Optimization of district heating systems integrated with energy storage for enhanced economic performance

Abstract

A possible carbon–neutral substitute for district heating systems (DHSs) that rely on fossil fuels is the idea of a heat-only small modular reactor (SMR). However, high capital expenditures and decreased capacity factors—mainly from variations in demand in independent operations—hinder its economic sustainability. To overcome these obstacles, this research suggests an integrated strategy that combines district heating systems (DHSs), heat-only small modular reactors (SMRs), and Organic Rankine Cycle (ORC) power generation. To improve the system’s energy management, auxiliary parts, including heat storage, gas boilers, and electricity storage, are also evaluated. The optimization framework, which focuses on factors including equipment design capacity and hourly operating tactics, is described as a mixed-integer nonlinear programming (MINLP) problem. The main goal criterion is the net present value (NPV). A heat-only SMR (Teplator-150 MWt), a 20 MWe ORC power plant, a 10,000 MWth thermal energy storage unit, a 3.4 MWt gas boiler, and electricity storage with a capacity of 20 MWe/120 MWeh are all part of the ideal design for a typical DHS in Czechia with a peak demand of 41 MWt. Compared to a traditional heat-only supply system, this integrated system improved energy management, increasing the SMR’s capacity from 10% to 83%. This resulted in a 357 million euro profit instead of a 50-million-euro loss. Sensitivity analysis revealed important economic viability variables, such as the ORC system’s size and technology, interest rates, and power market prices. These results demonstrate the importance of energy management and strategic system integration in reaching financial and environmental goals.