By 2050, some 70% of the world’s population will be concentrated in cities. With population growth, global warming and dwindling resources, cities will have to reinvent themselves and become sustainable. But what exactly do we mean when we talk about a “sustainable city”?
Let’s look back at the definition of sustainable development given by the UN in 1987: “[…] development that meets the needs of the present without compromising the ability of future generations to meet their own needs.” So, it’s a vision of long-term development based on three interdependent pillars: ecological, economic and social. Sustainable development comes in at the point where they intersect.
A so-called “sustainable” city therefore assimilates and adheres to the principles of sustainable development. It also reconciles economic viability, social cohesion and protection of the environment. On the ground, this translates into measures concerning housing, education, employment, access to cultural activities, health, management of resources (energy, water, etc.), transportation, city planning, mobility, etc.
Many cities are beginning their transition with the development of eco-districts where the main principles of eco-friendly city planning exist on a more concentrated scale: construction methods and materials to reduce energy consumption, trip optimization with minimal car use and use of soft transportation, promotion of biodiversity, waste reduction, re-use of rainwater, etc.
It’s easy to get a “sustainable” city mixed up with an “eco-friendly” or “green” city. But the environmental angle is not the only one to consider in a sustainable city project. Not all so-called “sustainable” cities are sustainable in the same way.
Each year, Arcadis publishes its sustainable cities index. And in 2018 London took the top spot. The British capital came out on top on account of a high “grade point average” and, more importantly, high People scores. These covers, for example, personal wellbeing (health, education, crime statistics), working life (discrepancies in income levels, number of hours worked) and city life (access to transportation, digital services). The city also scored high on Profit, which includes criteria as broad as the efficiency of transportation infrastructures, economic performance (GDP per capita, the unemployment rate, tourism, etc.) and the quality of business infrastructures (cellphone signal and broadband connectivity, university-based technology research). London’s Planet score is also decent, falling within the first quartile of the indexed cities, but is not its strongest suit.
From an environmental angle, it comes as no surprise to see cities in northern Europe listed, like Stockholm (no. 1), Copenhagen, Oslo and Frankfurt, Zurich, Vienna and Berlin. Compared to cities that score lower in the Planet category, these countries have a lot of green spaces, better air quality and good waste disposal management. They also often have higher investment in low-emissions transportation, especially bike paths.
In terms of Profit, the top spots go to the financial giants Singapore, London and Hong Kong.
Paris, France’s biggest city, comes in 15th position. Although it ranks well in terms of People scores (third place) and therefore quality of life, it still falls short on Planet scores.
Sustainable cities engage in efforts to reduce their dependency on fossil fuels. Energy saving is a major issue, often with energy neutrality or self-sufficiency as the ultimate goal. In France, 45% of energy is used by buildings for heating, lighting, air conditioning, hot water and appliances. So, this is one of the first sectors where the country will be looking to make savings.
In eco-districts, buildings are designed to provide their own power. This often means renewable energy use (like the installation of solar panels) and insulation to minimize heat loss. This goal of energy economy begins at the design stage. Bioclimatic architecture is designed to create optimal living conditions naturally (temperature, light levels, humidity levels, ventilation) by making use of the site’s environment. For example, it takes account of the building’s height and even its depth, its orientation, the materials used, etc. Not to mention, of course, the adoption of environmentally sound habits like turning off unnecessary lights, using low-wattage bulbs, avoiding leaving appliances on standby, using heating or air conditioning sparingly, etc.
Transportation is a big gas guzzler and a major source of greenhouse gases. It’s also at the heart of the struggle to make energy savings. For the sake of the environment as much as for quality of life, sustainable cities are designed to encourage softer transportation, primarily public transport but also cycling and walking.
The spreading-out of built-up areas due to suburban sprawl calls for a lot of private car use and encroaches on farmland and nature. So the sustainable city is a compact city, and a denser one, so as to favor car-free trips. As well as the large-scale development of bike paths, footpaths and public transportation links (bus, subway, tramway), some neighborhoods have opted to invest in fleets of shared vehicles, most often electric, like in Lombok, an eco-district of the city of Utrecht in the Netherlands.
Big cities are increasingly opting for this kind of shared electromobility by developing numerous self-service transportation options. With “zero emissions” during use* and its ability to take the place of private vehicles carrying between five and 10 people, electric car sharing has already won over a lot of cities like Madrid, which is often held up as an example.
Not very far from the concept of the “sustainable” city, we often find that of the “smart” city. However, the two aren’t quite the same thing. A smart city uses IT to optimize the way it works, the management of its resources, and to cut costs. With a set of sensors, the city collects data that allows it to control and adjust its services, sometimes in real time. This applies, for example, to electricity, water, traffic, waste disposal, and schools and hospitals. A smart city is, in a way, a connected city.
So, the concepts of sustainable cities and smart cities can overlap, with the city’s smart features able to contribute to meeting its sustainability goals.
The notion of the sustainable city sometimes seems a little vague and gets overshadowed by the environmental aspect. Even so, it’s clear that a movement toward the transformation of cities to meet today’s and future challenges really is taking shape.
*Neither atmospheric emissions of CO2 nor pollutants while driving (excluding wear parts)
Copyright : xijian, anouchka