The mining and metals industry faces an increasing demand for product carbon footprint (PCF) and life cycle assessment (LCA) information requested by customers, investors, and legislators. In parallel, the number of standards and guidelines according to which these PCF and LCA studies shall be conducted is continuously growing. In response to this increasingly demanding and complex reporting landscape, the International Council on Mining and Metals (ICMM) took initiative to develop methodological recommendations for a harmonized calculation of metal PCF/LCA results, which is presented in this paper. A criteria-based comparison of 16 PCF/LCA standards and expert interviews were conducted to identify their requirements regarding relevant methodological aspects such as system boundaries, the modelling of electricity, or allocation. Based on this, proposals to harmonize the way of modelling within the mining and metals industry have been developed and discussed with ICMM and its member associations and companies. Besides internal consistency, compliance with guidelines of relevant industry initiatives and upcoming legislation was aimed for and checked in a consistency analysis. A comparison matrix has been developed which maps the requirements of 16 PCF and LCA standards concerning 17 methodological aspects. The level of consistency among different metal PCF guidelines ranges from high (e.g. functional until and system boundaries), medium (e.g. cut-off criteria and modelling of electricity), to low (e.g. multi-output allocation) – with some aspects being addressed by very few guidelines only (e.g. offsetting and recycling allocation). The consensus finding process resulted in recommendations for all 17 methodological aspects to enable a consistent way of conducing PCF and LCA studies of metals. While specifying the generic requirements of international standards for the mining and metals industry, some flexibility is needed to acknowledge the complexity and diversity of metal production routes, which are better addressed in metal-specific guidelines. As methodological requirements are often similar, more specific, or stricter than those of other standards, PCF/LCA studies conducted in line with the recommendations provided in this article will largely fulfil the requirements of other international standards and guidelines developed by other industry initiatives. Aiming to harmonize the calculation of life cycle-based environmental information of metals, recommendations for key methodological aspects in PCF and LCA have been developed, which allow for a large degree of consistency with international standards and guidelines from industry initiatives.
Markus Berger (Sun,) studied this question.