Direct Current Photovoltaic Solar Energy for Water Heating

In this study, an experimental device is developed and implemented to evaluate the process of heating water using photovoltaic solar energy in direct current. The prototype consists of a 147 L stainless steel tank, a 5000 W heating element, and four solar panels (370 W each). Tests were carried out with a direct photovoltaic power supply and with the use of a maximum power point tracking (MPPT) device. Temperature and electrical sensors were installed and connected to a data acquisition system. The results show that the electrical energy produced by the PV solar panels can be used directly for water heating. For the direct PV power supply, the average total efficiency is 12%; with the MPPT, the average value is 18.2%. There is a clear improvement in efficiency when using a device with maximum power tracking, improving the heating process and reducing the time needed to reach the set temperature. This technology can be applied to water heating in residences, medical centers, and other buildings that require it.