What Do Christmas Lights Cost to Run?
Outdoor Christmas lights cost very little to run with LED. A 10-metre string light with 100 LEDs uses around 7 watts. Running it six hours a day for the whole season costs roughly half a euro. The same string in old incandescent bulbs would have cost around 35 euros.
The formula
Three numbers give you the answer: the wattage of the product, the hours you run it, and what you pay per kilowatt-hour.
Cost = watts × hours ÷ 1000 × price per kWh
The wattage is printed on the product and listed in the technical details on each product page. Divide by 1000 because electricity is priced per kilowatt-hour, and a kilowatt is a thousand watts.
A worked example
Say you run a 10-metre string light at 7 watts, six hours a day, from the first Sunday of Advent until Twelfth Night. That is about 40 days, so 240 hours.
7 × 240 ÷ 1000 = 1,7 kWh
At 30 cents per kWh, that is 51 cents for the whole season.
What a full display costs
Typical figures over a 240-hour season at 30 cents per kWh:
- String light, 10 m, 100 LEDs (7 W): about 0,50 €
- Net light, 3 × 2 m, 432 LEDs (25 W): about 1,80 €
- Large LED motif (48 W): about 3,50 €
- Six products together (about 150 W): about 11 €
A decorated house with lights on the facade, a motif in the garden and net lights on the hedge lands somewhere between 10 and 20 euros for the season.
Why LED changed the maths
An incandescent Christmas bulb draws around 5 watts. A hundred of them is 500 watts, which over the same 240 hours is 120 kWh, or about 36 euros for one string.
The LED equivalent is 7 watts. That is roughly 70 times less for the same length of light.
This is why people can now light the whole house rather than one window. The limit is no longer the electricity bill.
Max watt and actual watt
The figure on the product is the maximum the product can draw. Actual use is usually lower, because few products run at full output all the time.
Max watt matters for a different reason: it tells you how many products you can connect together. Our LED motifs can be chained up to a total of 130 watts on one power cord. Add up the max watt of each product and keep the total under that.
How to cut the cost further
- Use a timer. Six hours in the evening rather than all night halves the running time.
- Run them when they are seen. Between 16:00 and 22:00 covers the hours people are actually out.
- Check the IP rating, not the price. Lights that fail after one season cost far more than the electricity ever will.
Frequently asked questions
How do I find the wattage of a product?
It is in the technical details on the product page and printed on the power cord or the product itself.
Does leaving lights on standby use power?
A plugged-in transformer draws a small amount even when the lights are off. It is a fraction of a watt, so over a season it is negligible, but unplugging after Christmas does no harm.
Is it cheaper to run fewer, bigger lights?
Not necessarily. Watts are watts. A single large motif at 48 W costs more to run than seven string lights at 7 W each.
What is a normal electricity price?
Household prices across northern Europe have sat between 20 and 40 cents per kWh in recent years. Use your own rate from your bill for an accurate figure.
