Comprehensive renovation of a multi-apartment building in Sweden: techno-economic analysis with respect to different economic scenarios

Abstract

ABSTRACT A wider deployment of nearly zero energy buildings (NZEBs) is expected to contribute to the transition to a decarbonized and energy-efficient building sector in Europe. This study proposed an integrated energy-economic analysis to exemplify the feasibility of NZEB renovation in temperate climate. A parametric analysis was performed to identify technical building system configurations that give minimum share of renewable energy systems contributing to NZEB level. Final energy savings, global costs and cost-effectiveness of renovating a building to NZEB level are analysed, considering active and passive energy efficiency measures (EEMs). The active EEMs included efficient water taps and heat recovery ventilation, and the passive EEMs encompassed insulations to roof, exterior walls and ground floor, and improvements of windows and doors. The building had initial final energy use of 133 kWh/m2 year for space heating, domestic hot water production (DHW) and facility electricity. The results show that NZEB level is achieved with active and passive EEMs, without renewable energy systems for scenarios with low discount rates and high future energy price escalations. The annual final energy use for space heating, DHW and facility electricity is reduced cost-effectively by 37-54%. Furthermore, increasing size of PV-system enhanced cost-effectiveness by lowering total global costs.