I'm about to buy a car, an electric one. It's a big thing for us, because we didn't own one, we didn't need one for almost nine years. But I've been talking about cars and transport a lot already.

Today it's about the pure geometry of living and its influence on our emissions. Let's talk about housing.

First, there's the geometry of a building with a simple fact that smaller structures have comparably more surface area and the surface area is the place where heat gets out in winter and in in the summer. A zero emission house is either passive by itself (what we call zero energy house) or uses sustainable energy from the outside (passive house).

But the smaller it is, the more tech needs to go into the surface, the more it costs and the more problematic the room climate is getting.

Therefore bigger blocks are by far the most efficient way to live in terms of environment. However we reach a tipping point somewhere where comfort is suffering, e.g. where there are flats that don't receive natural light anymore.

Additionally, big housing projects usually need quite some infrastructure. Parking lots, roads, density of public transport, which comes with a high ratio of sealed surfaces - cement gardens.

We have to hit the sweet spot there and new housing projects probably lie in the middle. Densely populated, but still with a lot of green.

Last aspect today is another geometric argument. The closer people live together, the closer the grocery stores, pubs, fitness studios can be. And therefore many things will be in walking distance range. You will not achieve that in rural areas.