By 2050, three quarters of the world’s population will be living in cities. This will put a lot of pressure on cities, as they will have to expand to accommodate the increase in population. Currently, cities consume 75% of the world’s resources. This will definitely go up. What’s more, cities are responsible for 75% of all green house gas emissions while only occupying 2% of world’s land area.
The concept of a sustainable city was born in the 1980s with the realization that rapid economic growth without concern of its effect on the environment would soon make our cities un-inhabitable. Since then, many cities have made huge strides in efficiently use land, reduce pollution and recycle most of their waste either converting it to energy or other uses.
Basically, a sustainable city is one where ecological, cultural and economic systems work to support a sustainable urban future. Although the term ‘successful city’ is relative, there are some key aspects that generally describe what is expected of a successful city. These include;
Affordable and sustainable housing
A City becomes successful when it is able to plan for and provide adequate housing for its residents. A huge shortfall in affordable housing in a city is evidence of poor planning. With the predicted increase of population in our urban centres, the demand for housing will not cease rather, it will increase. Cities will have to build sustainable and affordable housing where everyone could afford living space for rent or purchase.
Affordable mass transit system
For a city to be considered sustainable or successful, having a working public transport system is important. An efficient transport system offers diverse options for people commuting within the urban centres. Mass transit systems reduce pollution from use of personal vehicles – the fewer vehicles the less the pollution.
Hong Kong, which is considered to have the most effective system in the world, has 90% of all movement within the city through its mass transit system. In Bogotá the city has the TransMilenio a bus rapid transit system that is considered to be one of the world’s best networks. The system blends features of train, tram, subway and bus which serve a city of 7million people.
Renewable sources of energy
Any sustainable city has to focus on renewable energy. Persistent and prominent use of fossil fuels creates pollution. In addition, with more and more people moving into cities, the existing sources of energy become stretched. In Austin, Texas all public buildings including the city’s airport is powered by renewable energy. It is the biggest city in the US to only depend on renewable energy.
New York is looking to use its sewage to power the city. Plans are underway to harness the methane and sludge from the sewage to generate renewable energy. With city dwellers generation 1.3 billion gallons of sewage every day this venture will give more energy to the power needs without affecting the environment.
In 2006, Vienna in Austria built the largest biomass plant in Europe. Biomass is usually animal waste, municipal solid waste and agricultural residues that are fired to produce steam that turns turbines to generate electricity. The plant in Vienna delivers heat for 12,000 and electricity for 48,000 households.
Accessible open spaces
Parks, street trees, squares, and other greenery that make up open spaces are vital for a livable city. Open spaces improve the quality of air, absorb carbon dioxide in the air and create an environment where people connect with nature for recreation, meditation and education. Sustainable cities should grow at a sustainable speed and use resources in a sustainable manner. MBA