How holiday decorations can affect your energy bill

In the 1989 movie National Lampoon's Christmas Vacation, decorating for Christmas takes on epic and rather funny meaning. In one of the movie's most famous scenes, Clark Griswold (played by Chevy Chase) decorates his house's exterior with 25,000 twinkle lights. They fail to work at first because he accidentally wired them through his garage's light switch. When the lights finally turn on, they temporarily cause a citywide power shortage and chaos for his neighbors.

Of course, a mere 25,000 lights dim compared to the Dutchess County, New York display with 641,695 lights choreographed to 252 songs. Created by the Gay family, this incredible display went live the day after Thanksgiving 2019. Amazingly, their recent electric bills were only about $350 per season, thanks to LED lights.

For more than 40 years, Mike Ziemkowski of Sherman Oaks, California, has been hanging thousands of lights, displays, and custom-made animatronics. He racks up a couple hundred dollars more than usual on his electric bill during the Christmas season but said the bill would be higher if not for LED lights. Indeed, electricity costs are something homeowners need to consider when decorating for the holidays. These stories and many others beg the question, how much electricity does a string of Christmas lights use?

Christmas light wattage

How much energy a light bulb uses depends on the type of light bulb. A 100-count string of incandescent mini lights is 40 watts, while the same count of 5mm electric LED string lights is about 4.8 watts total. LEDs use up to 90% less energy than comparable traditional light strings. LEDs are smart Christmas lights because while they cost more on the front end, they're energy-efficient and offer the following additional benefits:

LEDs vs. traditional Christmas lights

Whether you're looking for Christmas lights for indoor or outdoor use, mini lights or C7 bulbs are a good choice. Ceramic C7 bulbs measure a little more than two inches with the base. Mini lights come in standard strings of 100, while C7 candelabra-base bulbs typically come in a string of 25. Considering it takes 700 mini lights to decorate a 7-foot tree, 1,000 for a 10-foot tree, and as many as 2,000 for a 12-foot tree, the cost of holiday lighting can increase significantly. If you opt for C7 bulbs, it takes about 100 to decorate a 7-foot tree. The most enthusiastic holiday decorators typically light up their roofs, yards, driveways, and trees facing the street, in addition to indoor Christmas lights and decorations. Even if you plan on a far more modest display, you may want to consider switching to LEDs. Here's a price comparison that illustrates how much you can save with LEDs:

To calculate electricity usage during the holiday season or year-round, find your latest utility bill and use the following formula:

Interesting Christmas light facts

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  1. Energy Saving
  2. Electric
  3. Winter