Jämförelse av frånluftsvärmepumpar
In order to reach the environmental targets, set up by the EU, there are many measures taken to make Sweden more energy efficient. In the housing and real estate sector, an installation of an exhaust air heat pump that reuses the heat in the exhaust air in order to lower the amount of acquired energy, is an example of such an action. The recovered energy can then be used for heating of radiators and tap water. This report aims to evaluate and compare three different systems using exhaust air heat pumps regarding COP, degree of coverage and cost savings. This study was delimited to only account for apartment buildings.The theory chapter describes the different conditions and factors that affect a building?s energy balance. Further on the exhaust air heat pump is described with focus on function, limitations and advantages regarding energy savings.The first one is located on Västergatan 21 in Växjö and uses recirculation of the exhaust air to increase the air flow through the heat pump. The second system is installed on Toras väg in Karlskrona. This system uses a mix of exhaust air and outside air. The last system on Södra järnvägsgatan in Växjö only uses the exhaust air in its heat pump.The COP for the different installations was 1,89 for Toras väg (average), 3,14 and 3,47 for Västergatan and 3,80 for S. järnvägsgatan for the respective period. The degree of coverage for the installations was in the interval 56,3 ? 91,0% and the cost savings was between 4 900 SEK to 8 600 SEK per month for the observed period of each building.