Taxonomy, Saving Potentials and Key Performance Indicators for Energy End-Use and Greenhouse Gas Emissions in the Aluminium Industry and Aluminium Casting Foundries

Increasing energy efficiency within the industrial sector is one of the main approachesin order to reduce global greenhouse gas emissions. The production and processing of aluminiumis energy and greenhouse gas intensive. To make well-founded decisions regarding energy effi-ciency and greenhouse gas mitigating investments, it is necessary to have relevant key performanceindicators and information about energy end-use. This paper develops a taxonomy and key perfor-mance indicators for energy end-use and greenhouse gas emissions in the aluminium industry andaluminium casting foundries. This taxonomy is applied to the Swedish aluminium industry andtwo foundries. Potentials for energy saving and greenhouse gas mitigation are estimated regardingstatic facility operation. Electrolysis in primary production is by far the largest energy using andgreenhouse gas emitting process within the Swedish aluminium industry. Notably, almost half of thetotal greenhouse gas emissions from electrolysis comes from process-related emissions, while theother half comes from the use of electricity. In total, about 236 GWh/year (or 9.2% of the total energyuse) and 5588–202,475 tonnes CO2eq/year can be saved in the Swedish aluminium industry and twoaluminium casting foundries. The most important key performance indicators identified for energyend-use and greenhouse gas emissions are MWh/tonne product and tonne CO2-eq/tonne product.The most beneficial option would be to allocate energy use and greenhouse gas emissions to boththe process or machine level and the product level, as this would give a more detailed picture of thecompany’s energy use and greenhouse gas emissions.Funding: Swedish Environmental Protection Agency; Swedish Agency for Marine andWater Management [802-0082-17]Carbonstruc