“Turn off the lights! You’re wasting energy!” - It used to be every parents mantra. But I don’t hear it as often anymore. I try to remind my kids - but there are so many other things to nag them about. In picking my battles, this one often gets left behind.

Lately, I have been wondering how much it really costs to leave those lights on (environmental impact aside). There is an excellent explanation at the U.S. Department of Energy.

The bottom line is this:

• One 60 watt bulb burning for 1 hour translates to .06 kWh (kilowatt-hours).
• On your electric bill you are charged a certain rate per each kWh used. (On my last bill this was made up of a bunch of different rates for generation services and delivery services. When I added all these together my total rate was about 18 cents per kWh)
• To leave one 60 watt bulb on for 1 hour costs me about 1 cent (.06 kWh x 18 cents = 1 cent)That doesn’t seem like a lot.

  But I rarely have just one bulb on. In my average sized kitchen I have 10 recessed lights. If I left these on for 8 hours a day (we are in the kitchen a lot!) for a month, it would cost about 24 dollars. When I consider all the other rooms in the house the costs just add up.

  To make the numbers more real, count every light bulb in your home. For this example just assume that it will cost you 1 cent per light bulb for each hour it is on, then do the math.

  I will definitely be scouring Home Depot this weekend for more energy efficient options. And “don’t forget to turn off the lights!”