World Meteorological Organization
The World Meteorological Organisation (WMO) is a United Nations agency. It is a 9-storey building with an additional 5 levels of parking. It was built in Geneva on an ungrateful plot of land. This building is the guardian of the soil, climate, hydrology and meteorology of the planet Earth.
Les points fortsLes prestations principales
Multifunctionality is omnipresent in the energy concept adopted by ERTE. In combination with integral planning, multifunctionality leads to synergies and savings. The most striking example is the dual-flow ventilation system: it combines heating, ventilation, air filtering, cooling and humidification in a single system, as opposed to the two systems used in 99% of the world's administrative buildings.
The ventilation is almost entirely integrated into the building's vertical load-bearing structure, the so-called pillar-rocks, and horizontal load-bearing structure, the reinforced concrete slabs. This has made it possible to eliminate costly false floors and ceilings and to save the equivalent of the cost of a floor, i.e. a saving of ten million francs.
The reinforced concrete slabs were originally planned by the civil engineer to be 20 cm thick, which was sufficient for the statics of the building. ERTE requested and obtained a thickness of 27 cm, which could be used as a space for the integration of underfloor heating and cooling, but in the air, i.e. without any drops of water. But also in the integration of these reinforced concrete slabs, the installation of the computer cabling and power current.
This extremely bold concept had never before been realised on such a large scale in Europe. Another consequence was that the building's very large intrinsic thermal mass was "freed up" and "increased" for the comfort of its 650-800 occupants, while reducing the cooling capacity for air conditioning.
This energy concept is therefore exceptionally sustainable and will live as long as the building itself: 100 years, more...?
The new headquarters of the World Meteorological Organisation is definitely ecologically oriented and energy efficient. The aim was to provide a satisfactory climate and comfort in all seasons. And also to spend a minimum of non-renewable energy and to use as much renewable energy as possible.
Today, ecological technical solutions can be more economical and at least as comfortable as so-called “traditional” alternatives. This was the challenge we faced for the new WMO headquarters in Geneva, completed in 1999. The building is completely glazed on all sides and consumes very little non-renewable energy. And the users do not suffer from heat or cold.
In concrete terms, the mandate given to our engineering office for the HVAC (Heating, Ventilation, Air Conditioning, Electricity) part meant that the new WMO headquarters had to remain fit for purpose and up-to-date for at least twenty years after its commissioning. It had to lend itself to the new forms of work (digital nomadism) which imply ever greater mobility and adaptation, without heavy and costly transformations. On the other hand, its impact on the environment had to remain minimal. Finally, as the headquarters of the guardian of the world’s climate, it was obvious that it should consume a minimum of non-renewable energy without reducing comfort. In short, the aim was to build an international energy beacon that was twenty years ahead of its time.
ERTE kept its promises and today, after more than 20 years of installation, the overall energy concept is still working.
The tests and observations carried out proved the feasibility and robustness of the system on a 100% glazed building, whereas this type of building generally overheats, sometimes even in winter (Winterkühfall) and has to be air-conditioned in the middle of winter on sunny days. It can now be stated that the heating, air conditioning and ventilation system, both natural and mechanical, is working as planned, calculated and simulated with the IGLOU software.
The new WMO headquarters, which is particularly economical and low in energy consumption, was only possible because it is the result of the implementation of understood and adapted formulas and not of the systematic application of ready-made recipes. One of these recipes, which borders on a fashionable phenomenon, would have consisted of active cold/heat ceilings. This is a common and widespread solution, the results of which are guaranteed, but at the price of an additional installation, in this case a separate minimalist ventilation device to provide a minimum of air to the occupants so that they do not “suffocate” in their own CO₂ emissions.
Let’s not fool ourselves: finding new solutions to achieve cheaper, less polluting and more environmentally friendly buildings requires time for thorough and lengthy studies, especially to verify new concepts. Mistakes here can be costly, since in construction, the prototype is often the final building.
A second conclusion concerns the reliability of systems: the safest systems are the so-called “passive” ones, i.e. those with few or no mechanical parts, or those with a simple structure, even if they are newly designed. In other words, the more complex a mechanical system is, the less reliable it is, even if it has been tested for years. The problems encountered are usually of human origin, whether it be inadequate management of the installations, negligence in execution or laxity in adjustment, finishing or maintenance.
Traditional techniques can no longer compete so easily with new concepts, and if they are not yet condemned in the name of environmental protection, this will most probably be the case in the near future. Today, priority can be given to ecological and economic solutions, because these are no longer utopian. They exist, they are there, reliable, sustainable and free of uncalculated risks.
All we have to do is adopt them.