In the present experimental study, a photovoltaic (PV)-powered system in continuous current (4 kW) for the pumping of water in an isolated, rural agricultural zone in Arequipa—Peru was analyzed. A meteorological station was installed in the studied zone, measuring solar radiation, temperature, relative humidity, and wind speed. The electrical and hydraulic parameters of the solar-pumping system (i.e., electric current, voltage, mass flow, and hydraulic pressure) were measured in order to evaluate the efficiency of the energy transformation processes. The results indicate that, during the year of 2017, the PV pumping system in direct current (DC) functions from 07 h 30 min to 15 h 30 min, during an average of 8 h a day. The PV array, hydraulic, and global efficiencies were evaluated. This allows for the interpretation of efficiency independent of solar irradiance. The efficiency of the PV array and global efficiency remained constant (11.5% f and 8.5%, respectively). The functioning interval of the PV array ranges from 880 W up to 3400 W, making evident the versatility of the system of generation and consumption in DC, which is able to function since solar irradiance is at least 200 W/m2, corresponding to 880 W of PV array power, 27 m of total dynamic head (TDH) and 2 kg/s of mass flow, and 70% hydraulic efficiency. With greater mass flows (6.3 kg/s), the PV array power was 3256 W with a hydraulic efficiency of 55%, a TDH of 30 m, and a peak solar irradiance of 1190 W/m2. When the whole system functions in DC, the efficiencies are superior to those of systems, which operate with DC/alternating current (AC) current inverters.

A thermoelectric cooling system supplied by photovoltaic solar energy was built and evaluated with different thermal loads. The thermoelectric cooling module consumes 70 W, it is supplied by a photovoltaic system of 90 W and 40 Ah battery. The voltage and electrical current in each component (panels, battery, and electric charge) has been measured. The tests were performed with different thermal loads placed in glass containers used for vaccines. To analyze the cooling and preservation process, the experiments were started at room temperature. The results show that the thermoelectric cooling system works for small thermal loads, and it could be applied to transport vaccines in isolated areas where people carry medicines in small containers that do not maintain the temperature necessary for the conservation of vaccines.

An experimental study has been carried out to reduce the costs of freezing products from artisanal fishing in Peru using a photovoltaic solar system. The refrigeration chamber and the photovoltaic system have been equipped with electrical sensors to determine the cooling efficiency and thus calculate the savings. The results indicate that it is possible to reduce costs up to 45% using photovoltaic solar energy. The target users of this technology are artisanal fishermen in Peru. Using photovoltaic energy for freezing would allow them to add value to their products and improve their selling price. In this way, fish commercialization can be performed in better sanitary conditions and at fair prices.