The facility’s walls, roof, and foundation are super tight and highly insulated. The triple-glazed windows help save energy, and they also stay much warmer, which reduces condensation. The building can tolerate much higher humidity levels as a result, which lowers ventilation costs. The ventilation system is based on an energy recovery ventilator or ERV, which extracts the energy in the moist air with incoming fresh air – a mainstay of Passivhaus design. The hot, sauna ventilated air is captured to help heat other parts of the building.
Energy comes from a combined heat and electrical plant or CHP, which runs at around 70% efficiency – double the energy efficiency of a separate boiler and electrical generator. The unit also runs on biogas, and exhaust heat is cycled through a condensing boiler to heat the pool water. A large Photovoltaic system on the roof produces a peak 110 kWs of electricity.
Photos © Ruhrn Achrichten