I picked up one of these Kill-A-Watt units awhile ago from Amazon and started doing experiments with it. Well, time went by, the Kill-A-Watt sat in my toolbox, and other things took priority. Now, I’m looking back on it and have decided to have another go at this.
Step One: Calculate your cost per kilowatt-hour
This is fairly simple. Just take your electric bill, find the total amount of energy used (in kilowatt-hours, and divide your bill by it. This isn’t going to give you your exact cost per kilowatt-hour; instead, it will give you your cost per kilowatt-hour with your fixed costs figured in. Less accurate, but a better overall idea how much your power usage is costing you.
Once you have your cost per kWh, enter it into the box below to see how much all of the tested appliances would cost you.
Step Two: The data
|Keurig coffeemaker, 1 large cup||0.04|
|Small Holmes air purifier, speed 1, per hour||0.024|
|MacBook Pro (17″, 2007, 2.4GHz), per hour, running XBMC, movie playing||0.05|
|MacBook Pro (17″, 2007, 2.4GHz), per hour, running XBMC, idle||0.031|
Step Three: Check back
I’m going to keep testing random things. Check back often for the changes.