(NEXSTAR) — Believe it or not, the holiday season is again upon us. Whether you’re wrapping your tree in a simple strand of lights or adorning your home in enough lights to make Clark Griswold jealous, the type of bulbs you select could have a big impact on your electric bill.
A recent survey found that on average, Americans will spend about $384 on outdoor holiday light decorations. That does not, however, include the cost of the electricity used to light them.
Before you purchase your lights, there’s a relatively easy way to figure out how much your electric bill will go up due to your light display.
First, you’ll want to find the wattage of the strand of lights. This is usually printed on the box or listed on the specifications section if you’re buying online. Then, follow this formula:
- Multiply the wattage by the hours per day the lights will be on, then divide by 1,000 to find kilowatt hours, or kWh per day
- Multiply the kWh per day by your cost of power usage (found on your electric bill) to find the cost per day
- Multiply the cost per day by how many days your lights will be on
The latest data from the U.S. Energy Information Administration shows the national average price for electricity for customers in September 2023 was about 16.29 cents per kilowatt-hour (0.10 more than last year at the same time). That rate varies, with those in Alaska, California, Hawaii, and New England seeing higher-than-average costs.
Now, the comparison.
Three different styles of light strands — mini, C9, and C7 — are compared below, based on whether the bulbs are LED or incandescent. For these comparisons, each cost was based on six hours of usage per day, over 30 days.
A strand of 300 white mini LED lights on the typical green wire is 21 watts, while the same style with incandescent bulbs is 72 watts. Using the formula above with the national average of 16.29 cents per kilowatt-hour and a display season of six hours a day for a month, using a strand of mini LED lights will cost you about 62 cents. A strand with the same amount of incandescent bulbs will cost about $2.11.
If you’re looking at a strand of 100-light C9 LED lights at 4.8 watts, it will cost you about 14 cents, while a 25-light strand of C9 incandescent lights at 175 watts costs about $5.13. For the 25-light LED C7 strand at 21 watts, your cost is about 62 cents, while the incandescents at 125 watts will cost about $3.67.
It’s also important to remember this is just one strand of lights. To figure out just how much your display will cost, make sure to multiple the total you found above by the number of strands you used.
Of course, the total cost is dependent on the local cost of electricity.
For those in Hawaii, where the average electric cost is 41.52 cents per kilowatt-hour, the range expands to 36 cents to $9.34. Residents in Washington are the best off: with a kilowatt-hour rate of 11.38 cents, the above lights would cost between 10 cents and $3.60.
In Illinois, for example, the average price for a residential customer was 14.79 cents per kilowatt-hour (that’s down about 2 cents from last year). At that rate, the above costs would range from about 12 cents to $4.66.
While LED light strands tend to cost more at the store — those referenced above range from about $32 to $80 compared to the incandescent strands ranging between $13 and $28 — incandescent will put a greater strain on your electric bill over time.
So how much would Clark Griswold’s iconic light display from the 1989 film “National Lampoon’s Christmas Vacation” cost today?
Since the film was set in Chicago, we’ll use the above data for Illinois. Let’s say he used this set of white incandescent string lights. He’d need 1,000 strands in order to have 25,000 individual bulbs (not imported from Italy). Using the formula above, that light display would cost him about $186.30 after a month. With this similar set of LED lights, he’d need 250 strands of lights, which would cost him about $31.93.
Neither option would help make the outlet look less overwhelming, though.