A PV system is to be installed on a flat roof in Naples (Italy). The area of the roof that can be utilized for installing the PV system is 12x13 [m2] . The roof is oriented such that the sides are parallel to the East-West and North-South directions, respectively.
The owner of the roof decides to use PV modules with dimensions of 1.65 [m] × 0.99 [m] × 0.040 [m] . He is interested in the following configuration:
The modules are mounted under a tilt of 30° facing south. The short side of the modules is touching the ground. Shading calculations showed that the distance between the short edges of each row of modules has to be 4.05 [m]
How many modules can be mounted on the roof in this configuration? Assume for this calculation that the thickness of the modules is 0 [mm] instead of 40 [mm] .
A)14
B)21
C)24
D)36
well, the shadow cast by each panel is 0.99 x 1.65cos30° = 0.99 x 1.43 m
Since the rows have to be 4.05m apart, n rows need 0.99n + 4.05*(n-1) m
So, figure out how many panels fit along each direction, and just multiply as usual.
actually i don't understand your solution. pls clear...what mult i have to do....
To determine the number of modules that can be mounted on the roof in this configuration, we need to calculate the area covered by a single module and then divide the total roof area by the area covered by each module.
1. Calculate the area covered by a single module:
The dimensions of the module are given as:
Length = 1.65 [m]
Width = 0.99 [m]
Area = Length × Width = 1.65 [m] × 0.99 [m] = 1.6335 [m²]
2. Calculate the effective area covered by a single module at the given tilt angle of 30°:
The tilt angle reduces the effective area covered by the module. The effective area can be calculated by multiplying the area of the module by the cosine of the tilt angle.
Effective Area = Area × cos(tilt angle)
Tilt angle = 30° = 0.5236 [radians]
Effective Area = 1.6335 [m²] × cos(0.5236) = 1.6335 [m²] × 0.8660 = 1.4148 [m²]
3. Calculate the number of modules that can be mounted on the roof:
The given roof area is 12 [m] × 13 [m] = 156 [m²]
Number of Modules = Roof Area / Effective Area
Number of Modules = 156 [m²] / 1.4148 [m²] ≈ 110.115
Since we cannot have a fractional number of modules, we should round down to the nearest whole number to obtain the maximum number of modules that can be mounted.
Number of Modules = 110
4. Account for the spacing between rows:
The shading calculations showed that the distance between the short edges of each row of modules should be 4.05 [m].
In this configuration, the short side of the modules is touching the ground, so the 4.05 [m] spacing refers to the distance between the rows of modules.
To calculate the number of modules in each row, we need to subtract the spacing between rows from the roof width and divide by the width of each module.
Number of Modules in Each Row = (Roof Width - Spacing) / Module Width
Roof Width = 13 [m]
Spacing = 4.05 [m]
Module Width = 0.99 [m]
Number of Modules in Each Row = (13 [m] - 4.05 [m]) / 0.99 [m] ≈ 8.939
Again, we need to round down to the nearest whole number.
Number of Modules in Each Row = 8
5. Calculate the total number of modules:
To find the total number of modules, we multiply the number of modules in each row by the number of rows.
Total Number of Modules = Number of Modules in Each Row × Number of Rows
Number of Modules in Each Row = 8
Number of Rows = 110 / 8 = 13.75
We round down the number of rows to the nearest whole number.
Number of Rows = 13
Total Number of Modules = 8 × 13 = 104
Therefore, the maximum number of modules that can be mounted on the roof in this configuration is approximately 104. However, the given options (A, B, C, D) do not include this exact value. It's possible that there is additional information or a mistake in the given options.