Monitoring the carbon emissions transition of global building end-use activity

TL;DR

This study presents a comprehensive assessment of global building sector decarbonization over two decades, revealing key factors and quantifying emissions reductions in residential and commercial buildings to inform future net-zero pathways.

Contribution

It introduces a novel bottom-up assessment framework combined with a structural decomposition method to evaluate global building emissions and decarbonization progress.

Findings

Commercial building emissions declined by 1.94% annually since 2000.

Residential building emissions declined by 1.2% annually over two decades.

Total decarbonization achieved was 230.28 and 338.1 Mt CO2 per year for commercial and residential buildings.

Abstract

The building sector is the largest emitter globally and as such is at the forefront of the net-zero emissions pathway. This study is the first to present a bottom-up assessment framework integrated with the decomposing structural decomposition method to evaluate the emission patterns and decarbonization process of global residential building operations and commercial building operation simultaneously over the last two decades. The results reveal that (1) the average carbon intensity of global commercial building operations has maintained an annual decline of 1.94% since 2000, and emission factors and industrial structures were generally the key to decarbonizing commercial building operations; (2) the operational carbon intensity of global residential buildings has maintained an annual decline of 1.2% over the past two decades, and energy intensity and average household size have been key to this decarbonization; and (3) the total decarbonization of commercial building operations and residential buildings worldwide was 230.28 and 338.1 mega-tons of carbon dioxide per yr, respectively, with a decarbonization efficiency of 10.05% and 9.4%. Overall, this study assesses the global historical progress in decarbonizing global building operations and closes the relevant gap, and it helps plan the stepwise carbon neutral pathway of future global buildings by the mid-century.