Abstract
In this paper, the solar radiation on diversely oriented surfaces and optimum tilts for solar absorbers were assessed. The KT solar radiation model was coded in the MATLAB-based environment to compute the monthly solar radiation values. Seven-year data of monthly average daily solar radiation on a horizontal surface in Bangi, Malaysia (latitude = 3°N) were adopted as input in the simulation programme and the results were compared with the local optimum tilt angle at solar noon and other solar radiation model. The contour mappings of solar irradiation at various orientations in 12 months were presented. Results showed that the surface tilted ≤20° could intercept a relatively high solar intensity, which was less sensitive to the variation of azimuths with average solar insolation deviation of 11.82 %. The monthly optimum tilt angle altered throughout the year, ranging from −24° (in equator direction) to +22° (in north direction). The estimated annual optimum slope, 1.4° facing to the equator, was close to local latitude. Based on the seasonal analysis, the north-facing surface was able to intercept higher daily average solar radiation energy compared to south-facing plane. The optimum angles for seasonal south- and north-facing surfaces were found to be 14.4° and 14.8°, respectively, with a tolerable slope deviation of ±5° from the optimal values in the present work.
Highlights
Solar energy is typically acknowledged as an important renewable energy source for the future in many countries
To maximise the interception of incident solar radiation energy, a solar absorber unit is positioned at the right orientation, which can be described in tilt and azimuth angles
A study of optimum tilt angle for solar collectors in Iran was carried out using an empirical approach and the results showed that the optimum tilt angle was lower for a place with a low clearness index despite the same latitude [17]
Summary
Solar energy is typically acknowledged as an important renewable energy source for the future in many countries. A study by El-Sebaii et al [15] indicated the isotropic model could provide a good estimate of horizontal diffuse radiation in Jeddah They suggested the optimum slope to be latitude þ15° for winter season and latitude À15° for summer season. The monthly average daily global radiations on surfaces at various azimuth and tilt angles throughout 1 year were analysed for Bangi, Malaysia (located at latitude of 3°N). The model was chosen as it enabled the determination of solar irradiation for all surface orientations with good estimation This method is appropriate for an interested location where the H is the only available solar radiation data at the site. The solar insolation at various orientations under the Malaysian tropical climates was assessed to serve as a reference for the solar application in buildings
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callMore From: International Journal of Energy and Environmental Engineering
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
