when it’s turned off. After some troubleshooting, I found this was because I leave my speakers on, turning them off reduced my power consumption at this wall socket to zero when not in use.

The Kill-A-Watt is a handy device, and one I’ve returned to regularly in the last couple of months out of curiosity to see how changes to my computer affect its power consumption. It provides several different ways to measure consumption, including a clock that tracks total energy used.

The Kill-A-Watt has also made me a bit more energy conscious, and that’s why I’m recommending it as a gift. It’s a scientific tool that gives me a clearer understanding of how my actions affect the burden I place on the Earth, and the burden I place on my pocketbook when the power bill arrives.