Every week, 1.5 million people move to towns and cities, putting huge demands on local resources and environments. Yet with the right techniques and technologies, urbanisation and sustainability can go hand-in-hand.
The megacities of the future
For the world’s growing population, the future is urban. It’s estimated that by 2030 there will be 41 “megacities” with more than 10 million inhabitants1. Today there are just 182. The people in these cities will consume 81 percent of the world’s resources3. Twenty years later, by 2050, these urban populations will need 50 percent more food and 17 percent more water than they do today4. They will want to live comfortably, too. There are still 1.2 billion people without electricity today: tomorrow’s urban dwellers will want modern housing and energy, with a pleasant indoor climate.
This shift to cities comes at a cost. By 2050, current projections suggest that population growth and urbanisation will generate a two- to three-fold rise in global energy use for the building sector, with a similar impact on associated emissions5. When global environmental targets demand major reductions in energy use and CO2 emissions, it’s hard to see how this urbanised world can be sustainable.