Primary energy implications of different design strategies for an apartment building

In this study, we explored the effects of different design strategies on final and primary energy use for production and operation of a newly constructed apartment building. We analysed alternatives of the building “As built” as well as to energy efficiency levels of the Swedish building code and passive house criteria. Our approach is based on achieving improved versions of the building alternatives from combination of design strategies giving the lowest space heating and cooling demand and primary energy use, respectively. We found that the combination of design strategies resulting in the improved building alternatives varies depending on the approach. The improved building alternatives gave up to 19-34% reduction in operation primary energy use compared to the initial alternatives. The share of production primary energy use of the improved building alternatives was 39-54% of the total primary energy use for production, space heating, space cooling and ventilation over 50-year lifespan, compared to 31-42% for the initial alternatives. This study emphasises the importance of incorporating appropriate design strategies to reduce primary energy use for building operation and suggests that combining such strategies with careful choice of building frame materials could result in significant primary energy savings in the built environment.