Permanently green traffic lights for sustainable properties

Dreamer or visionary?

Callebaut once said that he dreamt of a city resting on three pillars.^[3] The first pillar: a decentralized energy supply. This can already be implemented today, as demonstrated by “plus energy buildings” – i.e. buildings that do not need any energy but generate it themselves. According to Callebaut, this energy could be diverted into neighbouring buildings. The second pillar: urban farming, the combination of building and cultivation, the next stage of vegetable patches on balconies. Pillar three: short routes, with no need for cars. This also means that a property should serve quite different purposes. Not living “here” and working “there”, but working and living at a single location – with shopping facilities only 50 metres away. This means that cars can be used far less frequently, cutting down on CO₂. Callebaut believes: “We must rediscover the spirit that villages had in the past.”^[3]

Vision meets reality

In fact, many of his ideas has already found its way to reality by now. Take the Agora Gardens high-rise designed by Callebaut in Taipei, for instance, on top of which some 23,000 trees and shrubs grow.^[4] There is also space for tenants’ own organic gardens. Callebaut, the Belgian sustainability visionary, certainly never seems to run out of ideas.

An example of this is Paris. Notre Dame Cathedral, damaged by fire, is to be unceremoniously adorned with a glass roof along with a rooftop garden – at least if Callebaut gets his way. The garden is planned to yield up to 21 tonnes of fruit and vegetables per annum.^[5] And Callebaut has also proposed revamping France’s capital completely in architectural terms. In 2015 he presented a concept in this regard: by the year 2050, Callebaut wants to organically integrate a number of sustainable buildings, such as anti-smog and pro-photosynthesis high-rise towers, into the classical cityscape of Paris. The idea behind this is to purify the air and supply the surrounding buildings with energy and air-conditioning.^[6] And what is planned to be inside the buildings? A colourful mix of apartments, hotels and offices.

Sustainable building is worthwhile

The ecology-minded building trend has already been around for some time. Take home ownership, for instance: most German home owners insist on sustainable construction.^[7] On a small scale, this means well-insulated windows or water-saving bathroom or kitchen fittings. And on a grand scale? Are we talking about high-rises or complete, urban districts designed by Callebaut? Why? The global population is growing, with more and more people expected to be living in cities in future – unleashing a dramatic burden on the environment.^[8] The topic of sustainability thus has permanently green traffic lights worldwide. In Hamburg, for instance, the Senate endorses rooftop greening and is now thinking of increased facade greening in order to improve micro-climatic conditions.^[9] In Abu Dhabi, a complete, sustainable Masdar City is to be produced “out of thin air” in the desert sands by 2025.^[10]

Sustainability no longer is simply a matter of personal convictions, but also a question of entrepreneurial calculus. This was shown in a survey taken among real estate investors.^[11] 93 per cent of respondents declare their intention to take account of sustainability criteria in making their investment decisions. One of the reasons for this is that stricter legislative requirements are likely to be imposed. Sustainable buildings that easily meet the relevant requirements are thus considered to be more future-proof than conventional buildings.^[12] For this reason, in the case of DWS real estate funds, for a long time now the sustainability of properties has been subjected to just as close scrutiny as conventional key figures and ratios.^[13] Investors can therefore benefit comfortably from a global trend. Without having to watch Japanese animation movies like “Tenkū no Shiro Rapyuta”‚.