I picked up a Kill A Watt electricity meter today. Over the next few weeks, I will use it to determine where I am using the most energy and identify ways of cutting back. Smarthome has the best price, but I was impatient and picked it up at a local retailer for $40. That seems crazy, I know, but I live in Canada, and it would have taken a week to arrive, plus at least $10 in shipping.
The Kill A Watt electricity meter is very simple to use. You just plug it into the wall, then plug whatever you are measuring into the Kill A Watt. It shows Volts, Amps, Watts, VAs, Hz, PF and kWh.
For steady loads, you can simply take the number of Watts consumed and multiply to determine your running cost. More specifically:
My Lenovo X61 laptop, for example, draws a steady 30 Watts when running from a Kensington Universal 70W AC/DC power supply (it is running Windows Vista in High Performance mode). Based on my current electricity cost of $0.131 per kWh, it costs me $34.43 to run it 24 hours a day for a year.
The Sony Wega TV (tube) in my basement doesn't draw a steady load; the instantaneous power consumption in Watts ranges from 160 Watts to over 220 Watts. To determine average power consumption with a variable load, you need to use the kWh reading for cumulative energy consumption along with the built-in timer. Based on a couple of hours measurement, my TV consumes an average of 175 Watts, so it costs me about $200 a year to run it 24 hours a day; a more reasonable 5 hours a day costs me $42 a year. Note to self: Make sure the kids turn off the TV when they are finished watching.
Stay tuned for more measurements. Next on my list is the home theater, which includes a 60" DLP TV, Receiver, PlayStation and more, followed by my home office.