Cities are responsible for 75 percent of CO2 emissions, scientists estimate. Ambitious urban development projects in Abu Dhabi, China and the US are now competing for the title of the world's first zero-carbon city.
The city of the future should be a city of short distances, easily reachable on foot or by bike. That doesn't necessarily mean a CO2-emission free city has to be small: every neighbourhood would have its own supply unit with access to public transportation.
Local residents would then decide to leave their cars at home, or - in a best-case scenario - get rid of their cars altogether. The ideal city makes good use of its resources and runs on non-fossil energy sources.
The study "Zero carbon cities - between wishful thinking and reality" published by Karl Peter Schön and André Müller of Germany's Federal Institute for Research on Building, Urban Affairs and Spatial Development (BBSR) takes a look at global best-practice models.
The ecological model city "Masdar City" in Abu Dhabi, the capital of the United Arab Emirates, was founded six years ago. A lot of money and scientific know-how was invested - traffic doesn't interfere with pedestrians, as cars run on a separate platform. The architects of this model city test different kinds of solar panels to see what works best in a desert environment.
A wind tower sucks fresh air in from the very top and brings it down to the streets. Local plants which don't need a lot of water cover the city in green. But Masdar City is far from being complete: The financial crisis has put a damper on the project in the desert. Only a couple of buildings and a research institute have been built so far.
It's a completely different feel in Lingang New City, Shanghai's satellite city, as people have started to move in, says Müller. An artificial lake is the in the city's center - the streets then divert from that lake. Shops and other services are right at hand, as well as parks, walkways, biking paths and extensive bus and streetcar services. The urban planners want to get energy from wind, sun, geothermal heat and seawater.
China's government supports this project as a model for ecological sustainable growth, says Müller. About 800,000 people are expected to live and work in Lingang New City.
Schön estimates that Asian cities will grow by half a billion people until the year 2030 - because of higher birth rates as well as migration from rural areas. The Chinese seaport is supposed to show how such masses can be taken care of in an environmental-friendly way.
Plans versus reality
"But Lingang New City also makes it very clear how a complete new planning can cater to the needs of the economy and the people," Müller said. Some additional levels were added to buildings, but the public transportation schedule was downsized as it still lacks the users. And power is mainly derived from nuclear and coal-fired power plants.
Economic growth as well as attracting businesses and new residents comes first, expanding renewable energy sources second. They also abandoned the initial idea to only allow residents to park their cars on the city's outskirts, because it discouraged the middle class from moving as they consider their car as a symbol for freedom and status.
Civano, on the outskirts of the American major city Tucson in Arizona, doesn't possess wind turbines nor bike tracks. But it does have its own eco-project: houses made of straw and recycled construction materials. The architects drew inspiration from Pueblo tribes' huts. This traditional construction technique works well in a desert-environment as it only needs about half as much energy to cool down the place.
For American standards, the city is quite densely populated. Major cities in the US usually have vast, spread-out suburbs which makes people dependant on cars and causes them to waste a lot of gas to travel back and forth.
But Civano's eco-colony is still the first of its kind. The real estate crisis slowed down housing sales, and a change in management led to cut backs in the creative and ecological quality, the study concludes.
Modernizing already existing cities is a lot harder
But as fascinating as new cities in the making are: it's proven to be even more difficult to rebuild existing metropolis in an environmentally-friendly way, as thousands of people already live in a city that has evolved organically - and not all of them are welcoming the changes. In demographically shrinking Europe, it's all about that kind of modernization anyway, says Schön. Solarpanels and green roofs could change a lot within those cities. But financial aid for property owners and an urban development concept are crucial.
Model projects allow businesses to test new technologies in a day-to-day environment. Residents in Lyon, France can soon rent electric cars in the old industrial waterfront area of Confluence and use smart grids to optimize their power consumption based on the time of day, week or year.
Japanese electronics company Toshiba installed such a smart grid in cooperation with the city government and its citizens, says Müller. Since the operator gains access to sensitive personal consumption data, many people were hesitant at first. In order to make this project work, they had to be slowly familiarized with the new technology.
Author: Matilda Jordanova-Duda/sst
Editor: Jessie Wingard