Energy use in multi-family dwellings : measurements and methods of analysis

Abstract: In 2001, multi-family dwellings were built at nine properties in Västra hamnen, Malmö, Sweden. Several well known Swedish architects were involved in designing the buildings, hence they reflect modern architecture. Prior to the inauguration, the buildings were displayed at the international housing exhibition Bo01. The housing exhibition had an ecological and sustainability focus. Regarding energy use, all buildings were restricted to use no more than 105 kWh/m² annually including space heating, domestic hot water heating, common electricity and household electricity. Different building techniques and technical systems were used at the different properties. A measurement program including hourly measurements of district heating, common electricity and household electricity was set up to monitor the energy use of the buildings. The aim of the research project presented in this licentiate dissertation has been to study the energy use at these properties based on the measurements. Use of district heating, use of domestic hot water heating, assimilation of solar heat gains, use of common electricity and use of household electricity were all studied in detail. Power signatures were used to make corrections regarding differences in the outdoor climate between the different years and to study the energy use during different conditions. Methods were developed and used to study parameters that were not measured directly and to study variations in use during the day and during the year. All properties, except one, used more energy than restricted. The variations in total energy use between the different properties were large. There was a factor of almost three between the lowest and largest use. Solar heat gains were assimilated to different extents at the different properties due to different window areas, orientation of the window areas and the technical systems used. The variations during the year and during the day in use of household electricity and domestic hot water heating was considerable and this should be taken into account when measured energy use during shorter periods are compared and when energy simulations are done. Key values are presented that can be used to critically examine different designs, systems and results from energy calculations.