A system dynamics model for the development and decarbonization of district heating systems

This study evaluates the long-term impact of integrating an energy hub into a district heating system, with a particular focus on system autonomy, CO2 emissions reduction, and cost dynamics up to 2050. A scenario-based approach was applied to assess three alternative development pathways, combining building renovation measures with different levels of heat supply decarbonization and energy resource diversification. The analysis considers changes in heat production structure, emissions balance, and economic performance under varying technological and market conditions. The results indicate that by implementing the energy hub, the share of purchased heat energy decreases from approximately 70% in 2023 to 35% in 2050, while the share of self-produced heat energy increases from approximately 30% to 65%. The emission analysis shows that energy efficiency measures in the building sector alone provide limited mitigation potential, achieving only moderate CO2 reductions. Substantially higher emission reductions, up to 36% by 2050, are achieved when building renovation is combined with a diversified and decarbonized heat supply, including the replacement of natural gas with low-carbon heat sources. The economic assessment reveals a clear trade-off between cost efficiency and strategic energy independence. Scenarios with lower initial investments and increased reliance on wood-chipbased heat remain the most cost-effective option throughout the analysed period, while technologically advanced solutions with higher upfront costs, such as the integration of an energy hub with synthetic methane production, have higher annual costs despite additional revenues from electricity sales. Sensitivity analysis confirms that natural gas prices remain the dominant cost driver, although the implementation of the energy hub and synthetic methane production progressively reduces the systems vulnerability to gas price volatility. The findings highlight the necessity of an integrated approach to district heating system transformation, demonstrating that long-term emission reductions, energy security, and economic resilience can only be achieved through the combined approach to building energy efficiency, heat supply decarbonization, and strategic long-term planning.