Energieffektivisering i flerbostadshusområde från 1950-talet : Åtgärder med fokus på minskad energianvändning för uppvärmning av tappvarmvatten

Sammanfattning: The aim of this study was to investigate energy saving measures, primary for reducing the energy use for heating domestic hot water in Gamla Studentstaden, Uppsala. Gamla Studentstaden, a residential area for university students built in the 1950’s, consists of 14 buildings with student dormitories and apartments. Furthermore, the study aimed to present an overall cost analysis of the measures. The investigated measures were; drain water, individual metering and charging of water, solar thermal collectors with and without seasonal storage and exhaust air heat pumps combined with solar cells. Theoretical formulas showed that drain water and individual metering and charging of water decreased the demand of delivered energy by 0.6-2.4% and 0.2-2.5% respectively. According to the cost analysis, drain water was a profitable measure. Individual metering and charging of water was however not due to complicated installations. Using VIP Energy as a simulation tool, the remaining measures were investigated. With solar thermal collectors, the demand of delivered energy decreased by 3.8-5.8%. Combining solar thermal collectors with seasonal storage, the energy reduction increased to 4.3-7.1%. Implementation of exhaust air heat pumps reduced the demand of delivered energy by 37.6%. Combining exhausted air heat pumps with solar cells led to a reduction of delivered energy of 39.6%. Neither thermal solar collectors nor exhaust air heat pumps were profitable measures. However, solar cells as a sub-system in combination with exhaust air heat pumps were considered profitable.