Computational Technology Resources - CCP

Keywords: solar radiation, clear sky, real-sky, shadows, adaptive meshes, solar power, solar photovoltaics, solar thermal.

Summary

A numerical model for generating solar radiation maps to be used for the evaluation of different power generation strategies is proposed. The solar radiation model is implemented taking into account the terrain surface with the use of two-dimensional adaptive meshes of triangles, which are made using a refinement-derefinement procedure in accordance with the variations of terrain surface, orography and albedo. As we will use the model to find the ideal location to obtain the maximum power generation, taking into account the effect of shadows for each time step is required. The solar radiation is first computed for clear-sky conditions, considering the different components of radiation, that is, beam, diffuse and reflected radiations.

The real-sky radiation is computed daily starting from the results of clear-sky radiation, in terms of the clear-sky index. The maps of clear-sky index are obtained from a spatial interpolation of observational data that are available for each day at several points of the zone under consideration. Finally, the solar radiation maps of a month are calculated from the daily results. Starting from the work of Suri and Hofierka [1], we have proposed both the use of adaptive meshes for surface discretization and a new method for detecting the shadows over each triangle of the surface [2]. Results have been improved by means of the use of a typical meteorological year (TMY) extracted from the available measurements stations data [3]. To obtain the radiation values in real sky conditions we use the TMY. Using radiation values from a single year would take us to a non reliable result so we need an accurate typical meteorological year which describes both, daily global solar irradiation and daily sunshine duration. The real trend of the global irradiation behaviour in every location is represented by the median TMY series.

Under clear sky conditions, beam, diffuse and reflected radiation values are around 85%, 15% and 0.5% of the mean global radiation respectively. The monthly daily average real sky global radiation, for the whole studied region, varies from 10.6 MJ/m² per day in December, to 25.6 MJ/m² per day in June.

This model permits the analysis of the generation possibilities from both, photovoltaic and solar thermal power and the suitability of different locations in Gran Canaria Island.

References

1: M. Suri, J. Hofierka, "A New GIS-based Solar Radiation Model and its application to photovoltaic assessments", Transactions in GIS, 8(2), 175-190, 2004. doi:10.1111/j.1467-9671.2004.00174.x
2: G. Montero, J.M. Escobar, E. Rodríguez, R. Montenegro, "Solar radiation and shadow modelling with adaptive triangular meshes", Solar Energy, 83(7), 998-1012, 2009. doi:10.1016/j.solener.2009.01.004
3: L. Mazorra, F. Díaz, P. Navarro, "Estimation of global solar radiation by means of sunshine duration", Proceedings of ISES Solar World Congress, Beijing, China, I-V, 2627-2631, 2007.

purchase the full-text of this paper (price £20)

go to the previous paper
go to the next paper
return to the table of contents
return to the book description
purchase this book (price £125 +P&P)

	Computational & Technology Resources an online resource for computational, engineering & technology publications
	not logged in - login
Front Page Browse CCP CSETS CTR IJRT Other Authors Search Purchase Guide FAQ Contact us	Civil-Comp Proceedings ISSN 1759-3433 CCP: 94 PROCEEDINGS OF THE SEVENTH INTERNATIONAL CONFERENCE ON ENGINEERING COMPUTATIONAL TECHNOLOGY Edited by: Paper 172 A Solar Radiation Model for Photovoltaic and Solar Thermal Power Exploitation F. Díaz, G. Montero, J.M. Escobar, E. Rodríguez and R. Montenegro University Institute for Intelligent Systems and Numerical Applications in Engineering, University of Las Palmas de Gran Canaria, Spain doi:10.4203/ccp.94.172 purchase the full-text of this paper Full Bibliographic Reference for this paper , "A Solar Radiation Model for Photovoltaic and Solar Thermal Power Exploitation", in , (Editors), "Proceedings of the Seventh International Conference on Engineering Computational Technology", Civil-Comp Press, Stirlingshire, UK, Paper 172, 2010. doi:10.4203/ccp.94.172 Keywords: solar radiation, clear sky, real-sky, shadows, adaptive meshes, solar power, solar photovoltaics, solar thermal. Summary A numerical model for generating solar radiation maps to be used for the evaluation of different power generation strategies is proposed. The solar radiation model is implemented taking into account the terrain surface with the use of two-dimensional adaptive meshes of triangles, which are made using a refinement-derefinement procedure in accordance with the variations of terrain surface, orography and albedo. As we will use the model to find the ideal location to obtain the maximum power generation, taking into account the effect of shadows for each time step is required. The solar radiation is first computed for clear-sky conditions, considering the different components of radiation, that is, beam, diffuse and reflected radiations. The real-sky radiation is computed daily starting from the results of clear-sky radiation, in terms of the clear-sky index. The maps of clear-sky index are obtained from a spatial interpolation of observational data that are available for each day at several points of the zone under consideration. Finally, the solar radiation maps of a month are calculated from the daily results. Starting from the work of Suri and Hofierka [1], we have proposed both the use of adaptive meshes for surface discretization and a new method for detecting the shadows over each triangle of the surface [2]. Results have been improved by means of the use of a typical meteorological year (TMY) extracted from the available measurements stations data [3]. To obtain the radiation values in real sky conditions we use the TMY. Using radiation values from a single year would take us to a non reliable result so we need an accurate typical meteorological year which describes both, daily global solar irradiation and daily sunshine duration. The real trend of the global irradiation behaviour in every location is represented by the median TMY series. Under clear sky conditions, beam, diffuse and reflected radiation values are around 85%, 15% and 0.5% of the mean global radiation respectively. The monthly daily average real sky global radiation, for the whole studied region, varies from 10.6 MJ/m² per day in December, to 25.6 MJ/m² per day in June. This model permits the analysis of the generation possibilities from both, photovoltaic and solar thermal power and the suitability of different locations in Gran Canaria Island. References 1 M. Suri, J. Hofierka, "A New GIS-based Solar Radiation Model and its application to photovoltaic assessments", Transactions in GIS, 8(2), 175-190, 2004. doi:10.1111/j.1467-9671.2004.00174.x 2 G. Montero, J.M. Escobar, E. Rodríguez, R. Montenegro, "Solar radiation and shadow modelling with adaptive triangular meshes", Solar Energy, 83(7), 998-1012, 2009. doi:10.1016/j.solener.2009.01.004 3 L. Mazorra, F. Díaz, P. Navarro, "Estimation of global solar radiation by means of sunshine duration", Proceedings of ISES Solar World Congress, Beijing, China, I-V, 2627-2631, 2007. purchase the full-text of this paper (price £20) go to the previous paper go to the next paper return to the table of contents return to the book description purchase this book (price £125 +P&P)
Back to top	©Civil-Comp Limited 2023 - terms & conditions