Coupling system dynamics model and multicriteria analysis for a sustainability assessment of a district heating system's development

The study provides the hybrid model that couples system dynamics (SD) modelling and multi-criteria analysis. The SD model allows obtaining energy, economic, environmental indicators of a DH company and evaluating its dynamics in a time horizon until 2050. Considered decarbonization scenarios include the transition of the DH system towards a 4th generation DH (4GDH) system adhering to 4 strategies: the DH system uses at least (a) 50% RES; (b) 50 % waste heat, (c) 75 % cogenerated heat or (d) 50 % of combined aforementioned energy and heat. In addition, the development scenarios include various energy efficiency improvement measures on the consumer side and in the heating networks. The sustainability of each scenario was assessed with multicriteria analysis methods - TOPSIS. The hybrid model provides a ranking of the selected transition pathways according to their sustainability score and benchmarks results of developed scenarios against a carbon neutral DH system. This model serves as a guidance to DH system developers and decision makers. The case of Riga is presented in the study.