Unseen machines: illuminating equipment’s role in climate change mitigation and resource efficiency

Empirical research from a top-down perspective employing input-output analysis suggests that we use one third of the metals to produce machinery and equipment and that their production causes 8% of global greenhouse gas emissions. Yet, our empirical understanding of how much different types of machinery and equipment contribute is limited. Machines are not represented explicitly in climate change mitigation models. There is limited research on mitigation opportunities related to machinery and equipment, and the practice and potential for circular material flows has yet to be explored. It is a very diverse category. For an overview, economic statistics and input-output models building on these are essential. Mitigation opportunities, however, can only be understood through engineering research of specific types. We identify several data sources available for empirical research and indicate options to combine these. We present a dozen propositions for further research. A machinery and equipment scenario model would represent cohorts of machinery archetype parameterized based on empirical parameters derived from statistical data, as well as application- and machine-specific engineering models. It could help us understand investment dynamics, future metal demand, and mitigation opportunities.