Most appliances work well and long enough to get your money back in returns, and in the spirit of saving even more money, appliance companies have built machines they advertise as energy efficient. You know, the ones that read “Energy Star” on them. The ones with the giant yellow tag you can’t miss, slap stuck to the top or front of the appliance or hanging off a control knob.

What perhaps you didn’t know is that these savings are based on national averages and not specific to the machine itself. For your benefit, there is a formula you can use to calculate the actual energy savings on the machine you want to buy. Whether you use the formula to help you save money, or you need to reinvigorate your trip to the appliance store with an intriguing yet easy mathematical challenge, this formula will help you better understand how energy savings are calculated. These are three things you need to do before using the formula:

• Estimate the machine’s daily run time. Base this on the run time of your current appliances. Refrigerators average 8 hours per day.
• Know the appliance’s average wattage. This information is usually found on the appliance. You can also find this information in a quick internet search.
• Look at your energy bill and find out many cents you pay per kilowatt.

The Formula

Here’s how you calculate the costs. This formula can also be found on TwoCents.LifeHacker.com...

1. Calculate the daily energy consumption:
(Wattage) x (hours used per day)
Divide the answer by 1,000

2. Calculate the annual use:
(Daily energy consumption) x (number of days the appliance is used per year

3. Multiply #2 by your energy cost.

Use this formula for your next Energy Star appliance purchase or on your current appliances to see how much they’re costing you. It’s simple to use, and the accuracy will help you pinpoint budgetary items helping you better manage your finances.

Here’s a Formula to Calculate How Much an Appliance is Costing You