Assessing the relevance of energy indicators as sustainability screening metrics for the decarbonisation of industrial heat through electrification

Power generation faces the challenge of reducing its greenhouse gas emissions without shifting the burden to other environmental impacts. Energy and exergy-based environmental indicators have proven to some extent to be effective environmental proxies for the current energy mix but the robustness of this approach has barely been discussed in the frame of energy transition scenarios. Hence, the aim of this study is to analyse their relevance in the context of decarbonisation of industrial heat through electrification. To this end, we investigate the potential relationships between two different energy indicators and environmental indicators using life cycle assessment (Ecoinvent database, 16 environmental indicators, 2 energy indicators) for 28 pairs of energy sources shifting for the production of 1 kWh of electricity. For the reference French case, no similar trends across all sources of energy, for given environmental and energy indicators are found neither between all environmental and energy indicators. The extension to other cases is discussed, leading to the same conclusion. These results highlight the need for a multi-criteria assessment to evaluate the impacts of industrial heat in a context of intensive process electrification, which will be country dependent because of the various strategies in achieving net-zero electricity mix.