Decarbonisation of the Basque Country residential stock by a holistic enviro-economic assessment of renovation strategies under the life cycle thinking for climate risk mitigation

The present study introduces a novel methodological decarbonisation evaluation for the Basque Country (northern Spain) residential building stock with a bottom-up approach. The investigation relies on the need to develop detailed roadmaps towards decarbonising the residential stock, as demanded by the European Union (EU). Besides, the residential stock decarbonisation evaluation presents several challenges, such as the effective integration of the life cycle thinking (LCT), the diversity of building typologies, the performance gap caused by occupant behaviour and economic uncertainty. The research is based on evaluating renovation strategies in multiple residential scenarios by a complete level buildings performance simulation (BPS) and the enviro-economic evaluation with LCT. For that, we employ the tool PARARENOVATE-LCT. As a result, the bottom-up approach identifies optimal renovation scenarios for each building typology. Secondly, we set different decarbonisation scenarios, where most archetypes require active renovation strategies to reach a deep decarbonisation degree. Thirdly, we develop phased decarbonisation plans by prioritizing archetypes with the highest decarbonisation potential. This way, the plans allow a linear reduction of global warming potential (GWP) with a limited renovation rate and investment in the first stages with an increasing trend, enabling the adaptation of industry and administration.