Jets back and forward between Singapore (photo) and Switzerland: star architect Kees Christiaanse. Photo: iStock

What is a smart home?
A house that can perform certain tasks and operations itself. If it recognizes the person approaching the house, it automatically opens the front door. Depending on the signature of the person in question, the electronics can go on to perform certain processes inside the house. At present, there are countless ways in which a building can be fitted out. But technologies are subject to constant change. I almost find architecture and urban design more important.

In the past, there was a tendency to believe it would no longer be possible to use old buildings efficiently in the future. Then we went in search of solutions. Thanks to their solidity, old walls really have a lot of storage space. They are slower to cool down in winter and faster to heat up in summer. Now, old houses can be heated using heat pumps instead of coal. And some apartments have been converted into lofts. When construction, change and new usage are not synchronous, a place develops more naturally.

What does that mean?
The capacity for resistance is greater than when changes take place too quickly. In Switzerland, plots of land and properties tend to be small. This offers additional protection against a too-fast pace of change. When land is all too readily available, such as in the Dutch polders, this can lead to the creation of monofunctional suburban areas that are lacking in quality.

How do you live?
I live near the Rigiblick funicular in Zurich, from where I can walk down to the railway station or up into the woods. I could even reach the airport within 30 minutes by bike. I don’t need a car. Short distances lead to sustainable lifestyles.

No car, but you do fly?
I would also like to see sustainable mobility by air. People are unlikely to want to travel less. Being able to trade, interact, move in the globally networked economy is part of what makes us who we are, part of our success.

At least you travel to far-away cities to study sustainability there.
Of course, it’s paradoxical that working on sustainable economizing involves a lot of flying around. However, airplanes produce far fewer emissions than the building stock.

For all those who travel less than you do: Where have you seen the future?
There are likely to be different futures. Europe’s greatest quality is that some 500 compact, medium-sized cities can be found within an area of 1,000 square kilometers. In between, there is a flourishing cultural landscape that is relatively intact, diverse and ecological. Most places are accessible by public transport. That’s a fantastic model! In South-East Asia, the average distance to the urban centers is five times as high and there are five to ten times as many inhabitants. Buildings are growing both vertically and horizontally. Because public transport links between towns are underdeveloped and have to cross difficult topographies, flying is even more important there.

What kind of high-flown technology have you encountered?
The way in which the window panes on Singapore’s MRT trains change seems pretty crazy to me. When travelling through high-density residential areas, they turn milky. Once back among the trees, they become transparent again. Experiments with hydroponic facades and rooftops, where plants grow on vertical frames, strike me as very interesting. They are watered by the rain and computer-controlled systems. The layers of vegetation provide protection from the sun, store water and produce food. When the water evaporates, they help cool the building down.

Can we eat these plants?
Many people believe that “urban farming” could make a significant contribution to feeding the population. Only salad greens, spices and some fruits can actually be grown on buildings. But it’s nice to see that these systems, like the heat generated by computers, household appliances and residents, can also serve as complementary energy sources. A well-insulated building hardly needs any external power nowadays. But cooling is likely to become more important than heating.

Where do you see additional potential?

The key challenge at present is to be ‘smart’ at city and district level. We have already seen district heating being produced by municipal waste plants. There is boundless potential for linking energy and waste disposal flows. An unused office building could supply the power left over in the evening to a neighboring residential building. Given the right infrastructure, the optimum circulation of energy can be achieved. For whatever it is then needed for.

What is the smartest technology in your home?
We have nothing, we’re completely analog; we don’t even have a TV or a burglar alarm.

ETH professor Kees Christiaanse is an advocate for slow urban change.

Simply smart

A house is ‘smart’ when it meets real needs such as energy efficiency and security. Functions should be as user-friendly as possible. Something as simple as an app module can create fantastic light scenarios or monitor rooms. To keep unwanted guests away: program light and music differently. As a rule, do not buy any spy devices. However, ‘being smart’ goes far beyond your own four walls. Kees Christiaanse, Professor of Architecture and Urban Design, sees a great deal of potential in the “linking together of energy and waste disposal flows”. Just thinking about it is the first step towards achieving this interaction.