Guide: How much electricity do fairy lights use?

Published 2025.09.24

But how much electricity do they actually use? In this guide, we break it all down. We’ll look at how much power different types of fairy lights consume and share some smart tips on how to save energy – and money – without giving up on that cosy lighting. 

Power consumption depends on the type of fairy lights 

The amount of electricity fairy lights use depends on the type you choose. Traditional incandescent bulbs, once the go-to option, use significantly more energy than modern alternatives. LED lights, on the other hand, are known for their energy efficiency and long lifespan, making them a popular choice. You’ll also find solar-powered fairy lights that harness energy from the sun, helping you cut down on electricity use even more. 

For indoor use, you might also come across fairy lights with small halogen bulbs, which use more energy than LEDs. The type of fairy lights you choose doesn’t just affect the mood and look of your home or garden, but it also impacts your yearly electricity bill and environmental footprint. That’s why it’s worth considering both the style and the energy use before making your choice. 

Indoor vs outdoor fairy lights: What’s the difference in energy use? 

The energy consumption of indoor and outdoor fairy lights can vary quite a bit. Outdoor chains are usually built to handle the elements, which often means they’re bigger, sturdier and use more power. Indoor fairy lights, on the other hand, are typically lighter, smaller and designed for controlled environments, so they tend to use less energy. The type of bulb also matters: LED lights are far more efficient than traditional incandescent ones, whether used indoors or out. 

Choose LED fairy lights with peace of mind 

Worried about rising energy costs and thinking twice about putting up fairy lights this Christmas? No need to skip the festive cheer. Even with higher electricity prices, you can still create a cosy holiday atmosphere without the bill going through the roof. Choosing LED fairy lights could be the solution you’re looking for. 

These modern fairy lights are a great alternative to traditional ones, as they use significantly less energy. Not only are LED fairy lights better for the environment, they also let you enjoy your Christmas lights indoors and out without worrying about high running costs. 

A traditional fairy lights with 100 incandescent bulbs can cost up to 9.60 DKK per day to run, adding up to nearly 300 DKK if used non-stop throughout December. In comparison, LED fairy lights used 24/7 might cost anywhere from just 0.04 to 3.60 DKK per day. That means your December lighting could end up costing between 1.24 and 111.60 DKK depending on the type and number of chains you use. The difference is clear especially if you’re decorating with several fairy lights. Some LED chains are so efficient they use as little as 1 watt, meaning the energy use is barely noticeable. 

How much electricity do fairy lights use? 

If you want to calculate the exact energy use of your fairy lights, there’s a simple formula you can follow. Let’s say you have fairy lights that use 7.4 watts and are switched on for 8 hours a day throughout December. To convert watts to kilowatt-hours (kWh) which is what your electricity bill is based on, divide the wattage by 1,000. Then multiply that by the number of hours the fairy lights are on per day, and again by the number of days it's used. This gives you the total electricity consumption for the month. 

Keep in mind that prices per kWh can vary from supplier to supplier and depending on the contract you have. If you want to know your exact kWh price, you need to contact your supplier.

If your energy plan includes variable hourly pricing, you might be able to save money by using electricity during off-peak hours when demand (and prices) are lower. Since electricity prices change throughout the day, it’s a good idea to monitor current rates. There are websites and apps available to help with this, so you can plan your usage for the cheapest times of day. 

In the illustration below, we’ve shown a sample calculation based on the average 2025 electricity price in Denmark. (Keep in mind that energy prices fluctuate, so this is just a snapshot based on current rates.) 

That's how little it costs to light a string of lights from Biltema

The price is based on DKK 2.36 per kWh. (September 2025):

• Type: LED light chain with 100 LED bulbs
• Consumption per hour: 7.4 watts = 0.0074 kWh per hour
• Consumption at 8 hours: 0.0074 kW x 8 hours = 0.0592 kWh
• Price for 8 hours of use: DKK 2.36 x 0.0592 kWh = DKK 0.1397.

For an LED light chain with 100 bulbs that is lit 8 hours a day, it costs: DKK 0.98 per week

Top tips for saving energy 

Decorating your home or garden with fairy lights is a great way to create a warm, cosy vibe but it can also impact your energy bill. Luckily, there are a few easy ways to keep the mood without the extra cost. 

One of the simplest tips is to use one of our timers. By connecting your fairy lights to an automatic on/off function, you’re in full control of when they’re switched on. That way, they’re not using energy around the clock. This is especially useful in winter when you want the lights to turn on in the early evening and off again late at night. If you're using a timer for outdoor Christmas decorations, make sure it's approved for outdoor use. 

Another handy tip is to check the wattage before buying new fairy lights. Lower-wattage options use less power  which is good news for both the planet and your wallet. LED lights are usually the most energy-efficient choice. They use only a fraction of the power compared to traditional bulbs and last much longer too. 

You could also think about switching to solar-powered fairy lights. These are ideal for outdoor use, charging up during the day and glowing in the evening without drawing on your household electricity. By following these simple tips, you can enjoy all the festive sparkle without worrying about your energy bill. 

Shop your fairy lights at Biltema 

At Biltema, you'll find a wide range of fairy lights for both indoor and outdoor use. Perfect for creating a warm and inviting atmosphere in any space. Our indoor fairy lights come in various lengths and shades, from warm white to cool white, ideal for setting a festive mood at Christmas or adding a special touch to your next celebration. 

Our outdoor fairy lights are built to withstand the weather and bring a cosy glow to gardens, balconies and patios. Wrap them around railings, drape them along fences or hang them from the roof edge to light up your home’s exterior. In our outdoor selection, you'll also find beautiful icicle-style fairy lights for decorating the house, and light nets – perfect for draping over bushes or trees. Whatever the occasion, Biltema’s fairy lights make it easy to set the right mood, indoors or out. 

Need more lighting? 

Looking to brighten up your home beyond just fairy lights? At Biltema, we’ve got you covered with much more than festive lighting. For indoor use, we offer a range of modern recessed spotlights which are ideal for focused lighting in any room. Or check out our smart, flexible LED strips. These are perfect for adding ambient light under kitchen cabinets, along staircases or behind TV screens. We also stock tube light fixtures for offices, institutions or kitchens, giving you long-lasting and efficient lighting solutions. 

If you’re lighting up your outdoor space, Biltema has a great selection of outdoor lamps and solar garden lights for patios or gardens. These products are built to withstand the elements and provide reliable, effective lighting for paths, entrances and other outdoor areas. Our solar lights are especially popular for their easy installation and sustainable energy use and therefore a great choice for eco-conscious households. At Biltema, you’ll find lighting that combines quality, function and style so it’s easy to find the perfect solution for any space.