Dense urban cities are known for their high populations, towering buildings, traffic and smog. They often forgo parks and green space in order to fit in more office buildings, condominiums and roadways. This means that cities like Beijing, Shanghai, Oslo and Paris suffer from increased air pollution with large city traffic and no trees to capture the CO2 and other air particles. But researchers have found a new solution: the CityTree.
The Dangers of Air Pollution
The World Health Organization (WHO) refers to air pollution as the invisible killer. It is responsible for 7 million premature deaths per year, which makes it the deadliest single environmental health risk. More than 80% of people living in urban cities are exposed to air quality levels that exceed the safe limit as set by WHO.
One way that areas combat air pollution is by planting new trees. Trees are able to catch and absorb pollutants out of the air with their leaves. However, in urban cities, planting forests full of trees is not always an option given the limited space.
What Is a CityTree?
That’s where the CityTree comes in. For urban areas that don’t have the space or time to plant a forest full of trees, CityTrees are the answer. They have already popped up in Oslo, Paris, Brussels and Hong Kong - all urban areas that suffer from poor air quality.
The CityTree stands four meters tall, three meters wide and 2.2 meters deep. It can be built with or without a bench and includes display space for information on the tree or advertising. The tree has Wi-Fi sensors that are able to measure the local air quality. CityTree requires very little maintenance and upkeep thanks to solar panels which provide electricity and a reservoir that collects rain water that’s pumped into the soil. The tree also has sensors that monitor soil humidity, temperature and water quality.
CityTree was invented by Green City Solutions in Berlin. They claim that the environmental benefit of CityTree is equivalent to 275 real trees. CityTrees can absorb 250 grams of pollutants per day and remove 240 metric tons of CO2 emissions per year.
And that’s because the CityTree isn’t actually a tree - it’s a moss culture. Green City Solutions co-founder, Zhengliang Wu, explains, “Moss cultures have a much larger leaf surface area than any other plant. That means we can capture more pollutants.” The moss is able to remove dust, nitrogen dioxide and ozone gas from the air.
How Did the CityTree Start?
CityTree started in 2006 when co-founders Zhengliang Wu, Denes Honus and Victor Splittgerber met while studying at Dresden University in Germany. Together they ran a workshop that focused on urban design and tackling urban environmental problems.
In 2013, Wu, Honus and Splittgerber met Peter Sanger, a graduate in production management for horticulture, and CityTree began to take life.
The Future of CityTree
The CityTree sounds like the perfect solution to air pollution in urban cities, right? Well, that’s what the team at Green City Solutions thought too, until they ran into some red tape. Wu shared one example, “We were installing them (the CityTrees) in Modena, Italy, and everything was planned and arranged, but now the city is hesitant about the places we can install because of security reasons.”
But the team won’t let bureaucratic issues deter them. So far they have installed 20 CityTrees around the world at a cost of $25,000 per tree. They also have plans to install CityTrees in lower-income countries, such as India, that suffer from high levels of air pollution. Eventually, they hope to use CityTree technology to regulate the type of air and temperature in a city.f