EPBD i praktiken: Konflikten mellan energiprestanda och klimatpåverkan i det befintliga fastighetsbeståndet : En fallstudie av ett 1940-talshus

Sammanfattning

The revised energy performance of buildings directive (EPBD) aims to reduce energy usagewithin the building stock in the European Union. In Sweden the energy performance is regulated bythe national building code (BBR) and isindicated with a unit called primary energy number. The Swedish national board of housing, building and planning (Boverket) is working on implementingthe directive into Swedish legislation through stricter energy performance requirements. The primary energy number as a metric th at takes energy consumptionand energy carriers through weighting factors into account. The aim of this master thesisis to investigate the potential goal conflicts that come with EPBDfocusing on energy performance and climate impact. This study is conducted as a case studyof a residential building from the 1940s, where three scenarios are analyzed. The first scenariois a reconstructed original configurationof the building that works as a baseline, the secondand third scenarios focus on different heating and ventilation systems. The results show that the renovation strategies yield different outcomes whether energy performance or climate impact is used as the evaluation basis. A strategy focused on district heating combined with h eat recovery ventilation (HRV) improves the primary energy numbersignificantly. While an alternative strategy based on an exhaust air heat pump results in lowerclimate impact but no significant change in energy performance. The study demonstrates that the primary energy number is heavily influenced by the choiceof energy carriers and does not necessarily reflect the renovation strategy with the lowestclimate impact. The conclusion is that the primary energy number as a sole steering parameterrisks a goal conflict between energy efficiency and climate impact. To support effective climaterenovations, additional indicators for climate impactare required alongsidewith energy performance assessment.