Construction of carbon emission evaluation methods and indicators for low-carbon technologies in buildings

Global climate change is an increasingly prominent issue, with the building stock significantly to carbon emissions (CEs). Evaluating the effectiveness of renewal pathways and technologies is essential for carbon reduction in this domain. This study adopts theoretical research, field investigations, simulation analysis, and mathematical calculations, and innovatively integrates whole life-cycle evaluation with inventory methods. The carbon emissions reduction (CER) evaluation boundary of low carbon technologies (LCTs) is defined as the pre- and post-application operational stages and technology application stage. A novel comprehensive CER efficiency (CERE) indicator is established, combining the CER with embodied carbon payback time (ECPT), in addition to recommendations for the selection of evaluation criteria based on diverse building requirements. Simulations and calculations for four commonly used LCTs in Chongqing revealed that CERE provides a more holistic evaluation of CER effectiveness than traditional indicators, and identified a suite of LCTs suitable for Chongqing, encompassing replacement of energy-efficient lamps, roof photovoltaics and air source heat pumps. The findings provide a scientific basis for guiding the application of LCTs, renewal pathways and decarbonization management policy formulation in the building sector.