o limit global warming to 1.5°C or 2°C, achieving a net-zero or near-zero greenhouse gas emission energy system by midcentury is essential. This ambitious target requires the decarbonization of hard-to-abate sectors, particularly transportation and heavy industry. This study employs an integrated energy-economic-climate assessment model to explore decarbonization pathways aligned with these temperature goals. The results show that by 2050, residual emissions from key industrial sectors – such as chemicals, fertilizers, iron and steel, aluminum, and cement – are projected to range from 30.2% to 82.5% of baseline levels under climate policy scenarios. In transportation, emissions from aviation and shipping are expected to remain between 70.2% and 91.2% of baseline levels. The analysis of decarbonization drivers reveals that demand-side strategies – such as improving energy efficiency and optimizing activity levels – are the main levers for decarbonizing aviation and shipping. On the supply side, technologies such as carbon capture and storage (CCS) are crucial for reducing emissions in heavy industries, whereas electrification is key for decarbonizing aluminum. This study provides actionable insights into the strategies needed to achieve a near-zero or net-zero energy system by mid-century, emphasizing the importance of integrating technological innovation with strong policy support.
