Abstract
The preeminent slope angle of solar panels is an important determinant of falling solar radiation on the surface of photovoltaic panels. Characteristics of the position of latitude, the sun, and local geography must be explained and understood to determine the slope angle correctly. This study presents a model built mathematically by using a Microsoft Excel spreadsheet to achieve the total monthly, seasonally and annual solar radiation on tilted photovoltaic panels in all provinces in Turkey. From NASA Prediction of Worldwide Energy Resources (power), horizontal solar radiation data were obtained for the purposes of calculating. Also, the best fixed tilt angle (β) was determined by finding the value of angle from 0° to 90° in steps of 1° for which the total maximum solar radiation on the photovoltaic surface was obtained. The study aims particularly at facilitating the installation of the pv panel after determining the best fixed tilt angle (β) to obtain the best solar radiation in the absence of meteorological data for all provinces in Turkey. This research is considered as a reference for any interested researcher. The results showed that the highest value of annual solar radiation occurs in the province of Aydin with 8027.55 Mj/m2 year and monthly optimum tilt angle is equal to 37.17°. On the other hand, the lowest amount of annual solar radiation occurs in the province of Artvin with 5586.74 Mj/m2 year and monthly optimum tilt angle is equal to 38.83°. As a result, the average annual fixed monthly optimum tilt angle in Turkey is equal to 38.14° with solar radiation about 6866.1136 Mj/m2year.
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Abbreviations
- G on :
-
Extraterrestrial radiation (w/m2)
- G sc :
-
Constant solar radiation \(\left( { = 1367\;{\text{w}}/{{\text{m}}^2}} \right)\;{\text{or}}\;\left( {\; = 4.92\frac{{{\text{mj}}}}{{{{\text{m}}^2}{\text{hr}}}}} \right)\)
- HG:
-
Global radiation (\({\text{Mj}}/{{\text{m}}^2}{\text{day}}\))
- \({H_b}\) :
-
Beam radiation (\({\text{Mj}}/{{\text{m}}^2}{\text{day}}\))
- \({H_d}\) :
-
Diffuse radiation (\({\text{Mj}}/{{\text{m}}^2}{\text{day}}\))
- \({H_o}\) :
-
Extraterrestrial radiation (\({\text{Mj}}/{{\text{m}}^2}{\text{day}}\))
- \({H_R}\) :
-
Reflected radiation from the ground
- \({n_{{\text{day}}}}\) :
-
The first day of the year
- R b :
-
The geometric factor (dimensionless)
- n :
-
Day of year
- ρ g :
-
Ground reflectance (dimensionless)
- K T :
-
The monthly average clearness index
- ST:
-
The solar time
- \(\beta\) :
-
Slope of the surface from horizontal (◦)
- \(\emptyset\) :
-
Latitude of site (◦)
- \(\gamma\) :
-
Surface azimuth angle (◦)
- δ :
-
Declination of the solar angle (◦)
- ω :
-
Solid (hour) angle (◦)
- ρ :
-
Density of reflectance (≈ 0.2)
- θ:
-
The angle of incidence radiation (◦)
- \({\omega_{{\text{ss}}}}\) :
-
Sunset hour angle (◦)
- \({\omega_{{\text{sr}}}}\) :
-
Sunrise hour angle (◦)
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Abed, F., Al-Salami, Q.H. Calculate the best slope angle of photovoltaic panels theoretically in all cities in Turkey. Int. J. Environ. Sci. Technol. 19, 9639–9654 (2022). https://doi.org/10.1007/s13762-021-03797-y
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DOI: https://doi.org/10.1007/s13762-021-03797-y