It’s that time of year again: Christmas lights will soon adorn almost every lamppost, tree, and shop window in sight. But has it ever crossed your mind just how much energy goes into powering these dazzling displays?
Research shows that Christmas lights add £79 million to the nation’s energy bills, highlighting that lighting up our homes for the festive period can be detrimental to both our wallets and the environment.
Conscious of this impact, the energy comparison experts at Uswitch sought to compare the luminous output of a city at night during Christmas time compared to a regular month. Through analysing night time satellite data from NASA, Uswitch can reveal which European cities use the most energy to light up for Christmas.
Top 10 cities that use the most energy for Christmas lighting
1. Milan, Italy
The European city that uses the most energy for Christmas lighting is Milan. The fashionable north Italian city sparkles 69.25% more during December than pre-festive month October.
Milan’s streets are lit up for the advent season, with festivities continuing well into January. But December isn’t just about Christmas—it’s also a time to celebrate the city’s patron saint, Sant’Ambrogio. Between 5-7 of December, the streets of Milan play host to the festival—which perhaps contributes to the higher light energy expenditure during this month.
2. Istanbul, Turkey
Turkey’s largest city, Istanbul, is filled with Christmas lights and celebrations in December. Along with a few festivities, residents build a celebratory atmosphere leading up to the new year during this time.
Perhaps this is why Turkey’s largest city sees a whopping 69.14% increase in nighttime light output in December. Even though Christmas isn’t as big a celebration as it might be in the rest of Europe, you’ll find the streets and restaurants of Istanbul adorned with festive lights and decorations during the advent season.
3. Ljubljana, Slovenia
Slovenia’s capital city generates a hefty 67.57% brighter nights in December compared to October, and it’s not hard to see why. December is a vibrant month in Ljubljana, with unique and abstract Christmas lights decorating the city’s streets in an artful display.
Designed by artist Zmago Modic, Ljubljana’s Christmas lights are part of an ever-developing project that exhibits some unusual and awe-inspiring sights, such as galaxies and geometric shapes.
4. Stockholm, Sweden
Famous for its glögg and gingerbread offerings, Christmas in Stockholm lights up the city 49.33% more than non-festive months.
Sweden’s capital city switches on the Christmas spirit from mid-November, when over 40 streets and squares around the city centre are illuminated by some one million LED lights, many exaggerated with festive touches, such as angels and mistletoe.
5. Oslo, Norway
The Christmas spirit brightens the city of Oslo by an impressive 48.53% more than other non-festive nights of the year.
You’ll find Norway’s capital adorned with twinkling Christmas lights, brimming with Christmas markets and filled with festive celebrations throughout December. St Lucia’s Day is recognised on 13 December, while 23 December is known as Lille Julaften (“Little Christmas Eve”) when any final decorations are hung—including Christmas tree lights.
6. Frankfurt, Germany
Germany’s financial hub, scattered with towering skyscrapers, is also the home of the annual Christmas Garden Frankfurt. The German city lights up the Deutsche Bank Park between mid-November and early January, boosting its light energy output by 42.37%.
Luminous festivities continue at the Frankfurt Christmas Market—one of the oldest German Christmas festivals, dating back to the late 1300s—and is a spectacle not to be missed.
7. Dublin, Ireland
Christmas lights in Dublin are switched on as early as six weeks before Christmas Day, perhaps adding to the boost in light energy expenditure of 41.76% between October and December.
In 2021, an estimated one million low-energy LED light bulbs lit up the Irish capital, with Grafton Street hosting over 300,000 lights alone. The vibrant display adds to the Christmas charm of the Irish capital city in December.
8. Amsterdam, Netherlands
Despite the city council’s recent plans to reduce the size and output of festive lighting, Amsterdam still generates 40.73% more light energy in December than in October.
Not only are the streets of the Dutch capital illuminated by festive twinkles, but new technologies have also allowed residents to buy outdoor Christmas lights for a lower cost than before—with domestic decorations perhaps adding to Amsterdam’s December light energy output.
9. Athens, Greece
Greece’s historical capital, Athens, throws out an extra 33.65% light energy during the festive season, despite Christmas not being as big an event as it is in other European countries. In fact, at 108.01 nano-watts of light (see table above for details), Athens actually generates the most light energy in December out of all the top 10 European cities.
Come December, visitors can find Christmas lights scattered around Athens, from Syntagma Square in the heart of the city to the quirky and seasonally themed cafe, Little Kook.
10. Andorra la Vella, Andorra
Independent co-principality Andorra la Vella sneaks into the top 10 cities with a 32.52% increase in illumination in December. Interestingly, the city outputs the least amount of light energy in both October (6.04) and December (8.01) compared to all other cities in the top 10.
A popular Christmas ski destination, Andorra’s capital city’s floodlit night skiing opportunities may contribute to its light energy output in December, along with the sparkling Christmas Village that fills the streets with light and colour from late November.
Top 10 cities that use the least energy for Christmas lighting
1. Luxembourg City, Luxembourg
Luxembourg City proved to be the most energy-efficient European location, where luminescent output actually decreased by 9.58% from October to December.
Despite hosting an annual Winterlights festival between mid-November and the beginning of January, Luxembourg appears to be less lit in the festive season than in October. A drop in fairground operators, fewer chalets and a general reduction in festivities could have brought the numbers down.
2. Hamburg, Germany
A major city that saves energy during December is Hamburg. Despite illuminating the entire area between the Elbe and the Alster lake with colourful lights for the festive season, Hamburg’s light energy use decreases by 4.54% from October to December.
Despite being located 800km north of Bavarian capital, Munich, where Oktoberfest is held, Hamburg likes to host events to celebrate the world-famous festival. The Oktoberfest marquees, parties and restaurants are likely to create a boost in light energy in October, more, perhaps, than the Christmas celebrations of December.
3. Bratislava, Slovakia
Even with the Christmas markets and illuminated outdoor ice skating held at Hviezdoslav’s Square, the capital of Slovakia uses slightly less (-1.15%) light energy in December compared to October.
Popular events and festivals, such as the Bratislava Music Festival and jazz performances, held in October may boost the city’s light energy output, as well as only a modest amount of Christmas lights hung around the city could bring balance between the two months.
4. Vienna, Austria
Austria’s “City of Music” demonstrates a mere 2.04% increase in light energy output in December compared to October. From the Long Night of Museums to the GAME CITY festival, there are many nighttime events throughout October that could contribute to elevating nighttime lights in Vienna outside of Christmas time.
With the benefit of energy-efficient LED lighting, Vienna’s tasteful Christmas light displays illuminate the city without too much impact on its energy bills.
5. Chișinău, Moldova
Moldova’s capital, Chișinău, uses the least amount of light energy out of this top 10. The city sees just a 4.25% light increase between October and December, despite hosting festive celebrations in the last month of the year.
Interestingly, Chișinău celebrates Christmas on 25 December and 7 January, due to following both the Julian and Gregorian calendars—perhaps sharing some of the light energy expenditure across the two months.
6. London, England
From sparkling Southbank to the famous Oxford Street Christmas Lights, visiting the UK’s capital to see the city lit up is a festive tradition for many. But despite London’s widespread illuminations, the city only expends 5.09% more light energy in December than in October.
Perhaps the late-night livelihood, exhibitions and general year-round festivities contribute to high light energy use in London outside of the festive month, minimising the difference between Christmas time and the rest of the year.
7. Helsinki, Finland
Finland’s sustainable capital brightens by only 5.55% more in December than in October. With just six hours of daylight in December and reliable snowfalls in the winter months, it’s unsurprising that Helsinki’s nighttime light output shows only a small difference.
Cheery Christmas lights are located in Helsinki’s main street, Aleksanterinkatu, with ‘Little Christmas’ (pikkujoulu) celebrations and parties taking place in the city’s bars and restaurants.
8. Copenhagen, Denmark
Embodying the concept of hygge (the Danish concept of creating cosiness and enjoying the good things in life), Christmas in Copenhagen couldn’t be merrier.
Despite featuring incredible Christmas light displays, including the twinkling lights of Tivoli park, Copenhagen’s light energy output in December is only 5.75% higher than in October. Head to the canal on 13 December for an extra twinkling treat, when hundreds of kayaks are adorned with Christmas lights to celebrate Saint Lucy’s Day.
9. Zagreb, Croatia
Croatia’s famous capital becomes a winter wonderland come advent, with Christmas sparkle brightening its medieval centre. A surprising destination for Christmas markets (move over Germany), Zagreb starts its festive celebrations in late November.
With a fairly high light energy output in October, Zagreb’s light energy increases by only 6.21% come December. Perhaps if October was instead compared to the city’s annual Festival of Lights held in March, the difference may be greater.
10. Paris, France
Just keeping within the top 10 cities that use the least energy for Christmas lighting is Paris. The City of Love brightens by only 7.54% more for advent compared to the less festive month of October.
Festivities are held all over the French capital. Trees are draped in twinkling lights, Boulevard Hausmann is lined with sparkling lights and the streets of Champs Elysées are lit up with amazing Christmas light displays.
How to save money on energy and have a more sustainable Christmas
If you’re planning on decking out your home with twinkling lights but are worried about the impact this will have on the environment or your energy bills come the new year, here are some money-saving tips just for you.
Learn to read your energy meter to predict your Christmas energy bill
It's important to be able to read your electricity meter and gas meter to make sure your bills are accurate, especially when it comes to adding Christmas lights, cooking and general festivities to your expenses.
Understanding smart meter readings is equally important for identifying and reducing energy bill costs.
Switch to a green energy supplier for a more sustainable Christmas
Green energy—also known as renewable energy—is generated from natural and renewable sources that don’t run out or harm the environment. Green energy packages also tend to be cheaper than traditional tariffs that use harmful fossil fuels.
Sarah Broomfield, energy expert at Uswitch.com, comments:
"Your Christmas light display size and choice of bulbs, whether incandescent or LED, could have a significant impact on your energy bill.LED Christmas lights consume 80-90% less energy than incandescent bulbs, so choosing these should affect your energy bill the least over the festive period.
We've compiled three top tips for saving on your energy bills this Christmas:
1. Save money by turning lights off during the day when they don't have much impact, before bed and when leaving the home. You can also opt to buy lights that have a timer, which will allow you to set a schedule.
2. Ensure you choose low energy lighting, such as LED bulbs. They tend to cost more money, but they use less electricity and last longer over time.
3. Compare the energy rating of the lights you're planning on purchasing before you buy. This will let you know whether they have a low or high energy consumption, which will inform the impact on your energy bills."
Methodology
Methodology
Uswitch.com/gas-electricity/ sought to determine which European cities had the greatest increase in brightness during the month of December based on outdoor night-time artificial lights.
Utilising satellite data from NASA’s Black Marble night-time lights dataset (VNP46A2), the increase in outdoor illumination of 46 cities across Europe was extracted.
This study focuses on analysing the Gap-Filled Lunar BRDF-Adjusted Night-time Lights dataset that measures nocturnal visible and near-infrared (NIR) light in watts per square cm per steradian. The data is captured by the Day-Night Band (DNB) sensor of The Visible Infrared Imaging Radiometer Suite (VIIRS) of the Suomi National Polar-Orbiting Partnership (Suomi NPP) spacecraft.
Europe’s daily Night-Time Lights (NTL) data was collected for the months of October 2020 and December 2020 and the dataset was subsequently corrected with NASA’s Black Marble algorithm that accounts for cloud cover, snow Bidirectional Reflectance Distribution (BRD) effect, lunar reflectance, and atmospheric effects.
Subsequently, Natural Earth’s Populated Dataset was used to reverse-geocode the night-time lights to capital cities. A 10km radius around each city coordinate was used to define the spatial range of the city.
For the purpose of this study, only main cities were included as part of the data. Exceptions were also made to municipalities (e.g. Andorra) which were also included.
The sample was then aggregated by each European city to calculate the daily average night-time lights.
Results from Vaduz, Sofia, Riga, and Vilnius were excluded from the study due to abnormally high readings that can be attributed to alternative sources of energy usage.
Following that, the final percent change of city brightness was determined from the median of the night-time lights for October and December.
The final percent changes were then ranked in descending order to discover the European city with the most increase in brightness during December.
Data was accessed between 04/11/2021 and 11/11/2021 and is subject to change.
