Researchers from Mexico’s University of Sonora (UNISON) and the National Technological Institute of Mexico have conducted a numerical study of the thermal performance of a single-channel cooling system for photovoltaic modules.
In their simulation, they used different kinds of nanofluids, such as aluminum oxide (Al₂O₃), copper(II) oxide (CuO), and zinc oxide (ZnO). In addition, they have equipped the system with baffles, which are structures placed inside a cooling channel to improve heat removal.
“The system includes nine equally spaced baffles, which act as deflectors. The baffles are inclined to 45 degrees with a height of 1 cm. They favor the contact of the cooling fluids with the back of the panel, increasing the effective heat transfer coefficient,” explained the group.
The model included the five layers that make up a 13%-efficient photovoltaic panel – glass, ethylene vinyl acetate (EVA), solar cell, tedlar, and thermal paste, as well as the proposed aluminum channel with a height of 3 cm through which the cooling fluid circulates. “This cooling fluid can be either a nanofluid or pure water,” the scientists explained.
The numerical model was constructed using the software Ansys Fluent v20, based on the finite volume method. The PV system model and the flow of nanofluids under the laminar flow regime were validated against previous literature results, showing a “reliable basis for modeling PV systems and their interaction with nanofluids.”
In all cases, the metal oxides were suspended in water, with changing volumetric concentrations of 0, 0.01, 0.05, and 0.1, respectively. They used a range of reynolds numbers (Re), which are the measure used to determine whether fluid flow is smooth or chaotic, ranging from 18 to 42. A fluid inlet temperature of 34 C was assumed.
The scientists found that the nanofluid composed of CuO was the most effective, improving efficiency by 5.67% compared to pure water in the lowest Re range. “The concentration of 0.1 vol in the nanofluid produces a more effective reduction in the temperature of the photovoltaic cell, which reaches up to 15 % when the Reynolds number increases from 18 to 42. The increase in Re from 18 to 42 boosted electrical efficiency by 4%,” they further explained.
In addition, the group also found that electric efficiency improved by 1.40% by increasing the nanofluid concentration from 0 to 0.1 and that increasing the radiation from 200 W/m2 to 1,000 W/m2 decreased the efficiency by 6.5% for pure water and 5.5% for the nanofluid. “Baffles improve heat transfer in specific channel areas, resulting in a 2% increase in electrical efficiency due to fluid flow redirection and acceleration,” they concluded.
The cooling system was presented in “Numerical study of the thermal performance of a single-channel cooling PV system using baffles and different nanofluids,” published in Heliyon.
This content is protected by copyright and may not be reused. If you want to cooperate with us and would like to reuse some of our content, please contact: editors@pv-magazine.com.
By submitting this form you agree to pv magazine using your data for the purposes of publishing your comment.
Your personal data will only be disclosed or otherwise transmitted to third parties for the purposes of spam filtering or if this is necessary for technical maintenance of the website. Any other transfer to third parties will not take place unless this is justified on the basis of applicable data protection regulations or if pv magazine is legally obliged to do so.
You may revoke this consent at any time with effect for the future, in which case your personal data will be deleted immediately. Otherwise, your data will be deleted if pv magazine has processed your request or the purpose of data storage is fulfilled.
Further information on data privacy can be found in our Data Protection Policy.