From variance to value: Stabilizing circular exchanges in industrial symbiosis networks

1st year PhD student Enar Leferink recently published a new paper titled ‘From variance to value: Stabilizing circular exchanges in industrial symbiosis networks’ in the Journal of Industrial ecology. Here is what he had to say about it!

“This article emerged from the realization that, although practitioners and academics frequently noted that waste is a challenging input to manage in a tight operation, very little research had actually examined the issue. The challenge has an obvious parallel in variable renewable energy sources such as wind and solar. When I met Ebbe Vestergaard in 2023—then Head of Research at the GreenLab eco-industrial park—it became clear this was a substantial unsolved problem. GreenLab already had byproduct exchanges complicated by fluctuations in quantity and quality, and planned to integrate renewable energy from a nearby wind and solar plant, adding yet another layer of variability across the cluster.

Two issues became particularly clear. First, it is often unknown how byproduct flows behave inside circular industrial systems—how they relate to firms’ internal operations, and how fluctuations in one place tend to create fluctuations elsewhere. To address this, we created Variance Flow Analysis, which builds on flow visualisation principles and mirrors mass- or energy-conservation ideas to reveal how variance originates, spreads, or is absorbed, helping firms prepare for and maximize the value of byproducts.

Second, companies often struggle to see the economic benefits of using another firm’s byproducts because they fear supply disruptions. For this, we developed the Variable Byproduct Technoeconomic Investment Model (VBTIM), a stochastic optimisation tool that identifies the optimal combination of variable byproduct infrastructure and stable conventional input infrastructure, balancing cost, risk, and environmental benefit.

Applied to GreenLab Skive, these methods show when firms can rely more heavily on variable byproduct streams and when additional backup or storage is needed. The work aligns well with Refficiency’s focus on designing circular industrial systems that are low-carbon, operationally reliable, and economically sound.”

To read the full paper click the button below.