In recent years, initiatives have been launched internationally aimed at increasing the number of sustainable cities and municipalities. But what does the phrase “sustainable city” actually mean? It should be said that different definitions have been applied at different times. As part of Agenda 2030, and so one of the sustainable development objectives established by the UN, point 11 states the aim of “making cities inclusive, safe, resilient and sustainable”, where the last word, from a certain point of view, summarises the words that precede it.
So let’s see why it is so important to talk about a sustainable city and how to make a city effectively sustainable.
Sustainable cities and municipalities: why they are a priority
The 193 member nations of the General Assembly of the UN included the point about sustainable cities and municipalities in Agenda 2030 based on a simple analysis of the reality in which we live: the global urban population has grown considerably in the last century and will continue to do so in the coming decades. It will therefore be vital to design sustainable cities.
The numbers show how much population distribution has changed in the modern era. Only 13% of humanity lived in cities in 1900. Fifty years later, that percentage had reached 29% and touched 50% in 2005. By 2030, on current estimates, the urban population will make up 60% of the total. Leaving aside the percentages and looking at the demographic statistics from those days, the urban population stood at 220 million in 1900 while, in 2005, it was 3.2 billion; in 2030, it will probably be 4.9 billion people.
In North America, 82% of people live in cities, with a slightly lower percentage in South America (80%). In Europe, the urban population is 74% of the total, slightly higher than Australia and Oceania; in North Africa it is 52%, in Asia 48% and in Southern Africa 38%. Faced with this urbanisation, launching projects for sustainable cities is crucial.
The meaning of sustainable city
As mentioned, various definitions of sustainable city have been given over time. To understand the meaning given to this phrase at the institutional level, it may be useful to look at the criteria adopted by one of the most important studies dedicated to sustainable cities and municipalities, that is, the Arcadis Sustainable City Index.
This identifies the three pillars of sustainable cities: social performance, environmental/energy factors and financial health. As can be surmised, sustainability in this case should be understood in the broadest and more general way: a city is sustainable when the people who live there can grow socially and economically in a healthy way and with respect for the environment.
The pillar regarding social performance used in the Arcadis Sustainable City Index specifically – but not exclusively – refers to people’s quality of life; it considers factors such as life expectancy, the crime rate, the level of obesity, the cost of living and so on.
The second group of factors is more closely linked to urban planning, with a sustainable city that must pay particular attention to questions connected to the environment and energy. The focus is therefore on pollution, the use of clean, renewable energy, waste management, water quality and so on.
Finally, there is the third pillar, linked to the financial situation of companies and people: including factors that must be considered such as the simplicity of launching new businesses and the health of companies.
Examples of sustainable cities
Many rankings have been drawn up by various bodies listing the most sustainable cities in Europe and at the international level. London topped the last edition of the aforementioned Arcadis Sustainable City Index, for example, followed by Stockholm, Edinburgh, Singapore and Vienna.
As regards Italy, reference can be made to the data and ranking drawn up by the EY Smart City Index, which analyses all 109 major cities in Italy every year. Top of the ranking in the 2020 report was the city of Trento, followed by Turin and Bologna. Trento, specifically, benefited from excellent results in terms of energy, the environment and transport, while Milan – in fifth place – was prominent, for example, for the quality of its mobility sharing services.
How to make a city sustainable
The city of the future must therefore be sustainable. But what are the factors that actually need to be worked on to effectively make the various municipalities sustainable?
To design a sustainable city, a whole series of aspects must be taken into consideration. Major investments are required in the energy field in order to constantly increase the share of energy produced from renewable sources, as well as upgrading buildings from the energy efficiency point of view.
Another fundamental question, inextricably linked both to the protection of the environment and energy management, concerns urban transport. In a sustainable city, in fact, a high-quality public transport system must be provided in order to speed up and simplify travel and make urban mobility less polluting, in any event incentivising citizens not to use their own cars but favour buses, the metro, car sharing, bike sharing, bicycles and other green, smart vehicles.
Next, of course, comes differentiated waste collection, as well as urban green spaces, a concept that in recent years has resulted not only into parks being cared for but also in the creation of urban gardens and green roofs. In a sustainable city, zero land use must be established, relying on the modernisation of existing buildings instead of concreting over additional areas.
Wi-Fi throughout the country, the internet of things and home automation will be the elements that make up all the sustainable cities of the future in order to reduce energy waste, make the city safer and, for example, encourage smart working, which in turn will lead to a reduction in pollution.
And these are only some of the many factors that must be taken into consideration to design a sustainable city.