These four numbers define the importance of our cities: 2, 50, 75 and 80

Cities are home to more than half the world's population, and that number continues to grow. How should they adapt to cope with demand? This is a question that will increasingly be answered by technology, says Carlo Ratti, Director of MIT's Senseable City Laboratory and co-chair of the Global Future Council on Cities and Urbanization. In this interview, Ratti envisions a future where our homes, offices and even our furniture is designed to evolve and respond to how we use them, rather than the other way around.

Four numbers define the importance of cities: 2, 50, 75 and 80. Cities occupy 2% of the world’s surface, but they are host up to 50% of the world’s population, are responsible for 75% of global energy consumption and 80% of CO2 emissions. Hence, if we made our cities just a little more efficient, we could have a major global impact.

The internet is entering the physical space, merging the physical and digital layers – and this is opening up a new world of applications, from energy to mobility, water management to citizen participation.

For example: today, a staggering amount of energy is wasted on heating or cooling empty offices, homes and partially occupied buildings. At MIT we researched how the Internet of Things could help to synchronize human presence with climate control – that is, heating or cooling people, not entire buildings. We developed and tested prototypes that we are now applying architecturally – for example, in the redesign of Fondazione Agnelli, an historical building in Torino, Italy.

Occupants of the building will be followed as they move around by a personalized heating, cooling and lighting system, like an individually-tailored environmental bubble, optimizing space usage and limiting energy waste.

Think about our working lives. We already have the technological tools to enable remote working, but most of us still commute to offices every day. Why hasn’t remote working taken off as much as many people thought it would? Because being in the same building makes it easier for people to share knowledge, generate ideas, and pool talents and perspectives.

But how do we maximize these effects? That’s a question technology will increasingly answer. New tools are emerging to measure human connections and spatial behaviour and how they relate to productivity and creativity. That will inform how workplaces are organized.

Historically, buildings have been rigid and uncompromising – more like corsets than t-shirts. Increasingly we will design buildings and digitally integrated furniture that evolve and respond to how people use them, rather than requiring humans to adapt to them.

I think that what will change most radically by 2030 will be our way of living in cities: how we work, move, buy, meet, mate, and so on.

Consider mobility: cars are becoming computers on wheels, capable of driving themselves; data analytics is enabling smarter real-time management of traffic; and, with the rise of the sharing economy, people are increasingly thinking of cars as something they don’t need to own. Recently at MIT we studied mobility demand in Singapore, and found that it could be met with 30% of the vehicles currently in circulation.

In theory, this number could be cut by another 40% if passengers traveling similar routes at the same time were willing to share a vehicle. This implies a city in which we could travel on demand with just one-fifth of the number of cars in use today. Among other benefits, that would free up large swaths of parking areas for other uses.

There are roles for governments, the private sector, and citizens alike. For example, the reductions in car numbers I just envisaged are only theoretical – they depend on people’s willingness to share rides, and to adopt self-driving technology. We can easily also imagine a nightmare scenario, in which cars become cheaper, more and more people buy them instead of using mass transport, and cities become even more congested by 2030.

Like the beginning of the internet, today’s beginning of the Internet of Things will require a lot of trial and error. The safety and security of the systems we are building is one crucial factor – we are all familiar with viruses crashing our computers, but what if the same virus crashes our cars? We will need innovators and regulators to work closely together, with regulation closely following technical progress and fixing the problems that will surely emerge.