The aim of this work is to study the influence of global heat transfer coefficient (Utot en W/m2.K) of the opaque walls (walls and roofs) and of the glazed walls (bays) on the annual consumption of heating, cooling and overall consumption energy. We analyze the number of hours of heating and cooling under operation with partial load and full load. Profiles of indoor temperatures are also given. The work is established on several office buildings defined according to a typology built within the framework of a study on energy savings in air-conditioned office buildings in France. Simulations are carried out according to two types of buildings. The parameters of the first one are totally optimized. The elements concern management of ventilation, lighting, office automation, inertia, HVAC system and distribution network parameters. The second building is taken with high internal gains, i.e non-efficient lighting and plug-in consumptions. The two buildings are compared from both points of view of consumption and comfort. Insulation of the walls is systematically increased, by considering approximate values of 1960 passing by actual values and up to future possible values even if they are technically unachievable. At this stage the only parameters that varies are Utot of opaque and glazed walls. The choice of two indicated types of buildings helps to evaluate the interference of the over-insulation with the other parameters of the building and the system. Simulations are carried out for two climatic regions in France, Trappes (near Paris) and Nice. The first climate is cold in winter and moderate in summer in contrary to the second climate. This choice reflects two extreme configurations of loads: high heating with average cooling demands and high cooling with average heating demands.
Consequences of Increasing Insulation on the Annual Energy Consumption of Air-Conditioned Office Buildings
27th AIVC and 4th Epic Conference "Technologies & sustainable policies for a radical decrease of the energy consumption in buildings", Lyon, France, 20-22 November 2006