Simulation-based design of PV cooling systems for residential buildings in hot and dry climates

The contribution focuses on the simulate-based design and optimization of photovoltaic (PV)-driven cooling systems for residential buildings in hot and dry countries. The analyzed system includes the PV generator, the electric battery, the vapor compression chiller, the air-conditioned building and the controller technologies. Systems with split-devices for direct air-cooling and also water-based systems for cooling ceilings are considered. The simulation studies are carried based on the Modelica library BuildingSystems and also in combination with the building simulation tool EnergyPlus and the framework for co-simulation BCVTB. In a first step, principal questions about the system design of photovoltaic-driven cooling systems under hot and dry climate conditions are analyzed, e.g. to find out matching system parameters like installed PV-power, battery capacity, vapor chiller cooling power taking into account the thermal capacity of the air-conditioned building. For this purpose, a pure Modelica system model with a simplified one-zone thermal building model is used. In a second step, a use case of a multi-zone building is studied, in which the building envelope is modeled with EnergyPlus and the air-conditioning system and the control strategy in Modelica. Both sub-models are integrated with BCVTB to the system model. The simulation study was carried for the hot and dry location Hashtgerd in North Iran and the City El Gouna on the west coast of Egypt.