Master's Thesis Lin Yan


Modelling of Different Domestic Hot Water System Concepts in Multi-Family-Dwellings using Heat Pumps

Domestic Hot Water System Concepts Copyright: EBC Model of the central storage loading system in Dymola / Modelica

In the context of energy shortages, energy is currently one of the most popular issues in the world. Due to the continual decline in fossil energy, the share of renewable energies in the energy supply is increased. The heat pump is a technology for renewable energy, which is currently widespread. Today, heat pumps are already being used to supply heat to many one- and two-family houses with low carbon dioxide. Their usage in multi-family houses is still rare. The aim of this work is to analyze and compare the influence of the domestic hot water concepts in the heat supply system in relation to the heat pump in order to find a better way of using the heat pump system in multi-family houses.

In this work, three different models for the heat supply systems each with central storage charging concept, central fresh water station and decentralized fresh water station in Dymola / Modelica are set up. The dynamic simulation analyzes and compares the heat supply effect, the heat loss, the operation of the heat pump and the system efficiency. As a result, for the reference buildings, the central storage charging system is a better choice for heat supply. In addition, as a sensitivity analysis, the relationship between the system efficiency and the ratio of heat load and domestic hot water load is analyzed by changing the heat load with a constant hot water load. The result shows that if the ratio of heating load and domestic hot water load is greater than 5.5, the central fresh water station system will be a better choice.​