The Lycée pour Professions de Santé in Ettelbruck, now the largest wooden building in the Grand Duchy, is a pilot project. It is indeed the first Luxembourg public building with positive energy. It is also the first in Luxembourg to aim for a "Minergie-P- ECO" certiﬁcation. In addition to the comfort of the occupants, which reaches its highest level thanks to this certification, it is also the ecological footprint of the building that has been at the centre of attention since the design phase.
In this respect, the use of materials with a low environmental impact such as wood for the construction system, or clay panels for the interior walls, has been favoured. Also noteworthy is the use of an innovative hybrid ventilation system that combines natural and mechanical ventilation. In addition, the entire roof is covered with photovoltaic panels and combined with an inter-seasonal heat storage system, and flat solar collectors with a combined surface area of approximately 350 m2 are vertically integrated to heat the seasonal tank installed in the stairwell.
- thermal collectors on the facade with a seasonal reservoir;
- complete roof coverage with photovoltaic panels;
- optimization of solar gains in winter, while avoiding overheating problems in summer.
- photovoltaic installation of 2,121 m²; 258,000 kWh/a;
- 350 m² of thermal collectors on the facade;
- energy storage tank (91,000 l of water, height 20m);
- 24 kW heat pump;
- hybrid, natural and fan coil ventilation.
Reduction of energy consumption:
- controlled ventilation based on CO2 measurement - efficient cooling of the P.V. wave rooms by external air supply;
- high-performance computer equipment and electrotechnical devices A++++;
- optimized lighting (LED);
- minimization of losses by efficient envelope (30 to 40 cm of thermal insulation).
Primary energy need: 39,30 kWhpe/m2.year
Primary energy need for standard building: 89,80 kWhpe/m2.year
Envelope U-Value: 0,23 W.m-2.K-1
Building Compactness Coefficient : 0,21
Air Tightness Value : 0,90