Effects of promoting decarbonization and digitalization on future copper cycles in Japan

• We projected future copper cycles in Japan by stock-driven approach complemented by bottom-up approach. • Copper demand in 2050 will be nearly equivalent to 2015 levels. • Copper demand driven by decarbonization and digitalization will account for 17 % of total demand by 2050. • Lithium-ion batteries in battery electric vehicles will be the main source of future waste copper. The promotion of decarbonization and digitalization is expected to increase global copper demand. Meanwhile, metal use levels will not infinitely increase with economic growth, and the populations of some developed countries have begun to decline, resulting in conflicting drivers of future copper demand. This study revealed the effects of increasing decarbonization and digitalization technologies on future copper cycles in Japan through high-resolution dynamic material flow analysis of 249 final products, combined with input-output analysis. The copper demand associated with conventional end uses is projected to decline, while that driven by decarbonization and digitalization is expected to increase significantly, leading to a total copper demand in 2050 nearly equivalent to that in 2015. Decarbonization and digitalization technologies are expected to become major contributors to waste copper flow, accounting for approximately 10.8 % of the total waste flow by 2050. Notably, waste lithium-ion batteries from battery electric vehicles are projected to become the largest source of copper recovery among all final products during 2040–2050.