SOLAR SYSTEM WITH SEASONAL THERMAL ENERGY STORAGE

The paper presents the results of the development of a methodology for a comprehensive assessment of the system's efficiency, which includes solar collectors, a heat storage tank, a ground heat accumulator, and a building heating system. The model of non-stationary heat exchange makes it possible to determine the area and the number of solar collectors and the volume of a seasonal (ground) heat accumulator for various climatic conditions, types of solar engineering equipment, types of heating systems in the building, providing the necessary temperature characteristics of the building. We have obtained analytical expressions for a seasonal change in solar radiation and ambient temperatures typical for a sharply continental climate, and have made a numerical study of the time of use of the accumulated energy for a building with a heated area of 70 m² . For a 500 m³ ground heat accumulator with a maximum heating temperature (90 °C), the stored energy is shown to be sufficient for heating the building with a warm floor system for more than 100 days. The paper submits the data confirming expediency of use of solar systems of heat supply with the ground heat accumulator for the severe climatic conditions characteristic of the Ural region of Russia. The use of ground heat accumulators is a simple and low-cost method of transferring solar energy in time (from summer to winter), which allows us to significantly reduce the cost of organic fuel for heating the premises during the heating season. The greatest efficiency of use of the energy accumulated in the ground is achieved when applying low temperature heating systems (underfloor heating, air heating). This technique is quite universal and can be used for any grounds and accumulative environments that differ from the natural ground by thermal physical characteristics (talcochlorite, talcomagnesite, salt compositions, etc.), as well as for other types of thermal loads, such as maintaining a favorable temperature regime in swimming pools and agricultural structures of enclosed soil.

1. Kuravi S., Trahan J., Goswami D.Y., Rahman M.M., Stefanakos E.K. Thermal energy storage technologies and systems for concentrating solar power plants. Progress in Energy and Combustion Science, 2013;39(4):285–319.

2. Zhang H., Baeyens J., Cáceres G., Degrève J., Lv Y. Thermal energy storage: Recent developments and practical aspects. Progress in Energy and Combustion Science, 2016;53:1–40.

3. Tian Y., Zhao C.Y. A review of solar collectors and thermal energy storage in solar thermal applications. Applied Energy, 2013;104:538–553.

4. Long Liu, Neng Zhu, Jing Zhao. Thermal equilibrium research of solar seasonal storage system coupling with ground-source heat pump. Energy, 2016;99:83–90.

5. Kharchenko N.V. Individual solar installation (Individual'nye solnechnye ustanovki). Moscow: Energoatomizdat Publ., 1991 (in Russ.).

6. Guruprasad Alva, Yaxue Lin, Guiyin Fang. An overview of thermal energy storage systems. Energy, 2018;144:341–378.

7. Xu J., Wang R.Z., Li Y. An overview of thermal energy storage systems. Sol. Energy, 2014;103:610–638.

8. Guruprasad Alva, Lingkun Liu, Xiang Huang, Guiyin Fang. Thermal energy storage materials and systems for solar energy applications. Renewable and Sustainable Energy Reviews, 2017;68(1):693–706.

9. Bauer D., Marx R., Nußbicker-Lux J., Ochs F., Heidemann W., Mu¨ller-Steinhagen H. German central solar heating plants with seasonal heat storage. Sol. Energy, 2010;84:612–623.

10. Benli H., Durmus A. Performance analysis of a latent heat storage system with phase change material for new designed solar collectors in greenhouse heating. Sol. Energy, 2009;83:2109–2119.

11. Benli, H., Energetic performance analysis of a ground-source heat pump system with latent heat storage for a greenhouse heating. Energy Convers. Manage, 2011;52:581–589.

12. Berroug F., Lakhal E.K., El Omari M., Faraji M., El Qarnia H. Thermal performance of a greenhouse with a phase change material north wall. Energy Build, 2011;43:3027–3035.

13. Paiho S., Hoang H., Hukkalainen M. Energy and emission analyses of solar assisted local energy solutions with seasonal heat storage in a Finnish case district. Renewable Energy, 2017;107:147–155.

14. Wang X., Zheng M., Zhang W., Zhang S., Yang T. Experimental study of a solar-assisted ground-coupled heat pump system with solar seasonal thermal storage in severe cold areas. Energy and Buildings, 2010;42(11)2104–2110.

15. Zalba B., Cabeza L.F., Mehling H. Review on thermal energy storage with phase change: materials, heat transfer analysis and applications. Applied Thermal Engineering, 2003;23(3):251–283.

16. Sharma A., Tyagi V.V., Chen C.R., Buddhi D. Review on thermal energy storage with phase change materials and applications. Renewable and Sustainable Energy Reviews, 2009;13(2):318–345.

17. Anisimov A. Energy-efficient heating appliances from Karelia (thermal receivers). (Energosberegayushchie otopitel'nye pribory iz Karelii (teploakkumulyatory). International Scientific Journal for Alternative Energy and Ecology (ISJAEE), 2004;5(10)44–46 (in Russ.).

18. Vysochin V.V. Mathematical model of solar collectors with seasonal heat accumulator (Matematicheskaya model' geliosistemy s sezonnym akkumulyatorom tepla). Trudy Odesskogo politekhnicheskogo universiteta, 2011;2(36)125–129 (in Russ.).

19. Vysochin V.V. Influence of seasonal heat battery sizes at the battery life of the solar system (Vliyanie razmerov sezonnogo akkumulyatora tepla na avtonomnost' raboty geliosistemy). Trudy Odesskogo politekhnicheskogo universiteta, 2012;1(36)129–132 (in Russ.).

20. Beckmann G., Gilli P. Thermal energy storage (Teplovoye akkumulirovaniye energii). Moscow: Mir Publ., 1987 (in Russ.).

21. Kroll J.A., Ziegler F. The use of ground heat storages and evacuated tube solar collectors for meeting the annual heating demand of family-sized houses. Sol. Energy, 2011;85(11):2611–2621.

22. Scientific-applied climate guide USSR // 3 perennial data series, parts 1–6, no. 9 Perm, Sverdlovsk, Chelyabinsk, Kurgan region, Bashkir Autonomous Soviet Socialist Republic (Nauchno-prikladnoi spravochnik po klimatu SSSR // seriya 3 mnogoletnie dannye: Permskaya, Sverdlovskaya, Chelyabinskaya, Kurganskaya oblasti, Bashkirskaya ASSR), Leningrad: Gidrometeoizdat Publ., 1990 (in Russ.).

23. Pekhovich A.I. Thermal calculation of solids (Raschet teplovogo rezhima tverdykh tel). Leningrad: Energiya Publ., 1976 (in Russ.).

24. Nemś M., Kasperski J., Nemś A., Bać A. Validation of a new concept of a solar air heating system with a long-term granite storage bed for a single-family house. Applied Energy, 2018;215:384–395.

25. Reyes A., Negrete D., Mahn A., Sepúlveda F. Design and evaluation of a heat exchanger that uses paraffin wax and recycled materials as solar energyaccumulator. Energy Conversion and Management, 2014;88:391–398.