Network simulation of low heat demand residential area

Energy consumption and heat demand in district heating systems will decrease in the future as low energy houses become more common and energy efficiency measures are implemented. The solutions for district heating to meet the challenges due to this trend are being studied. Simulation of three variations of a residential area with realistic load profiles for both heating and domestic hot water consumption was carried out. A low connection rate system and a low supply temperature variant were compared to a traditional design. Dedicated models were used in both building and network simulation. Results showed relative heat losses of 19.1 % for the low connection rate case. Low supply temperature variant resulted in 10 % lower heat losses than the reference case having relative heat losses of 10.6 %. All studied cases required a by-pass arrangement to maintain adequate temperature level for domestic hot water service outside heating season. This resulted in increased heat losses and in peaks in pressure drop. As in the future the operational environment is becoming more challenging for district heating, a need for comprehensive planning of whole systems taking into account all production, distribution and consumers will be more important than ever.