Master's Thesis Marius Schmitz


Analysis on the influence of different energy load shifting implementations using heat pumps on the autarky of residential solar-based energy management systems

Copyright: EBC

Since the achievement of grid parity in 2012, major focus of development in both, industry and research is directed towards concepts for increased self-consumption of photovoltaic electricity. In particular the combination of heat pumps and PV systems facilitates new opportunities for cost-effective heat and power generation in residential buildings. By means of load-shifting mechanisms an increase in energetic building autarky and hence a reduction of private energy costs can be achieved.

This thesis develops a load-shifting concept based on the established SG-Ready interface for integrating and controlling the heat pump within an energy management system. In order to realistically analyze the heat pump, a simulation model of a heat pump control is generated and tested. Based on the results, annual simulations of the building energy system are carried out to investigate the potentials and limitations of the load-shifting concept. Thereby, evaluation criteria comprise autarky, self-consumption, user comfort and energy costs.

The potential analysis reveals an insufficient control of the heat pump system by the SG-Ready interface in conjunction with the implemented algorithm. Due to the limited system flexibility, only marginal increases in the energetic autarky are possible. Moreover, the temperature rise induces increased storage and efficiency losses which in turn causes a raised absolute energy consumption of the heat pump. Additionally, the inefficient operation of the heat pump results in decreasing SCOP, which compensate the cost advantage of an increased self-consumption.