Enhancing the performance of photovoltaic panels by water cooling

Water spray cooling technique applied on a photovoltaic panel: The performance response

Cooling the operating surface is a key operational factor to take into consideration to achieve higher efficiency when operating solar photovoltaic systems. Proper cooling can improve the electrical efficiency, and decrease the rate of cell degradation with time, resulting in maximisation of the life span of photovoltaic modules. The excessive heat removed by the cooling system can be used in domestic, commercial or industrial applications. This paper presents a review of various methods that can be used to minimize the negative impacts of the increased temperature while making an attempt to enhance the efficiency of photovoltaic solar panels operating beyond the recommended temperature of the Standard Test Conditions (STC). Different cooling technologies are reviewed, namely Floating tracking concentrating cooling system (FTCC); Hybrid solar Photovoltaic/Thermal system cooled by water spraying; Hybrid solar Photovoltaic/ Thermoelectric PV/TE system cooled by heat sink; Hybrid solar Photovoltaic/Thermal (PV/T) cooled by forced water circulation; Improving the performance of solar panels through the use of phase-change materials; Solar panel with water immersion cooling technique; Solar PV panel cooled by transparent coating (photonic crystal cooling); Hybrid solar Photovoltaic/Thermal system cooled by forced air circulation, and Solar panel with Thermoelectric cooling. Several research papers are reviewed and classified based on their focus, contribution and the type of technology used to achieve the cooling of photovoltaic panels. The discussion of the results has been done based on the advantages, disadvantages, area of application as well as techno-economic character of each technology reviewed. The purpose of this review is to provide an understanding for each of the above-mentioned technologies to reduce the surface temperature of the PV module. The study will focus on the surface temperature reduction array bound by each of the cooling technologies. The performance of each cooling technology will also be highlighted. In addition to this study, this review will include a discussion comparing the performance of each cooling technology. The outcomes of this study are detailed in the conclusion section. This paper has revealed that any adequate technology selected to cool photovoltaic panels should be used to keep the operating surface temperature low and stable, be simple and reliable and, if possible, enable the use of extracted thermal heat to enhance the overall conversion efficiency. The presented detailed review can be used by engineers working on theory, design and/or application of photovoltaic systems.

A review of solar photovoltaic systems cooling technologies

Photovoltaic (PV) cells can absorb up to 80% of the incident solar radiation available in the solar spectrum, however, only a certain percentage of the absorbed incident energy is converted into electricity depending on the conversion efficiency of the PV cell technology. The remainder of the energy is dissipated as heat accumulating on the surface of the cells causing elevated temperatures. Temperature rise of PV cells is considered as one of the most critical issues influencing their performance, causing serious degradation and shortening the life-time of the cells. Hence cooling of PV modules during operation is essential and must be an integral part of PV systems particularly in sun-drenched locations. Many researches have been conducted investigating a range of methods that can be employed to provide thermal management for PV systems. Among these designs, systems utilizing air, liquid, heat pipes, phase change materials (PCMs), and thermoelectric (TE) devices to aid cooling of PV cells. This paper provides a comprehensive review of various methods reported in the literature and discusses various design and operating parameters influencing the cooling capacity for PV systems leading to an enhanced performance.

Advancements in hybrid photovoltaic systems for enhanced solar cells performance

Comprehensive analysis and general economic-environmental evaluation of cooling techniques for photovoltaic panels, Part II: Active cooling techniques

A novel micro heat pipe array was used in solar panel cooling. Both of air-cooling and water-cooling conditions under nature convection condition were investigated in this paper. Compared with the ordinary solar panel, the maximum difference of the photoelectric conversion efficiency is 2.6%, the temperature reduces maximally by 4.7℃, the output power increases maximally by 8.4% for the solar panel with heat pipe using air-cooling, when the daily radiation value is 26.3 MJ. Compared with the solar panel with heat pipe using air-cooling, the maximum difference of the photoelectric conversion efficiency is 3%, the temperature reduces maximally by 8℃, the output power increases maximally by 13.9% for the solar panel with heat pipe using water-cooling, when the daily radiation value is 21.9 MJ.

https://file.scirp.org/pdf/EPE20100300005_32723501.pdf

Experimental Investigation of Solar Panel Cooling by a Novel Micro Heat Pipe Array

A novel micro heat pipe array was used in solar panel cooling. Both of air-cooling and water-cooling conditions under nature convection condition were investigated in this paper. Compared with the ordinary solar panel, the maximum difference of the photoelectric conversion efficiency is 2.6%, the temperature reduces maximally by 4.7°C, the output power increases maximally by 8.4% for the solar panel with heat pipe using air-cooling, when the daily radiation value is 26.3 MJ. Compared with the solar panel with heat pipe using air-cooling, the maximum difference of the photoelectric conversion efficiency is 3%, the temperature reduces maximally by 8°C, the output power increases maximally by 13.9% for the solar panel with heat pipe using water-cooling, when the daily radiation value is 21.9 MJ.

Xiao Tang

Papers

Experimental Investigation of Solar Panel Cooling by a Novel Micro Heat Pipe Array

Notice of Retraction Experimental Investigation of Solar Panel Cooling by a Novel Micro Heat Pipe Array