Cradle-to-grave lifecycle carbon footprint analysis and frontier decarbonization pathways of district buildings in subtropical Guangzhou, China

Abstract

This study conducted a holistic lifecycle carbon footprint analysis of small-scale district buildings in Guangzhou. Building energy system models were developed in TRNSYS software for quantifications on both embodied and operational carbon emissions. Afterwards, a top-down and bottom-up approach is proposed to systematically explore both passive (flexible adjustment on building services systems) and active strategies (e.g., onsite renewable energy supply) for decarbonization transformation. Research results showed that carbon emissions in production and operation stages account for the largest proportion of the total lifecycle carbon emissions. Moreover, active strategies through distributed renewable systems prioritize others in decarbonization transformation, followed by passive strategies in building services systems. In the subtropical Guangzhou, the Building Integrated Photovoltaics (BIPVs) can reduce the operational carbon emission by 26.5%, 24.4% and 22.5% in the hotel, office, and residential building, respectively. The decreasing magnitude of annual carbon emission is between 21897.4 and 206733.0 kg CO2,e when the integrated rated capacity of wind turbine is between 100 and 500 kW. This research provides a generic approach to estimate lifecycle carbon footprint and gives a clear roadmap on decarbonization pathways of buildings, promoting the sustainability transition towards the dual-carbon era.