Economic Topology Optimization of District Heating Networks using a SIMP-like Multi-Material Penalization Approach

In the presented study, a multi-material 'Solid Isotropic Material with Penalization' (SIMP)-like penalization approach for the economic topology optimization of District Heating Networks is proposed. For District Heating Networks, an important technology for carbon-neutral space heating, the upfront investment is a crucial factor for the rollout of this technology. Today, the pipe routing is usually designed relying on a linearization of the underlying heat transport problem. This study proposes to solve the optimal pipe routing problem as a non-linear topology optimization problem, drawing inspiration from PDE-constrained topology optimization. The optimization problem is formulated around a non-linear heat transport model and minimizes a detailed net present value representation of the heating network cost. A discrete network topology and near-discrete pipe design is achieved by using a pipe penalization strategy. For a realistic test case, the proposed algorithm achieves a discrete network topology and near-discrete pipe design that outperforms simple post-processing steps.