Challenges and opportunities for carbon neutrality in China’s building sector—Modelling and data

The building sector is one of the largest energy user and carbon emitter globally.To achieve China’s national carbon target,the building sector in China needs to achieve carbon peaking and neutrality targets by 2030 and 2060,respectively.However,data deficiency on building energy and emissions become barriers for tracking the status of building energy and emissions,and identify potential opportunities for achieving dual carbon targets.To address these shortcomings,this study established an integrated China Building Energy and Emission Model(CBEEM).With CBEEM,this study evaluated the building-construction and building-operation energy and emissions in China,and revealed the status quo and potential challenge and opportunities.According to modelling results,building operation energy use of China was 1.06 billion tce in 2020,accounting for 21%of China’s total primary energy consumption.Building construction energy consumption was 0.52 billion tce in 2020,accounting for another 10%of total primary energy consumption.Key messages found on building carbon emissions are:building construction embodied emissions were 1.5 billion tCO_(2) in 2020 and are declining slowly,building operational carbon emissions were 2.2 billion tCO_(2) in 2020 and are still increasing.International comparisons between China and other countries on building stock,energy use intensity and carbon emission intensity were conducted as well,and help shed a light on the challenges for decarbonization of China’s building sector.Finally,technology perspectives to achieve carbon neutrality target were discussed and related policy suggestions were provided.

Decarbonization path of China’s public building sector from bottom to top

The building sector is one of the three major energy consumption areas and one of the main areas responsible for carbon emissions.In 2019,carbon emissions related to construction and building operations in China accounted for 38% of the total social carbon emissions,of which construction accounted for 16% and operations accounted for 22%.Due to its large volume and high energy consumption per unit area,public buildings account for 38% of the operating energy consumption of all buildings,that is,8% of the total national energy consumption.At this time,the building industry must take decarbonization actions to avoid a delay in realizing carbon neutrality and an emission peak.We need to form a unified process for the implementation boundary,implementation path,and index system to build a zero-carbon implementation plan for China’s public building sector.Based on bottom-up practical cases,this paper proposes the KAYA model,which is applicable to different scales and different types of public buildings/communities,and proposes specific and feasible plans.Through the implementation of demand reduction,energy efficiency improvement,and the fully-use of renewable energy in all five clear steps,this paper promotes the implementation of decarbonization in China’s building industry.

Technical pathways of dual carbon control in China’s buildings sector

Reducing carbon emissions in the buildings sector is of great significance to the realization of China’s carbon peak and neutrality goals.By analyzing factors influencing buildings carbon emissions at the operational stage,this paper applies the China Building Carbon Emission Model(CBCEM)to make medium and long-term forecasts of China’s building operation carbon emissions,discussing the goals and realization paths of China’s dual carbon goals in the buildings sector.The results show that building operation carbon emissions,according to the current development model in the buildings sector,will peak in 2038-2040 with a peak carbon emission of about 3.15 billion tons of CO_(2);however,by 2060,carbon emissions will still be 2.72 billion tons of CO_(2),falling short of China’s dual carbon goals.The carbon saving effects of three scenarios,namely clean grid priority,building photovoltaic priority and energy efficiency enhancement priority,were measured and shown to be significant in all three scenarios,but the building photovoltaic priority and energy efficiency enhancement priority scenarios were superior in comparison.