A global impact assessment framework for long-term decarbonisation of vehicle electrification and energy policies

Abstract

Electric private Vehicles (EVs) are one of the primary solutions to combating climate change in the transportation sector. However, countries’ fossil-based Electricity Generation Mix (EGM) has undermined the decarbonisation effort of EVs. As prior studies have analysed either cities or countries in isolation, this study proposes a new assessment framework to explore the trend of carbon emissions from Private Vehicles (PVs) under EGM reform and EV popularisation from 2012 to 2050 with a multi-scale analysis and comparison (country-scale, province-scale, and city-scale). The framework was first applied to understand the effectiveness of the EV popularisation in Mainland China. The results reveal that a significant spatial variability is found among the Chinese provinces, with a country total reduction of 2,301 kt CO₂e/year in 2035. The eastern provinces have substantially higher CO₂e emissions than the central and northern provinces, despite the central provinces having a higher carbon intensity in EGM. The vehicle population dominates the trend of province-based total emissions. In Mainland China, the aggressive popularisation of EVs with continued coal reliance for electricity generation has jeopardised the effort of carbon emission reduction. To further evaluate the patterns and trends of the effectiveness of EV popularisation from a global perspective, selected countries/cities, including Hong Kong, Singapore, Vermont, Oslo, and Luxembourg which have pledged to retire fossil-based vehicles, and India, Australia and Japan from literature, were adopted in the analysis. Overall, the status of per-vehicle emission ranking in 2035 is Oslo < Japan < Singapore < Luxembourg < Hong Kong < India < Australia < Vermont < Mainland China, with the lowest and highest values of 153 and 2289 CO₂e kg per PV, respectively. These five selected countries/cities are expecting to achieve significantly higher overall emission reductions (> 42% in 2035, >60% in 2050) than China (~ 15% in 2035), with Vermont having the greatest reduction from its aggressive carbon-free EGM reform and the 100% substitution of fossil-based vehicles with EVs.

Keywords

Electricity generation / Carbon emission reduction / Electric vehicles / Sustainable transport policy / Energy and climate change

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Funding

Departmental Research Support Fund, HKU

RIGHTS & PERMISSIONS

The Author(s)