It’s vital to pay attention to how we build cities if we want metropolitan areas that make the planet a better place.

Key features of a sustainable city include new homes and retrofitted existing buildings that are energy efficient, public transport that is a viable and cleaner alternative to cars, and the ability to power itself with local renewable energy sources.

The crux is to create the smallest possible ecological footprint, and to produce the lowest pollution possible so that the city’s overall contribution to climate change will be minimal.

Despite the pressure on cities in terms of population numbers, with people and workplaces located so close to one another it’s possible to save energy for transportation and mass transit systems.

Sustainable development of infrastructure and cities is the growth story of the future

Lord Nick Stern, climate economist

In the developed world, energy used to heat and cool buildings and power devices used within them is the single biggest contributor to cities’ carbon emissions. With 50-70% of existing buildings expected to still be in use in 2050, reducing energy demand by retrofitting will be key. Increased use of technologies such as LED lighting will also enable huge reductions in energy consumption in cities.