THERMAL PERFORMANCE OF SOLAR ENERGY STORAGE IN SOME SOLID MATERIALS

Gamea, G. R.; Taha, A. T.; Keshek, M. H.

doi:10.21608/mjae.2012.102624

THERMAL PERFORMANCE OF SOLAR ENERGY STORAGE IN SOME SOLID MATERIALS

Document Type : Original Article

Authors

¹ Assoc Prof. of Agric. Eng. Dep., Fac. of Agr., Min. Univ., Egypt.

² Lect. of Agric. Eng. Dep., Fac. of Agr., Min. Univ., Egypt.

³ Ass lect. of Agric. Eng. Dep., Fac. of Agr., Min. Univ., Egypt.

10.21608/mjae.2012.102624

Abstract

The study carried out, to study thermal performance of some solid as storage units. Three similar storage units were designed, manufactured and evaluated in Agricultural Engineering Department, Faculty of Agricultural, Minoufiya University. Three types of granulates are Basalt, Sand and Gravel were used to store solar energy during the day, at three thicknesses (20, 40 and 60 cm). The all experiments carried out with closed units during daylight and opened in the night. The all experiments repeated with opened units during daylight and night. Thermal performance was evaluated by, hourly energy stored, daily energy stored (KJ/ kg), storage thermal efficiency, and characteristics of passing air through storage units.
Basalt gave the best results in with all condition, the amount of hourly heat stored at Basalt at thickness 60 cm.
The daily amount of heat (kJ/kg) stored in storage materials at thickness 20 cm was higher than at thicknesses 40 and 60 cm.
The daily amount of heat stored in the Basalt was 23.98, 12.88 and 8.89 kJ / kg at the thickness of 20, 40, 60 cm, respectively, when the storage units are closed during daylight. And by 5.64, 3.29 and 2.92 kJ / kg at the thickness of 20, 40, 60 cm, respectively, when the storage units are open during daylight.
The mean storage efficiency for storage materials at thickness 60 cm was higher than at thicknesses 40 and 20 cm.
The difference in air temperature at the entry and exit from the storage units was higher in the case of air passing through storage unit at 20 cm by 54.61, 77 % than its at thicknesses were 40, 60 cm, respectively, when the storage units are closed during the daylight and opened during night.

Main Subjects

Agricultural Constructions Engineering

References

Abdellatif, S. M., (1985) "Solar energy collection, storage and utilization in protected cropping". Ph. D. Wye College, University of London, UK.

Bal, M.L.; S. Satya.; and S.N. Naik., (2010) " Solar dryer with thermal energy storage systems for drying agricultural food products: A review". Renewable and Sustainable Energy Reviews, 14.; 2298–2314.

Dincer, I. and S. Dost., (1996) "A perspective on thermal energy storage systems for solar energy applications". International journal of energy research, vol. 20,547-557.

Dincer, I. and A. M. Rosen., (2010) thermal energy storage systems and applications, John Wiley & Sons, Ltd. United Kingdom.

Duansheng, C.; L. Buzhou.; N. Hemin.; Z. Haishan.; Z. Jiangou.; and T. Quan (1991) "Technology of the energy – saving sunlight greenhouses in China". The proceeding of International Symposium on Applied Technology of Greenhouse, pp:41-49.

Duffie, J. A. and Beckman, W. R., (2006) "Solar Engineering for Thermal Processes". 3^rd ed., pp. 907. John Wiley and Sons. New York: USA.

El-Kassaby, M. M.; and A. A. Ghoneim., (1993) "Comparison of measured and predicted performance of different heat storage systems". Renewable Energy;3(8):849–56.

El-Sebaii A.A .; S. Aboul-Enein.; M.R.I. Ramadan.; and E. El-Bialy., (2007)" Year round performance of double pass solar air heater with packed bed". Energy Conversion and Management 48 .; 990–1003.

Gil, A., M. Medrano., I. Martorell ., A. L. Zaro., P. Dolado., B. Zalba., and L. F. Cabeza (2010) "State of the art on high temperature thermal energy storage for power generation. Part 1—Concepts, materials and modellization" . Renewable and Sustainable Energy Reviews 14 .; 31–55.

Hamdan, M. A., (1998) "Investigation of an inexpensive solar collector storage system". Energy Convers Manage;39(5–6):415–20.

Johnson, R. W.; (1992) "Analytical results for specific system. Passive solar buildings. The MIT Pres, Cambridge, Massachusets, London.

Karlekar, B. V.; and R. M. Desmond., (1982). "Engineering Heat Transfer". USA: West Publishing Company.

Mohamed M. A., G. R. Gamea and M. H. Keshek., (2010) "Drying characteristics of okra by different solar dryers". Misr J. Ag. Eng. Vol. 27( 1) :294 – 312.

Ozturk H. H.; and A. Bascetincelik., (2003) "Energy and exergy efficiency of a packed bed heat storage unit for greenhouse heating". Biosyst Eng;86(2):231–45.

Somerton., H.W., (1992) Thermal Properties and Temperature-Related Behavior of Rock/Fluid Systems. Elsevier Publishing Company.