Comparing projections of industrial energy demand and greenhouse gas emissions in long-term energy models
The industry sector consumes more energy and emits more greenhouse gas (GHG) emissions than any other end-use sector. Integrated assessment models (IAMs) and energy system models have been widely used to evaluate climate policy at a global level, and include a representation of industrial energy use. In this study, the projected industrial energy use and accompanying GHG emissions, as well as the model structure of multiple long-term energy models are compared. The models show varying degrees to which energy consumption is decoupled from GDP growth in the future. In all models, the sector remains mostly (>50%) reliant on fossil energy through 2100 in a reference scenario (i.e., absent emissions mitigation policies), though there is significant divergence in the projected ability to switch to alternative fuels to mitigate GHG emissions. Among the set analyzed here, the more technologically detailed models tend to have less capacity for switching from fossil fuels to electricity. This highlights the importance of understanding of economy-wide mitigation responses and costs as an area for future improvement. Analyzing industry subsector material and energy use details can improve the ability to interpret results, and provide insight in feasibility of how emissions reduction can be achieved.