2 Low Energy Certificate - for Buildings The energy rating of buildings in different climate-regions of the world will be made according to a system of stars, where the number of stars is proportional to the quality level of a building, comparable to the hospitality industries rating system. At this a summarising rating is provided consisting of: a. Thermal insulation level in winter. b. Heat protection in summer. Certification - Standard of Buildings 1 * Standard very poor upgrades obligatory for Energy consumption in Winter and/or Summer 2 * * Standard poor upgrades necessary for Energy consumption in Winter and/or Summer 3 * * * Standard good upgrades preferable for Energy consumption in Winter and/or Summer 4 * * * * Standard very good Standard according Building standard in Europe 2007 5 * * * * * Standard excellent Standard according Low Energy Buildings in Europe 2007 3 Character of the Certification Procedure Object Energy Efficiency Certificate for Buildings - only envelope Parameters Effective Energy Demand Qp A buildings energy demand, which is necessary to maintain the specific thermal indoor-conditions (heating, heating and cooling, cooling). It is a pure constructive and physical parameter without consideration of any technical equipment. Creteria qh – normalised heating demand of the building qfc - normalised cooling demand of the building qx real building ≤ qx comparison building Boundary Conditions - exterior climate (reference climate for different regions) - position (azimuth / surface normal) - use - construction - thermal balance model with reasonable simplifications 3.1 Annual Heating Demand The balance of thermal losses and gains is calculated for the heating period. 3.2 Annual Cooling Demand The evaluation/certifying of the summer behaviour of buildings is done by a simple procedure for energy-conscious planning of buildings. Here criteria for a "cooling-energy neutral" facade are set up. Experiences show that building facades can be optimized regarding window size and glazing characteristics in connexion with sun- and glare-shield mechanisms in such a way that the building (without further internal heat loads) does not overheat, while the daylight lighting of the rooms is not limited. This means, that buildings with "cooling-energy neutral" facades should not overheat in idle-state. Characteristic values and characteristics of a "cooling-energy neutral" facade are determined by model calculations at a reference building by means of a dynamic climate simulation with the calculation software TRNSYS.