Detailed modelling of basic industry and material flows in a national energy system optimization model

National energy system models are often ill-equipped to examine the interconnections between material and energy systems, and the tradeoffs between energy or material use of limited resources are left unaddressed. An adapted energy system model (IESA-Opt) combined with a revised dataset, including 22 new material flows, 33 new processes, and revisions to existing processes, broadens the range of solutions. We show that including additional detail in the major energy-intensive material production sectors has a significant impact on the results of a net-zero emissions scenario for the Netherlands. The result is different optimal technology investment pathways compared to the previous scenario, and total system costs that are 0.8 % lower over the time horizon. The results highlight the value of explicitly including detail on energy-intensive material and industry in analyzing interactions between sectors – particularly waste, chemicals and fuel production – and points to improvements in energy system modelling for industry.