Estimating the Solar Fraction of a Closed Solar Water Heating System Using the Utilizability F-Chart Method under Various Operating Conditions
DOI:
https://doi.org/10.31185/wjes.Vol14.Iss1.645Keywords:
Solar water heating system, Thermal performance, Solar collector, Solar fraction factor, Storage capacity, Solar collection areaAbstract
The increasing demand for sustainable cooling technologies and the shift away from fossil fuels have heightened interest in solar-assisted thermal systems, particularly for powering absorption refrigeration units in hot environments. This study evaluated the performance of a closed-loop solar water heating system used to supply hot water to an absorption refrigeration machine. The analysis was carried out using the utilizability (f-chart) method and the MATHLAP computer program. The study considered various operating conditions and four types of flat-plate solar collectors: Type A: Single transparent cover solar collector with absorbent surface painted in standard black color; Type B: Single transparent cover solar collector with absorbent surface coated in black selective material; Type C: Solar collector with two transparent covers with absorbent surface painted in standard black color; and Type D: Solar collector with two transparent covers with absorbent surface coated in black selective material. The system was analyzed for different solar collector areas and storage capacities over several summer months. The solar fraction (f) was used as the primary performance metric. The results indicated that Type D collectors performed the best owing to their improved thermal insulation and selective absorption. Type A exhibited the lowest performance because of its higher heat losses. Types B and C yielded intermediate results. The study also examined the effect of five storage capacities (25, 50, 75, 100, and 125 kg of water per m²) and five collector areas (40, 60, 80, 100, and 120 m²) on system efficiency. Both parameters positively affected the thermal performance. This study aims to determine the thermal performance of a closed-loop solar water heating system for powering an absorption refrigeration machine by estimating the solar fraction under different conditions.
References
[1] P. Charoensawan, P. Wilaipon, and N. Seehawong, “Flat Plate Solar Water Heater With Closed-Loop Oscillating Heat Pipes,” Thermal Science, vol. 25, no. 5, pp. 3607–3614, 2021, doi: 10.2298/TSCI200713192C. DOI: https://doi.org/10.2298/TSCI200713192C
[2] Vishal Singh and Vishwajeet Kureel, “Performance Optimization of Solar Water Heating Systems in Different Climates,” International Journal of Modern Engineering & Management Research, vol. 12, no. 3, 2024, Accessed: Jul. 27, 2025. [Online]. Available: https://www.ijmemr.org/Publication/V12I3/IJMEMR-V12I3-002.pdf
[3] A. Herez et al., “Solar water heating: comprehensive review, critical analysis and case study,” International Journal of Thermofluids, vol. 20, Nov. 2023, doi: 10.1016/j.ijft.2023.100503. DOI: https://doi.org/10.1016/j.ijft.2023.100503
[4] H. Fayaz, N. A. Rahim, R. Saidur, and M. Hasanuzzaman, “Techno-economic Analysis of Evacuated Tube Solar Water Heater using F-chart Method,” in IOP Conference Series: Materials Science and Engineering, Institute of Physics Publishing, May 2018. doi: 10.1088/1757-899X/358/1/012016. DOI: https://doi.org/10.1088/1757-899X/358/1/012016
[5] Kerme and Kaneesamkandi, “Performance analysis and design of liquid based solar heating system,” vol. 1, no. 1, pp. 182–191, Feb. 2015, doi: https://doi.org/10.18186/jte.02359. DOI: https://doi.org/10.18186/jte.02359
[6] M. Tunç and Ü. Çamdalı, “Optimal Domestic Solar Space and Water Heating System in Çeşme,” INTERNATIONAL JOURNAL of RENEWABLE ENERGY RESEARCH M. Tunc and U. Camdali, vol. 7, no. 4, Nov. 2017, [Online]. Available: www.enerji.gov.tr
[7] M. Gojak, F. Ljubinac, and M. Banjac, “Simulation of solar water heating system,” FME Transactions, vol. 47, no. 1, pp. 1–6, 2019, doi: 10.5937/fmet1901001G. DOI: https://doi.org/10.5937/fmet1901001G
[8] S. Sirdaş, “Daily wind speed harmonic analysis for Marmara region in Turkey,” Energy Convers Manag, vol. 46, no. 7, pp. 1267–1277, 2005, doi: https://doi.org/10.1016/j.enconman.2004.06.020. DOI: https://doi.org/10.1016/j.enconman.2004.06.020
[9] S. A. Klein, W. A. Beckman, and J. A. Duffie, “A design procedure for solar heating systems,” Solar Energy, vol. 18, no. 2, pp. 113–127, 1976, doi: https://doi.org/10.1016/0038-092X(76)90044-X. DOI: https://doi.org/10.1016/0038-092X(76)90044-X
[10] J. G. Cardoso, I. R. S. Casella, A. J. S. Filho, F. F. Costa, and C. E. Capovilla, “SCIG wind turbine wireless controlled using morphological filtering for power quality enhancement,” Renew Energy, vol. 92, pp. 303–311, 2016, doi: https://doi.org/10.1016/j.renene.2016.02.014. DOI: https://doi.org/10.1016/j.renene.2016.02.014
[11] A. Mehmeti, J. Pedro Pérez-Trujillo, F. Elizalde-Blancas, A. Angelis-Dimakis, and S. J. McPhail, “Exergetic, environmental and economic sustainability assessment of stationary Molten Carbonate Fuel Cells,” Energy Convers Manag, vol. 168, pp. 276–287, 2018, doi: https://doi.org/10.1016/j.enconman.2018.04.095. DOI: https://doi.org/10.1016/j.enconman.2018.04.095
[12] M. Adouane, A. Al-Qattan, B. Alabdulrazzaq, and A. Fakhraldeen, “Comparative performance evaluation of different photovoltaic modules technologies under Kuwait harsh climatic conditions,” Energy Reports, vol. 6, pp. 2689–2696, 2020, doi: https://doi.org/10.1016/j.egyr.2020.09.034. DOI: https://doi.org/10.1016/j.egyr.2020.09.034
[13] K. Sangeetha, A. S. Liz, P. Suganthi, and D. L. Femilinjana, “Integrating Machine Learning Algorithms for Predicting Solar Power Generation,” in E3S Web of Conferences, EDP Sciences, May 2023. doi: 10.1051/e3sconf/202338701004. DOI: https://doi.org/10.1051/e3sconf/202338701004
[14] G. Ruan, J. Wu, H. Zhong, Q. Xia, and L. Xie, “Quantitative assessment of U.S. bulk power systems and market operations during the COVID-19 pandemic,” Appl Energy, vol. 286, p. 116354, 2021, doi: https://doi.org/10.1016/j.apenergy.2020.116354. DOI: https://doi.org/10.1016/j.apenergy.2020.116354
[15] S.-Y. Wu, L. Xu, and L. Xiao, “Air purification and thermal performance of photocatalytic-Trombe wall based on multiple physical fields coupling,” Renew Energy, vol. 148, pp. 338–348, 2020, doi: https://doi.org/10.1016/j.renene.2019.10.039. DOI: https://doi.org/10.1016/j.renene.2019.10.039
[16] P. Si, Y. Lv, X. Rong, L. Shi, J. Yan, and X. Wang, “An innovative building envelope with variable thermal performance for passive heating systems,” Appl Energy, vol. 269, p. 115175, 2020, doi: https://doi.org/10.1016/j.apenergy.2020.115175. DOI: https://doi.org/10.1016/j.apenergy.2020.115175
[17] R. R. Rustum and A. D. Al-Nadawi, “Using the utility method - F-scheme in studying the long-term thermal performance of the heat-storage and transmitting wall (Trombe wall),” Wasit Journal of Engineering Sciences, vol. 10, no. 2, pp. 69–82, Jun. 2022, doi: 10.31185/ejuow.Vol10.Iss2.261. DOI: https://doi.org/10.31185/ejuow.Vol10.Iss2.261
[18] R. Alayi, N. Khalilpoor, S. Heshmati, A. Najafi, and A. Issakhov, “Thermal and Environmental Analysis Solar Water Heater System for Residential Buildings,” International Journal of Photoenergy, vol. 2021, 2021, doi: 10.1155/2021/6838138. DOI: https://doi.org/10.1155/2021/6838138
[19] J. D. Gil, A. Topa, J. D. Álvarez, J. L. Torres, and M. Pérez, “A review from design to control of solar systems for supplying heat in industrial process applications,” Jul. 01, 2022, Elsevier Ltd. doi: 10.1016/j.rser.2022.112461. DOI: https://doi.org/10.1016/j.rser.2022.112461
[20] D. Huang et al., “Study on the Energy Efficiency Improvement and Operation Optimization of a Solar Water Heating System,” Applied Sciences (Switzerland), vol. 12, no. 14, Jul. 2022, doi: 10.3390/app12147263. DOI: https://doi.org/10.3390/app12147263
[21] A. Whillier, “Solar energy collection and its utilization for house heating (Sc.D. Thesis). Massachusetts Institute of Technology". Retrieved from MIT Digital Repository,” 1963.
[22] B. Y. H. Liu and R. C. Jordan, “The long-term average performance of flat-plate solar-energy collectors: With design data for the U.S., its outlying possessions and Canada,” Solar Energy, vol. 7, no. 2, pp. 53–74, 1963, doi: https://doi.org/10.1016/0038-092X(63)90006-9. DOI: https://doi.org/10.1016/0038-092X(63)90006-9
[23] M. Zlateva, “Assessment of the annual performance of solar collectors by means of the utilizability method,” in E3S Web of Conferences, EDP Sciences, Nov. 2020. doi: 10.1051/e3sconf/202020702007. DOI: https://doi.org/10.1051/e3sconf/202020702007
[24] M. Collares-Pereira and A. Rabl, “The average distribution of solar radiation-correlations between diffuse and hemispherical and between daily and hourly insolation values,” Solar Energy, vol. 22, no. 2, pp. 155–164, 1979, doi: https://doi.org/10.1016/0038-092X(79)90100-2. DOI: https://doi.org/10.1016/0038-092X(79)90100-2
[25] S. A. Klein and W. A. Beckman, “A general design method for closed-loop solar energy systems,” Solar Energy, vol. 22, no. 3, pp. 269–282, 1979, doi: https://doi.org/10.1016/0038-092X(79)90142-7. DOI: https://doi.org/10.1016/0038-092X(79)90142-7
[26] M. D.-E. Sarmouk, A. Smaili, H. Fellouah, and A. Merabtine, “Experimental and numerical investigations of a solar space heating system based on design of experiments method,” Solar Energy, vol. 216, pp. 396–410, 2021, doi: https://doi.org/10.1016/j.solener.2021.01.039. DOI: https://doi.org/10.1016/j.solener.2021.01.039
[27] D. Marano, V. Sabatelli, and G. Fiorenza, “Techno-Economic Evaluation of Solar-Assisted Air-Conditioning Systems in Europe,” 2007. [Online]. Available: https://www.researchgate.net/publication/357631813
[28] I. S. Marinopoulos and K. L. Katsifarakis, “Optimization of Energy and Water Management of Swimming Pools. A Case Study in Thessaloniki, Greece,” Procedia Environ Sci, vol. 38, pp. 773–780, 2017, doi: 10.1016/j.proenv.2017.03.161. DOI: https://doi.org/10.1016/j.proenv.2017.03.161
[29] L. Enriquez, J. Gabriel, D. Casas, and S. Isabel, “USABILIDAD EN APLICACIONES MÓVILES.”
[30] S. A. Klein, “Calculation of flat-plate collector utilizability,” Solar Energy, vol. 21, no. 5, pp. 393–402, 1978, doi: https://doi.org/10.1016/0038-092X(78)90171-8. DOI: https://doi.org/10.1016/0038-092X(78)90171-8
[31] J. C. Mitchell, J. C. Theilacker, and S. A. Klein, “Calculation of monhly average collector operating time and parasitic energy requirements,” Solar Energy, vol. 26, no. 6, pp. 555–558, 1981, doi: https://doi.org/10.1016/0038-092X(81)90169-9. DOI: https://doi.org/10.1016/0038-092X(81)90169-9
[32] E. M. Ismail, S. J. Flayh, M. Saeedmohammed, and K. S. Mohammed, “Heat Exchanger Design and Optimization for Industrial Applications,” Nanotechnol Percept, vol. 20, no. S3, pp. 211–229, 2024, doi: doi:10.62441/nano-ntp.v20is3.18. DOI: https://doi.org/10.62441/nano-ntp.v20iS3.18
[33] A. K. Alshara, A. Mohsin Alsayah, M. Saeed Mohammed, S. Fahad Dakel, and A. Kadhim Alshara, “Numerical and experimental study of heat transfer in shell-and U-tube heat exchanger with baffles,” Chinese Journal of Geotechnical Engineering, vol. 44, no. 5, Jan. 2022, doi: 10.11779/CJGE202205.2.
[34] L. Caretto, “The f-Chart Method for Solar Chart Method for Solar Collectors Collectors Alternative Energy Alternative Energy,” 2010. [Online]. Available: http://www.fchart.com/
[35] S. A. Kalogirou, “Solar thermal collectors and applications,” Prog Energy Combust Sci, vol. 30, no. 3, pp. 231–295, 2004, doi: https://doi.org/10.1016/j.pecs.2004.02.001. DOI: https://doi.org/10.1016/j.pecs.2004.02.001
[36] Ashrae standard, “Methods of Testing to Determine the Thermal Performance of Solar Collector,” American society of heating, Refrigerating and Air-Conditioning Engineers, 1977.
[37] M. R. Clot, P. Rosa-Clot, and G. M. Tina, “Submerged PV Solar Panel for Swimming Pools: SP3,” in Energy Procedia, Elsevier Ltd, 2017, pp. 567–576. doi: 10.1016/j.egypro.2017.09.565. DOI: https://doi.org/10.1016/j.egypro.2017.09.565
[38] T. Echániz, I. Setién-Fernández, R. B. Pérez-Sáez, C. Prieto, R. E. Galindo, and M. J. Tello, “Importance of the spectral emissivity measurements at working temperature to determine the efficiency of a solar selective coating,” Solar Energy Materials and Solar Cells, vol. 140, pp. 249–252, Sep. 2015, doi: 10.1016/j.solmat.2015.04.009. DOI: https://doi.org/10.1016/j.solmat.2015.04.009
[39] B. A. Ternenge, Zwalnan. J. S, N. N. Caleb, and E. E. Oguche, “Flat Plate Solar Collectors for Process Heat: A Review,” International Journal of Research Publication and Reviews, vol. 2, no. 8, pp. 1402–1407, 2021, [Online]. Available: www.ijrpr.com
Downloads
Published
Issue
Section
License
Copyright (c) 2026 Fatima Hilal Abish, Abdulsalam D. M. Hassen
This work is licensed under a Creative Commons Attribution 4.0 International License.
