Recent Trends in Cooling Techniques of Photovoltaic Panels: Comparison
Please note this is a comparison between versions V2 by Sirius Huang and V1 by Sami Salama Hussen Hajjaj.

One of the important ways to reduce pollution resulting from the increasing consumption of fossil energy is to enhance the sources of solar energy, of which photovoltaic cells (PV) are one of its most important tools. Therefore, it was necessary to pay attention to improving its efficiency for it to become a promising source of clean energy. PVs turn solar energy into electricity; however, the amount of electricity generated decreases as the temperature of the cells rises in response to the sun’s heat. Cooling of the optical surfaces is one of the most important elements to consider while running solar PV systems to obtain maximum efficiency. 

  • Solar Energy
  • Photovoltaic Thermal Systems (PV/T)
  • Cooling Materials
  • Photovoltaic Panels (PVs)
  • Solar Power efficiency
  • Nanomaterials for Cooling PVs

1. Introduction

Fossil fuels produce more than 80% of the world’s energy. Combustion residues of these fuels negatively affect the environment by producing acid rain and causing global warming, which increases rapidly with development and increases in the world population because of the increasing demand for energy [1,2[1][2][3],3], so it was necessary to search for renewable energy sources [4]. Solar energy is one of the most significant renewable energy sources since it can readily be turned into thermal and electrical energy, in addition to being sustainable, available and clean energy [5].

2. Improving the Generation of Clean Energy by Cooling Techniques to Reduce Environmental Effects

PV panels convert solar energy into electricity. However, if the temperature of the cells rises owing to the sun’s temperature, the output of electricity falls. Therefore, different cooling techniques were used for solar cells to control their temperature, as shown in Table 1.

Table 1.
 Photovoltaic cooling techniques.
Because of the increasing demand for energy and the excessive use of traditional energy sources, this has led to an increase in environmental pollution due to emissions from burning fuels. Cooling solar cells increases their potential to create clean energy and use it as an alternative to traditional polluting energy sources. Researchers provided an in-depth analysis of the design components of a concentrated photovoltaic thermal, heat transfer medium and new application sectors in this paper. The findings show that CPVT systems are a promising system for producing high amounts of clean electrical and thermal energy that are in line with the seven sustainable development goals by using this energy in a variety of thermal applications such as space heating and cooling, desalination, electrical energy generation, greenhouses and so on [71,72,73][41][42][43]. Other researchers compared the performance of a water-based photovoltaic system (thermal), a PV/T system with PCM, an air-based PV/T system and a conventional PV panel in different studies. In comparison to alternative kinds of cooling, it was found that the efficiency of the systems in producing energy depends on the type of material used, and all the arrangements proved to be more important solutions for delivering superior thermal and electrical efficiency systems (compared with the conventional system), thus serving as a promising source as an alternative to fossil energy that gives rise to air pollution and an increased earth temperature [48,74,75][44][45][46]. Some researchers focused on the increasing consumption of fossil energy and the accompanying emissions and pollution as a result of urban transformation and expansion of the construction and service sectors in developing countries in particular. Accordingly, the researchers’ efforts focused on improving the performance of photovoltaic cells, whose efficiency is affected by atmospheric conditions, to make them a suitable substitute for the production of clean energy [76,77,78,79,80][47][48][49][50][51]. Researchers [3,81,82][3][52][53] looked at the energy-increasing and environmental impacts of using nanofluids (NFs) in PVTS by measuring their physical and thermal properties. The researchers discovered that dispersion of nanoparticles in the base fluid increases the PVTS’ thermal and electrical performance, which improves the systems’ environmental characteristics. In fact, a nano-fluid-based solar system may avoid the release of greenhouse gases emissions, particularly carbon dioxide (CO2), into the environment more effectively than pure heat pumps by producing more energy. The performance of the integration of the Kalina cycle with CPVT for a multi-generation and hydrogen production system was investigated utilizing air and water as a cooling medium and three distinct mass flow rates. According to the findings of these studies, electricity, hydrogen and hot air production were increased. These kinds of systems would be used to minimize pollution in the environment because the emissions will decrease significantly [83,84][54][55]. The steady increase in population numbers and the need to address the problem of food insecurity in some countries made some researchers search for quick, effective and environmentally friendly ways to dry food, as the drying process consumes energy intensively, and the use of fossil energy in the drying process increases pollution. In these cases, the focus was on improving the performance of solar energy systems to provide the appropriate energy [85,86,87][56][57][58]. On the other hand, water is also a paramount necessity for human life, and the need to provide for drinking water in water-poor countries requires desalination since desalination consumes a large amount of energy. Some researchers have developed ways to use solar energy when desalinating water as well as storing energy for use when needed. This reduces the consumption of fossil energy and the emission of gases [88,89][59][60].


  1. Li, M. World Energy 2017–2050: Annual Report; Department of Economics, University of Utah: Salt Lake City, UT, USA, 2017.
  2. Hassani, S.; Saidur, R.; Mekhilef, S.; Taylor, R.A. Environmental and exergy benefit of nanofluid-based hybrid PV/T systems. Energy Convers. Manag. 2016, 123, 431–444.
  3. Salari, A.; Taheri, A.; Farzanehnia, A.; Passandideh-Fard, M.; Sardarabadi, M. An updated review of the performance of nanofluid-based photovoltaic thermal systems from energy, exergy, economic, and environmental (4E) approaches. J. Clean. Prod. 2021, 282, 124318.
  4. Esfe, M.H.; Kamyab, M.H.; Valadkhani, M. Application of nanofluids and fluids in photovoltaic thermal system: An updated review. Sol. Energy 2020, 199, 796–818.
  5. Aldossary, A.; Mahmoud, S.; Al-Dadah, R. Technical feasibility study of passive and active cooling for concentrator PV in harsh environment. Appl. Therm. Eng. 2016, 100, 490–500.
  6. He, W.; Chow, T.-T.; Ji, J.; Lu, J.; Pei, G.; Chan, L.S.A. Hybrid photovoltaic and thermal solar-collector designed for natural circulation of water. Appl. Energy 2006, 83, 199–210.
  7. Kim, J.H.; Ahn, J.G.; Kim, J.T. Demonstration of the performance of an air-type photovoltaic thermal (PVT) system coupled with a heat-recovery ventilator. Energies 2016, 9, 728.
  8. Shahsavar, A.; Ameri, M. Experimental investigation and modeling of a direct-coupled PV/T air collector. Sol. Energy 2010, 84, 1938–1958.
  9. Cuce, E.; Bali, T.; Sekucoglu, S.A. Effects of passive cooling on performance of silicon photovoltaic cells. Int. J. Low-Carbon Technol. 2011, 6, 299–308.
  10. Dixit, K.K.; Yadav, I.; Gupta, G.K.; Maurya, S.K. A review on cooling techniques used for photovoltaic panels. In Proceedings of the 2020 International Conference on Power Electronics & IoT Applications in Renewable Energy and Its Control (PARC), Mathura, India, 28–29 February 2020; pp. 360–364.
  11. Indugowda, C.S.; Ranjith, P.K. Cooling Methods for Increasing Efficiency of PV Panel. In Research Scholar (M-Tech Thermal Engineering); Assistant Professor, Department of Mechanical Engineering Global Academy of Technology; International Journal of Scientific Development and Research (IJSDR): Gujaratm, India, 2016.
  12. Odeh, S.; Behnia, M. Improving Photovoltaic Module Efficiency Using Water Cooling. Heat Transf. Eng. 2009, 30, 499–505.
  13. Wu, S.-Y.; Chen, C.; Xiao, L. Heat transfer characteristics and performance evaluation of water-cooled PV/T system with cooling channel above PV panel. Renew. Energy 2018, 125, 936–946.
  14. Lupu, A.G.; Homutescu, V.M.; Balanescu, D.T.; Popescu, E.A. A review of solar photovoltaic systems cooling technologies. In IOP Conference Series: Materials Science and Engineering; IOP Publishing: Bristol, UK, 2018; Volume 444, p. 082016.
  15. Dubey, S.; Tiwari, G. Thermal modeling of a combined system of photovoltaic thermal (PV/T) solar water heater. Sol. Energy 2008, 82, 602–612.
  16. Bahaidarah, H.M. Experimental performance evaluation and modeling of jet impingement cooling for thermal management of photovoltaics. Sol. Energy 2016, 135, 605–617.
  17. Hasan, H.A.; Sopian, K.; Jaaz, A.H.; Al-Shamani, A.N. Experimental investigation of jet array nanofluids impingement in photovoltaic/thermal collector. Sol. Energy 2017, 144, 321–334.
  18. Nadda, R.; Kumar, A.; Maithani, R. Efficiency improvement of solar photovoltaic/solar air collectors by using impingement jets: A review. Renew. Sustain. Energy Rev. 2018, 93, 331–353.
  19. Mehrotra, S.; Rawat, P.; Debbarma, M.; Sudhakar, K. Performance of a solar panel with water immersion cooling technique. Int. J. Sci. Environ. Technol. 2014, 3, 1161–1172.
  20. Zhu, L.; Boehm, R.F.; Wang, Y.; Halford, C.; Sun, Y. Water immersion cooling of PV cells in a high concentration system. Sol. Energy Mater. Sol. Cells 2011, 95, 538–545.
  21. Rosa-Clot, M.; Tina, G.M.; Scandura, P. Submerged photovoltaic solar panel: SP2. Renew. Energy 2010, 35, 1862–1865.
  22. Maiti, S.; Banerjee, S.; Vyas, K.; Patel, P.; Ghosh, P.K. Self regulation of photovoltaic module temperature in V-trough using a metal–wax composite phase change matrix. Sol. Energy 2011, 85, 1805–1816.
  23. Hachem, F.; Abdulhay, B.; Ramadan, M.; El Hage, H.; El Rab, M.G.; Khaled, M. Improving the performance of photovoltaic cells using pure and combined phase change materials—Experiments and transient energy balance. Renew. Energy 2017, 107, 567–575.
  24. Anderson, W.G.; Dussinger, P.M.; Sarraf, D.B.; Tamanna, S. Heat pipe cooling of concentrating photovoltaic cells. In Proceedings of the 2008 33rd IEEE Photovoltaic Specialists Conference, San Diego, CA, USA, 11–16 May 2008; pp. 1–6.
  25. Gang, P.; Huide, F.; Tao, Z.; Jie, J. A numerical and experimental study on a heat pipe PV/T system. Sol. Energy 2011, 85, 911–921.
  26. Hou, L.; Quan, Z.; Zhao, Y.; Wang, L.; Wang, G. An experimental and simulative study on a novel photovoltaic-thermal collector with micro heat pipe array (MHPA-PV/T). Energy Build. 2016, 124, 60–69.
  27. Jouhara, H.; Szulgowska-Zgrzywa, M.; Sayegh, M.; Milko, J.; Danielewicz, J.; Nannou, T.; Lester, S. The performance of a heat pipe based solar PV/T roof collector and its potential contribution in district heating applications. Energy 2017, 136, 117–125.
  28. Popovici, C.G.; Hudişteanu, S.V.; Mateescu, T.D.; Cherecheş, N.C. Efficiency improvement of photovoltaic panels by using air cooled heat sinks. Energy Procedia 2016, 85, 425–432.
  29. Radwan, A.; Ahmed, M. The influence of microchannel heat sink configurations on the performance of low concentrator photovoltaic systems. Appl. Energy 2017, 206, 594–611.
  30. Gilmore, N.; Timchenko, V.; Menictas, C. Microchannel cooling of concentrator photovoltaics: A review. Renew. Sustain. Energy Rev. 2018, 90, 1041–1059.
  31. Elqady, H.I.; Abo-Zahhad, E.M.; Radwan, A.; El-Shazly, A.; Elkady, M. Thermal and electrical performances of actively cooled concentrator photovoltaic system. Appl. Therm. Eng. 2021, 196, 117295.
  32. Teo, H.; Lee, P.; Hawlader, M. An active cooling system for photovoltaic modules. Appl. Energy 2012, 90, 309–315.
  33. Minea, A.A.; El-Maghlany, W.M. Influence of hybrid nanofluids on the performance of parabolic trough collectors in solar thermal systems: Recent findings and numerical comparison. Renew. Energy 2018, 120, 350–364.
  34. Karaaslan, I.; Menlik, T. Numerical study of a photovoltaic thermal (PV/T) system using mono and hybrid nanofluid. Sol. Energy 2021, 224, 1260–1270.
  35. Naiman, I.; Ramasamy, D.; Kadirgama, K. Experimental and one dimensional investigation on nanocellulose and aluminium oxide hybrid nanofluid as a new coolant for radiator. In IOP Conference Series: Materials Science and Engineering; IOP Publishing: Bristol, UK, 2019; Volume 469, p. 01209.
  36. Alwaeli, A.H.A.; Chaichan, M.T.; Kazem, H.A.; Sopian, K. Comparative study to use nano-(Al2O3, CuO, and SiC) with water to enhance photovoltaic thermal PV/T collectors. Energy Convers. Manag. 2017, 148, 963–973.
  37. Sami, S. Analysis of Nanofluids Behavior in a PV-Thermal-Driven Organic Rankine Cycle with Cooling Capability. Appl. Syst. Innov. 2020, 3, 12.
  38. Li, Y.; Jing, D. Investigation of the performance of photovoltaic/thermal system by a coupled TRNSYS and CFD simulation. Sol. Energy 2017, 143, 100–112.
  39. Mojiri, A.; Taylor, R.; Thomsen, E.; Rosengarten, G. Spectral beam splitting for efficient conversion of solar energy—A review. Renew. Sustain. Energy Rev. 2013, 28, 654–663.
  40. Joshi, S.S.; Dhoble, A.S. Experimental investigation of solar photovoltaic thermal system using water, coconut oil and silicone oil as spectrum filters. J. Braz. Soc. Mech. Sci. Eng. 2017, 39, 3227–3236.
  41. George, M.; Pandey, A.; Rahim, N.A.; Tyagi, V.; Shahabuddin, S.; Saidur, R. Concentrated photovoltaic thermal systems: A component-by-component view on the developments in the design, heat transfer medium and applications. Energy Convers. Manag. 2019, 186, 15–41.
  42. Elminshawy, N.A.; El-Ghandour, M.; Elhenawy, Y.; Bassyouni, M.; El-Damhogi, D.; Addas, M.F. Experimental investigation of a V-trough PV concentrator integrated with a buried water heat exchanger cooling system. Sol. Energy 2019, 193, 706–714.
  43. Khodadadi, M.; Farshad, S.A.; Ebrahimpour, Z.; Sheikholeslami, M. Thermal performance of Nanofluid with employing of NEPCM in a PVT-LFR system. Sustain. Energy Technol. Assess. 2021, 47, 101340.
  44. Fudholi, A.; Zohri, M.; Rukman, N.S.B.; Nazri, N.S.; Mustapha, M.; Yen, C.H.; Sopian, K. Exergy and sustainability index of photovoltaic thermal (PVT) air collector: A theoretical and experimental study. Renew. Sustain. Energy Rev. 2019, 100, 44–51.
  45. Sharma, R.; Singh, S.; Mehra, K.S.; Kumar, R. Performance enhancement of solar photovoltaic system using different cooling techniques. Mater. Today Proc. 2021, 46, 11023–11028.
  46. Tahmasbi, M.; Siavashi, M.; Norouzi, A.M.; Doranehgard, M.H. Thermal and electrical efficiencies enhancement of a solar photovoltaic-thermal/air system (PVT/air) using metal foams. J. Taiwan Inst. Chem. Eng. 2021, 124, 276–289.
  47. Paul, S.J.; Kumar, U.; Jain, S. Photovoltaic cells cooling techniques for energy efficiency optimization. Mater. Today Proc. 2020, 46, 5458–5463.
  48. Rao, V.T.; Sekhar, Y.R. Comparative analysis on embodied energy and CO2 emissions for stand-alone crystalline silicon photovoltaic thermal (PVT) systems for tropical climatic regions of India. Sustain. Cities Soc. 2021, 78, 103650.
  49. Yao, J.; Dou, P.; Zheng, S.; Zhao, Y.; Dai, Y.; Zhu, J.; Novakovic, V. Co-generation ability investigation of the novel structured PVT heat pump system and its effect on the “Carbon neutral” strategy of Shanghai. Energy 2021, 239, 121863.
  50. Singh, H.P.; Arora, S.; Sahota, L.; Arora, M.K.; Jain, A.; Singh, A. Evaluation of the performance parameters of a PVT system: Case study of composite environmental conditions for different Indian cities. Mater. Today Proc. 2022, 57, 1975–1982.
  51. Fu, Z.; Li, Y.; Liang, X.; Lou, S.; Qiu, Z.; Cheng, Z.; Zhu, Q. Experimental investigation on the enhanced performance of a solar PVT system using micro-encapsulated PCMs. Energy 2021, 228, 120509.
  52. Muzaidi, N.A.S.; Fikri, M.A.; Wong, K.N.S.W.S.; Sofi, A.Z.M.; Mamat, R.; Adenam, N.M.; Adli, H.K. Heat absorption properties of CuO/TiO2/SiO2 trihybrid nanofluids and its potential future direction towards solar thermal applications. Arab. J. Chem. 2021, 14, 103059.
  53. Hassani, S.; Taylor, R.A.; Mekhilef, S.; Saidur, R. A cascade nanofluid-based PV/T system with optimized optical and thermal properties. Energy 2016, 112, 963–975.
  54. Raja, S.; Gangadevi, R.; Marimuthu, R.; Baskaran, M. Performance evaluation of water and air based PVT solar collector for hydrogen production application. Int. J. Hydrogen Energy 2020, 45, 7498–7507.
  55. Bamisile, O.; Huang, Q.; Dagbasi, M.; Adebayo, V.; Okonkwo, E.C.; Ayambire, P.; Ratlamwala, T.A. Thermo-environ study of a concentrated photovoltaic thermal system integrated with Kalina cycle for multi-generation and hydrogen production. Int. J. Hydrogen Energy 2020, 45, 26716–26732.
  56. Tiwari, S.; Agrawal, S.; Tiwari, G. PVT air collector integrated greenhouse dryers. Renew. Sustain. Energy Rev. 2018, 90, 142–159.
  57. Udomkun, P.; Romuli, S.; Schock, S.; Mahayothee, B.; Sartas, M.; Wossen, T.; Njukwe, E.; Vanlauwe, B.; Müller, J. Review of solar dryers for agricultural products in Asia and Africa: An innovation landscape approach. J. Environ. Manag. 2020, 268, 110730.
  58. Çiftçi, E.; Khanlari, A.; Sözen, A.; Aytaç, I.; Tuncer, A.D. Energy and exergy analysis of a photovoltaic thermal (PVT) system used in solar dryer: A numerical and experimental investigation. Renew. Energy 2021, 180, 410–423.
  59. Anand, B.; Shankar, R.; Murugavelh, S.; Rivera, W.; Prasad, K.M.; Nagarajan, R. A review on solar photovoltaic thermal integrated desalination technologies. Renew. Sustain. Energy Rev. 2021, 141, 110787.
  60. Nieto-Maestre, J.; Muñoz-Sánchez, B.; Fernández, A.G.; Faik, A.; Grosu, Y.; García-Romero, A. Compatibility of container materials for Concentrated Solar Power with a solar salt and alumina based nanofluid: A study under dynamic conditions. Renew. Energy 2019, 146, 384–396.