Energy use and CO2 emission of new residential buildings built under specific requirements - The case of Växjö municipality, Sweden

The Växjö municipality sets specific energy related requirements beyond the Swedish building code (BBR) when selling land for the construction of new residential buildings. The requirement for Östra Lugnet residential area was that all buildings must be connected to the local district heating network and installation of heat pumps was prohibited in developer-built group/row houses. This paper (a) analyzed if the energy use of the buildings fulfilled the requirements of the BBR and that of Växjö municipality, and (b) compared the primary energy use and CO2 emission from operation of the district heated buildings with hypothetical scenarios where only air-source or bedrock heat pumps were installed. Results showed that a significant proportion of the group/row houses did not fulfil the specific energy use requirements of the BBR and that of Växjö municipality. There were large variations between predicted and actual energy use. Using a marginal accounting approach, houses with district heating were found to have the lowest carbon emission. From this perspective it seems appropriate for Växjö municipality to set the requirement that new residential buildings in Östra Lugnet be connected to the local district heating network.