Reduction of Energy Use Or Improvement of Efficiency?
Abstract
The article deals with the concept of “Passivhaus” (PH) in relation to the inside environment and compares PH and the concept of bioclimatic design. Bioclimatic design is an integral part of ecobuilding oriented interventions in the built environment. The main numerically expressed goal of the PH is reduction of heating energy use to less than 15 kWh/m2.year. To reach this goal at least triple glazing is mandatory. This consequentially reduces daylighting illumination level in the building. The basic philosophy of daylighting and the first step in design is that the room is provided with it in the worst case, i.e. maximizing daylighting. In second phase interventions connected with the control of intensity or glare must be taken into the account. Cutting off direct contact with the external environment is viewed as the collateral damage in one-sided energy conservation activities. But the concept of alienating people from the natural environment is according to many studies harmful to health and consequentially to the productivity. The external environment is not by definition hostile to human beings; on the contrary it can have stimulative effects on body and mind. Daylight provides quality lighting, stimulates sense of sight and is important communication mode between the internal and external space. The constant change of light improves concentration and responsiveness. The same holds true for acoustic environment and aural perception and sense of smell. The bioclimatic concept is based on simultaneous adaptation to the external conditions and internal needs and requirements. Closer the building is able to follow these two profiles and the better is the communication between them, the more efficient it is. The adaptive model of the built environment system represents the dynamic structure which performs in real time conditions. Such design and usage philosophy enables optimal exploitation of natural resources and rational adaptation of living patterns. The objective of the above described interventions in the framework of bioclimatic design is healthy living and working environment with the lowest possible energy use and not the lowest energy use based on the physiological minima. In the opinion of World Health Organisation (WHO) it is possible that up to 30% of new and renovated buildings is linked with Sick building syndrome (SBS), most of them with bad quality of inside air. The main causes are transport of air through the systems for heating, cooling and air-conditioning (HVAC), emission of gases from some building materials, volatile organic compounds (VOC), moulds and inappropriate disposal of light industrial chemicals from premises or inappropriate cleaning and filtering of outside air.