A MINLP optimization of the configuration and the design of a district heating network: study case on an existing site

Abstract The aim of this work is to propose a tool to help the design of district heating networks (DHN). The configuration (network layout and production technologies) and the design (mass flow rate, temperature, heat capacity to install and area of the heat exchanger) are optimized simultaneously. The originalities of this mixed integer non-linear programming (MINLP) formulation are to: 1 - avoid any constraint on pipe forcing them to be both supply and return, 2 - permit centralized - decentralized – or individual heat productions, 3 - permit cascade connections between consumers. A study case based on an existing DHN is discussed. First some optimal design parameters are compared to the existing ones. Then, a potential expansion of the DHN to the neighbourhood and the introduction of renewable energy are studied.