Photovoltaic-thermal for household water heating systems: Current-based design

Photovoltaic (PV) systems tend to be overcharged because they receive abundant solar energy, especially during the dry season. Therefore, this excess energy can be used for other purposes, such as heating water. PV systems that also generate thermal energy are called photovoltaic-thermal (PV/T). This paper aimed to design a PV system for small-scale households integrated with a water heater. The PV/T system was coupled with a thermal energy storage tank with a volume of 16 liters. The loads on the PV/T system were the water pump, heating elements, and lights. The first step in the design was to calculate the required load. It then performs technical calculations for the PV system components: solar modules, batteries, and charge controllers. The selection of solar modules uses a current-based concept. Total of the actual daily load of the PV/T system is 27.5 Ah/day. The design of the PV/T system produces specifications, namely solar modules with a nominal power of 50 Wp, as many as two, a battery capacity of 70 Ah, and a battery charge controller current of 10 A.