Integrated life-cycle optimisation and supply-side management for building retrofitting

Building retrofitting is a powerful approach to enhance building energy performance. The net-zero ambition urges the need to renovate building energy system in view of the life-cycle optimal, to address climate and environmental challenges. Existing retrofitting and optimisation solutions are generally based upon minimising operational energy or cost. However, although building retrofitting can reduce the energy use at the operating phase, additional materials would result in increased embodied energy. The objective of this paper is to devise a novel building retrofitting approach through the integration of life-cycle optimisation and supply-side management. It is an interactive two-set optimisation approach aimed at minimising overall life-cycle energy consumption through determining the optimal design configuration and operating plan of retrofitting energy devices. The essential retrofitting energy devices include passive retrofitting options (i.e., photovoltaic panel and solar thermal collector) and active retrofitting options (i.e., biomass boiler, ground source heat pump, heat storage, electricity storage, and cogeneration system). A modern 3-floor office building in Manchester, the United Kingdom, is adopted to assess the performance of the proposed refurbishment approach. The real-world situation is represented by historical electricity and gas consumption profiles, current building design information, historical weather profile, as well as life-cycle inventory information. The proposed retrofitting optimisation approach can help decision-makers select the optimal retrofitting solution so as to reduce the overall life-cycle energy consumption of office buildings.