Cities are home to ever increasing numbers of people. To fight global warming, they need to take a different approach – one inspired by the circular economy
Renewable energy, soft mobility, sustainable buildings... cities have every interest in completely overhauling their approach. Energy is a central issue in redesigning tomorrow’s cities. The construction sector – crucial in building tomorrow’s cities - is one of the most heavily polluting industries.Today 55% of the world’s population live in cities and the number is expected to climb to 68% by 2050. Which raises the central question: how can we reinvent tomorrow’s city and make it pleasant and sustainable for as many people as possible? Urban areas now put the environment under great pressure. A report by the Ellen MacArthur Foundation states that "cities consume 75% of natural resources, produce 50% of waste and are responsible for 60-80% of greenhouse gas emissions".
The Agence de l’Environnement et de la Maîtrise de l’énergie (ADEME) in France however says that the consequences of urban development must be distinguished from the consequences of our linear economic model: extract, produce, throw. And it is indeed this model that is at the root of the problems facing urban areas - not the cities themselves. In fact they have a key role to play in the large-scale implementation of the circular economy.
Renewable energy, soft mobility, sustainable buildings... cities have every interest in completely overhauling their approach. Here are some great ideas that have already been put in place.
Renewable energy in the heart of citiesEnergy is a central issue for tomorrow’s cities. Globally, the energy mix is more than 80% dominated by fossil fuels. Cities must therefore integrate much more green energy into their mix.
For example, in cities that could profit from the wind, installing small wind turbines, on a human scale, is one solution that produces renewable energy. Another idea is to produce heat – and therefore energy - from the waste the city generates. In the north of France, Lille is building a “heat motorway”, which will transport the energy produced from waste incineration and be used to heat the city’s buildings. And as for solar energy, the city of Ota in Japan has equipped its buildings with solar panels.
Promote energy efficiency in citiesBut the production, storage and distribution of energy also has to be more efficient. Over the last few years, “smart grids” have begun emerging: they rely on new technologies to distribute electricity more efficiently. In France in 2012, Issy-les-Moulineaux, in the suburbs of Paris, pioneered the system with the IssyGrid project.
With connected sensors, these smart grids take the needs of consumers into account in real time at different points on the network. It makes it possible to continuously balance supply and demand and optimize the production and storage of energy upstream.
Extend the life span of buildingsEssential in urban development, the construction sector is one of the industries that generates the most waste. According to figures published in 2016 by France’s ADEME, it is responsible for over 70% of the country’s waste. Building tomorrow’s cities is therefore a real challenge for a circular model.
One of the solutions that curbs the consumption of non-renewable resources is to extend the life span of buildings - or even transform them. Degraded buildings that could have been demolished have been upcycled; for example the former Saint-Vincent-de-Paul hospital became Les Grands Voisins, an experimental urban village in the heart of Paris. And an old bunker was made into an urban farm called Zero Carbon Food in London.
Another circular solution is to design materials made from waste that can be recycled indefinitely. The Taiwanese startup Miniwiz transforms industrial and household waste into furniture and design objects.
Soft mobility in the citiesThe transportation sector is the world's second largest emitter of greenhouse gases, after energy. Emissions increase as urban areas spread, often resulting in the use of more cars. One of the solutions is to build so-called compact cities, which encourage walking.
It is also essential to set up circular economy inspired mobility. Ecodesigning vehicles and carpooling are some of the solutions that are being developed.
New mobility consumption patterns are also beginning to emerge. For example, short-term rentals - whether cars, motor scooters, bicycles or even people powered scooters - encourage mobility as a service. Citizens are no longer owners, but users.
The need for concerted action in citiesTo speed up the energy transition and fight global warming effectively, city planning and development must be rethought holistically. According to the think tank The Circle Economy, the authorities must adopt regulations along with tax incentives and circular economy incentives. The European Parliament led the way on 27 March 2018 by approving the ban on single use plastics in all European countries by 2021.
Start-ups, large groups, NGOs, local authorities, citizens... To roll out the circular economy at city level, not only must all the economic players be on board, but they also have to be encouraged to develop synergies.
Main picture : Getty Images