From: A review on solar water heating technology: Impacts of parameters and techno-economic studies
Author, (year) | Focus area | Observations/recommendations |
---|---|---|
Jaisankar et al. (2011) | Methodologies for thermal efficiency enhancement | More research should be carried out on thermosyphon SWH for performance enhancement |
Parallel flow should be considered | ||
Variable headers can be used for velocity stability in the HTF | ||
More research to minimize heat losses on a glazed cover | ||
Hossain et al. (2011) | SWH collector and flow channels | Experimental research lacking in the study of SWH flow channel |
Heat distribution can be improved by the use of a night insulation cover | ||
Shukla et al. (2013) | Progress in refrigerants | Refrigerants such as propane, NH3, and CO2 are under investigation for alleviation of environmental concerns |
Sadhishkumar and Balusamy (2014) | Heat transfer improvement and TES | Detailed research on the heat exchange behavior of solar collectors required |
The use of twisted tape in heat transfer is common but limited in application | ||
Wang and Yang (2014) | Loop heat pipe (LHP) for SWH application | Further development in the economic aspect and geometry are required in LHP for SWH application |
Studies under the standard test conditions are limited | ||
Halawa et al. (2015) | Thermal performance technique investigation in three countries—Australia, Taiwan, and Japan | Further investigation to explore a novel mechanism to ensure actual test condition is simulated |
Computer models for environmental check should be developed for future studies | ||
Jamar et al. (2016) | Collectors, Working fluids, and storage tank | Studies on the influence of nanoparticles at the base fluid of heat pipe of solar collectors are yet to be done |
Kannan and Vakeesan (2016) | Opportunities, prospects, and challenges | Economic, environmental, and social factors identified as barriers in the solar industry |
Gautam et al. (2017) | Technical enhancement and economic viability | The economic situation of SWH should have an important focus |
Thermosyphon-designed SWH research is limited | ||
Different refrigeration need to be explored for better results | ||
Kee et al. (2018) | PCM application | For SWH, PCM temperature range of 40 – 70°C is the best |
PCM incorporated directly into the storage tank gives the best heat retention hence more research in system design and optimization is paramount | ||
Storage tank design needs improvement and the use of different PCM requires further exploit | ||
Hohne et al. (2019) | SWH application in South Africa | Hybrid water heating system (heat pump, geothermal, gas-fired plants) promises high performance and should be studied |
Vengadesan and Senthil (2020) | Flat plat SWH. Heat transfer enhancement | Study of hybrid nanofluids (including heat transfer enhancing materials) is limited and needs more numerical research |
Numerical analysis of porous medium with varying material and nanofluids required | ||
Commercial use of nanofluids for the system is not economically viable | ||
Shamsul Azha et al. (2020) | Flat-plate type SWH. Heat transfer improvement | Heat distribution improvement using vibration approach on ETSC improves heat enhancement but is yet to be done on FPSC |
Future research to focus on the use of vibration method within infrasound acoustic range (f < 20 Hz) | ||
Wei et al. (2021) | Life cycle assessment (LCA) of SWH | The LCA of SWH shows the system is economically viable. However, installation requires complex techno-economic analysis |
Faisal Ahmed et al. (2021) | Advances in technology | Further studies on the techno-economic analysis are required |
Forced circulation technologies are common, and natural circulation needs to be considered | ||
A combination of solar and fossil-fuel-powered systems should be considered | ||
Mane and Kale (2021) | Design and performance parameters | Computer simulations on heat-resistant thermal barriers and complex geometries of collector designs such as triangular and pentagonal should be considered in future studies |
Auxiliary storage system separate from the storage tank needs to be considered | ||
Pandey et al. (2021) | Energy, exergy, exergoeconomic, and enviro economic method for PCM application | Effects of various additions such as nanoparticles, their dimensions, and concentrations as well as the types of PCM should be considered in future research |
Further numerical analysis needs to be considered in future work | ||
Sharma and Chauhan (2022) | Collectors, latent heat storage | Studies on the ETC type ICS-SWHS-LHS limited |
Further research on nano-enhanced PCMs required | ||
Comparative analysis of different configurations of SWH-LHS is needed for further understanding | ||
Pathak et al. (2023) | PCM application | Limited optimization research on nano- based PCM |
More experimental and numerical studies recommeded |