We live in an age of urbanization. For the past ten years or so, more than half of the world’s population has lived in cities. Moreover, there’s no end in sight for this migration of people to urban areas. On the contrary, the latest UN forecast predicts that 70 percent of the world’s population will be living in cities by 2050. At that point, the world’s total urban population will be almost equal to the earth’s entire population today. Within a mere century, the number of people living in big cities will have grown from one billion to almost six billion. This trend will also lead to the rise of more and more megacities — cities that have more than ten million inhabitants. Whereas there were 28 megacities in 2014, there are expected to be 41 by 2030. Demands on infrastructures are expected to grow accordingly. Smaller cities are also expected to grow considerably. In 2016 there were about 500 cities with more than one million inhabitants; by 2030 there could well be more than 650.
Many cities are already suffering from housing shortages, overstretched infrastructures, and uncertain water and energy supplies. Added to this is the increasing risk of natural disasters resulting from climate change. Emissions from big cities, in particular from the transportation sector, are contributing considerably to this development. According to recent studies, the most effective low-carbon strategy would be to electrify this sector. Some areas are already trending in this direction. However, if the rise in global temperatures is to be kept to less than two degrees Celsius, 90% of all road vehicles would have to be electric by 2060.