Water is a necessary resource for life development. Its excessive consumption has a negative impact, generating scarcity problems worldwide. Desalination is an alternative to solve these problems; its objective is to reduce the concentration of total dissolved solids to levels suitable for consumption. The most widely used desalination technology is reverse osmosis, which works by means of semipermeable membranes; however, lack of knowledge or wrong operation cause phenomena such as concentration polarization, which reduces the effective area for mass transfer in the membrane, increasing the energy consumption of the process. The objective of the present study is to evaluate the concentration polarization (β) of the concentration in reverse osmosis membranes by varying the temperature in the feed water (23, 25.5, 28, and 35 °C) for different concentrations (5000 and 10,000 mg L⁻¹) in order to reduce its impact on energy consumption (kWh m⁻³). The results show that as the temperature increases, the specific energy consumption decreases for both concentrations. In the 5000 mg L⁻¹ tests, the specific energy consumption decreased by 0.590 kWh m⁻³, representing 12.5%. For 10,000 mg L⁻¹ tests, the specific energy consumption shows a reduction of 0.72 kWh m⁻³, which represents a percentage decrease of 14.54%.

Water scarcity has prompted the use of desalination technologies such as reverse osmosis (RO) due to its low energy requirement and high production rate. In the present article, the concentration polarization factor (β) was evaluated in RO processes, in batch and continuous systems and with an alternating current (AC) and direct current (DC) to desalinate water with 10,000 mg L⁻¹ of total dissolved solids (TDS). In DC, the power variation and its effect on β was evaluated by simulating intermittent solar photovoltaic radiation. The specific energy consumption (SEC) in kWh m⁻³, the water quality in mg L⁻¹ of TDS and β were evaluated. In a batch process, 3.98 and 3.85 kWh m⁻³ were required for AC and DC, respectively. In a continuous process with AC, 3.79 kWh m⁻³ was required, and for DC, it decreased by 17.93%. The permeate water quality was evaluated with reference to the Mexican standard of 1000 mg L⁻¹ in TDS. A TDS concentration of 1631 mg L⁻¹ was found in batch–AC processes, and a TDS concentration of 747 mg L⁻¹ was found in batch–DC processes. In continuous AC–DC processes, the TDS concentration did not exceed 1000 mg L⁻¹. The permitted β limit was 1.2. The result of the batch process when using DC was 1.007, while for AC, it was 1.022. In continuous processes with AC, the β was 1.008, and in DC, it was 1.012. The results prove that the intermittency due to power variation is an alternative way to reduce the concentration polarization factor, with effects that include a reduction in the specific energy consumption and an improvement in the permeate water quality.