A prototype of a mobile electric charging station was developed to simulate the energy supply to a rural medical post. A 20 m² medical post module was built, divided into two rooms (medical staff room and patient room) and a heater, a freezer, a refrigerator, lights and a personal computer were added inside. The mobile electric charging station was made up of an array of 2.88 kW flexible photovoltaic panels, a 48 V and 19.2 kW·h LiFePO₄ battery bank, a charger inverter with a total capacity of 5 kW and a 4 kW electric generator. All of this equipment was placed in an all-terrain pickup truck. Temperature sensors and electrical sensors were installed to evaluate the performance of the prototype in charging and discharging scenarios. Results were obtained according to the operation over 10 months in the city of Arequipa, Peru. The results indicate an indefinite autonomy on clear days, the autonomy varying between 7 and 10 days for a climate with medium cloudiness, and with very cloudy conditions (i.e., with rain), the autonomy is 2 to 3 days. In circumstances of low solar irradiance, the generator had to supply the energy, thereby improving energy autonomy.

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.