Experimental comparison of erythritol and erythritol-granite pebble mixtures as heat storage materials for solar cooking – Green Technology & Innovation | Caravel Press
In this article, a comparison is presented between a pure latent heat storage system (erythritol) and a mixed storage system consisting of equal mass ratios of erythritol and granite pebbles (5 – 10 mm) for a solar cooking application. Two small black stainless cooking pots with a capacity of 1 L were placed inside two larger 5 L cooking pots to form simple storage cooking pots. The space between the pots was filled with thermal energy storage (TES) material. In the first configuration, the space between the pots was filled with 2 kg of erythritol. In the second configuration, the storage system consisted of 1 kg of erythritol and 1 kg of granite pebbles in the same space. The first experimental tests involved charging the storage cooking pots without any load for 4 h, followed by discharging them using heating loads in insulated wonder bags to evaluate off-sunshine cooking performance for another 4 h. The second experimental test involved simultaneous cooking and heat storage alternating between charging and discharging cycles. Experimental results showed that the mixed storage system achieved higher temperatures than the erythritol storage system during charging without cooking. During discharging cycles, the heat utilization rate was faster for the mixed storage system than for the erythritol storage system. Both storage systems enabled the cooking of multiple meals within an 8-h cooking period. However, at the end of the experiments, the erythritol storage system retained higher temperatures than the mixed storage system. Future work will focus on characterizing the thermophysical properties of the mixed storage system, optimizing the erythritol-to-granite mixing ratio for improved thermal performance, and investigating alternative, locally available TES materials – such as sandstone, marble, limestone, and xylitol – for potential use in mixed storage systems.
Keywords. Erythritol; Granite; Heat storage materials; Solar cooking
References
Aramesh M, Ghalebani M, Kasaeian A, et al. A review of recent advances in solar cooking technology. Renew Energy. 2019;140:419-435. doi: 10.1016/j.renene.2019.03.021
Lentswe K, Mawire A, Owusu P, Shobo A. A review of parabolic solar cookers with thermal energy storage. Heliyon. 2021;7(10):e08226. doi: 10.1016/j.heliyon.2021.e08226
Coccia G, Aquilanti A, Tomassetti S, Comodi G, Di Nicola G. Design, realisation, and tests of a portable solar box cooker coupled with an erythritol-based PCM thermal energy storage. Solar Energy. 2020;201:530-540. doi: 10.1016/j.solener.2020.03.031
Anilkumar BC, Maniyeri R, Anish S. Optimum selection of phase change material for solar box cooker integrated with thermal energy storage unit using multi-criteria decision- making technique. J Energy Storage. 2021;40:102807. doi: 10.1016/j.est.2021.102807
Goyal RK, Eswaramoorthy M. Theoretical and experimental analysis of box-type solar cooker with sensible heat storage. Solar Energy. 2024;268:112273. doi: 10.1016/j.solener.2023.112273
El Moussaoui N, Talbi S, Atmane I, et al. Feasibility of a new design of a parabolic trough solar thermal cooker (PSTC). Solar Energy. 2020;201:866-871. doi: 10.1016/j.solener.2020.03.079
Tawfik MA, Sagade AA, Palma-Behnke R, Abd Allah WE, Hanan ME. Performance evaluation of solar cooker with tracking type bottom reflector retrofitted with a novel design of thermal storage incorporated absorber plate. J Energy Storage. 2022;51:104432. doi: 10.1016/j.est.2022.104432
Getnet MY, Gunjo DG, Sinha DK. Experimental investigation of thermal storage integrated indirect solar cooker with and without reflectors. Results Eng. 2023;18:101022. doi: 10.1016/j.rineng.2023.101022
Khatri R, Goyal R, Sharma RV. Comparative experimental investigations on a low-cost solar cooker with energy storage materials for sustainable development. Results Eng. 2023;20:101546. doi: 10.1016/j.rineng.2023.101546
Bhave AG, Kale CK. Development of a thermal storage type solar cooker for high temperature cooking using solar salt. Solar Energy Mater Solar Cells. 2020;208:110394. doi: 10.1016/j.solmat.2020.110394
Senthil R. Enhancement of productivity of parabolic dish solar cooker using integrated phase change material. Mater Today Proc. 2021;34:386-388. doi: 10.1016/j.matpr.2020.02.197
Mekonnen BA, Liyew KW, Tigabu MT. Solar cooking in Ethiopia: Experimental testing and performance evaluation of SK14 solar cooker. Case Stud Thermal Eng. 2020;22:100766. doi: 10.1016/j.csite.2020.100766
Gorjian A, Rahmati E, Gorjian S, Anand A, Jathar LD. A comprehensive study of research and development in concentrating solar cookers (CSCs): Design considerations, recent advancements, and economics. Solar Energy. 2022;245:80-107. doi: 10.1016/j.solener.2022.08.066
Bhave AG, Thakare KA. Development of a solar thermal storage cum cooking device using salt hydrate. Solar Energy. 2018;171:784-789. doi: 10.1016/j.solener.2018.07.018
Abedigamba OP, Mndeme FS, Mawire A, Bahadur I. Thermo- physical properties and thermal energy storage performance of two vegetable oils. J Energy Storage. 2023;61:106774. doi: 10.1016/j.est.2023.106774
Shaikh M, Uzair M, Raza SA. Optimization of thermal storage using different materials for cooking with solar power. Trans Canad Soc Mech Eng. 2021;46:490-502. doi: 10.1139/tcsme-2021-0160
Mawire A, Lentswe K, Owusu P, et al. Performance comparison of two solar cooking storage pots combined with wonderbag slow cookers for off-sunshine cooking. Solar Energy. 2020;208:1166-1180. doi: 10.1016/j.solener.2020.08.053
Mullick S, Kandpal T, Saxena A. Thermal test procedure for box-type solar cookers. Solar Energy. 1987;39:353-360. doi: 10.1016/S0038-092X(87)80021-X
Verma S, Banerjee S, Das R. A fully analytical model of a box solar cooker with sensible thermal storage. Solar Energy. 2022;233:531-542. doi: 10.1016/j.solener.2021.12.035
Dev A, Amatya S, Dumre Y, Shah M, Baral B. Exploring aluminum as a solid thermal storage medium for solar cooking application: An experimental investigation coupled with numerical modeling using OpenFOAM. Heliyon. 2024;10(21):e39855. doi: 10.1016/j.heliyon.2024.e39855
Osei M, Staveland O, McGowan S, et al. Phase change thermal storage: Cooking with more power and versatility. Solar Energy. 2021;220:1065-1073. doi: 10.1016/j.solener.2021.03.040
Yadav V, Yadav A. Experimental investigation of novel design of solar cooker with dual thermal storage unit based on parabolic dish-type collector. Int J Energy Clean Environ. 2013;14:295-310. doi: 10.1615/InterJEnerCleanEnv.2015011429
Yadav V, Kumar Y, Agrawal H, Yadav A. Thermal performance evaluation of solar cooker with latent and sensible heat storage unit for evening cooking. Aust J Mech Eng. 2017;15:93-102. doi: 10.1080/14484846.2015.1093260
Mawire A, Lentswe K, Owusu P. Performance of two solar cooking storage pots using parabolic dish solar concentrators during solar and storage cooking periods with different heating loads. Results Eng. 2022;13:100336. doi: 10.1016/j.rineng.2022.100336
Li B, Ju F. Thermal stability of granite for high-temperature thermal energy storage in concentrating solar power plants. Appl Energy. 2018;138:409-416. doi: 10.1016/j.applthermaleng.2018.04.071
Lugolole R, Mawire A, Lentswe KA, Okello D, Nyeinga K. Thermal performance comparison of three sensible heat thermal energy storage systems during charging cycles. Sustain Energy Technol Assess. 2018;30:37-51. doi: 10.1016/j.seta.2018.09.002
Lugolole R, Mawire A, Okello D, Lentswe KA, Nyeinga K, Shobo AB. Experimental analyses of sensible heat thermal energy storage systems during discharging. Sustain Energy Technol Assess. 2019;35:117-130. doi: 10.1016/j.seta.2019.06.007
Saxena A, Joshi SK, Gupta P, Tirth V, Suryavanshi A, Singh DB, Sethi M. An experimental comparative analysis of the appropriateness of different sensible heat storage materials for solar cooking. J Energy Storage. 2023;61:106761. doi: 10.1016/j.est.2023.106761
Zhang S, Li Y, Yan Y. Hybrid sensible-latent heat thermal energy storage using natural stones to enhance heat transfer: Energy, exergy, and economic analysis. Energy. 2024;286:129530. doi: 10.1016/j.energy.2023.129530
Cho WJ, Kwon S, Choi JW. The thermal conductivity of granite with various water contents. Eng Geol. 2009;107:167-171. doi: 10.1016/j.enggeo.2009.05.012
R.S. Online. Sefram DAS 240 Multipurpose Data Logger, Ethernet, USB; 2024. Available from: https://za.rs-online. com/web/p/data-loggers/1259517?gb=s [Last accessed on 2025 Jan 14].
Campbell Scientific. CMP11 Pyranometer; 2024. Available from: https://www.campbellsci.co.za/cmp11 [Last accessed on Jan 14].
Takealot. Erythritol Price; 2025. Available from: https://www.takealot.com/sweet-nothings-erythritol-600g-sweetener/PLID71884468 [Last accessed on 2025 Jan 14].
Builders. Granite Price; 2025. Available from: https://www.buildersmerchant.co.za/collections/gravel-aggregates-supplier-dolomite-granite-silica-quartz/products/13mm-crushed-stone-aggregate-4-ton-pink?variant=31836271968336 [Last accessed on 2025 Jan 14].
How to cite this article
Mawire, A. and Abedigamba, O.P. (2025). 'Experimental comparison of erythritol and erythritol-granite pebble mixtures as heat storage materials for solar cooking'. Green Technology & Innovation, 1, pp. 1-12. https://doi.org/10.36922/gti.6191