Development of a software system for optimal operation of heating networks with central solar plant

摘要

More and more district heating systems contain a central solar thermal plant in addition to the conventional CHPplant as heat source. In most cases, a short-term thermal energy storage is applied for balancing load and heatgeneration. The optimal operation of such complex systems regarding operational costs, high share of renewableenergy sources, supply safety, etc. is difficult due to mutual influences of the different components as well asfluctuating loads, solar gain and electricity prices. In a current research project, a new software system named HeatingNetwork Navigator is developed which will help the operators of solar district heating systems to reach optimaloperation. The approach of the project is to combine an intelligent deterministic optimization scheme based on asystem model with predictive control using forecasts of network load, solar yield and electricity price. Based oncurrent and historical measured data and forecasts for the boundary conditions, the Heating Network Navigator willgenerate suggestions for the process control system on when to charge and discharge the thermal energy storage,which set-point to define for the collector output temperature in matched-flow operation, etc. during the optimizationhorizon of several hours to some days.