SOLAR CANOPY SYSTEM
A solar canopy has a solar panel assembly including a first solar panel coupled to a second solar panel and oriented non-parallel with respect to the second solar panel. The solar panel assembly has an effective solar-panel-assembly wind loading less than a sum of a first-solar-panel effective wind loading and a second-solar-panel effective wind loading determined individually. An actual load applied by the solar panel assembly to a solar-panel-assembly support structure coupled thereto when the solar panel assembly is subject to a wind loading is less than a design load for the solar panel assembly subject to the wind loading based on a sum of a first-solar-panel net pressure and a second-solar-panel net pressure determined independently.
1 . A method for decreasing a maximum load on a solar canopy support structure, comprising:
disposing two or more photovoltaic modules on a support structure;
arranging a first photovoltaic module at a first non-parallel orientation relative to the support structure, the first photovoltaic module and the support structure forming a first angle; and
arranging a second photovoltaic module at a second non-parallel orientation relative to the support structure, the second photovoltaic module and the support structure forming a second angle; and
wherein a calculated maximum load for the support structure is less than a design maximum load for the support structure.
2 . The method of claim 1 , wherein the first photovoltaic module is tilted in a counter-clockwise direction and the second photovoltaic module is tilted in a clockwise direction.
3 . The method of claim 2 , further comprising:
arranging a third photovoltaic module at a third non-parallel orientation relative to the support structure.
4 . The method of claim 3 , wherein the third photovoltaic module is tilted parallel to the first photovoltaic module.
5 . The method of claim 3 , wherein the first photovoltaic module, the second photovoltaic module, and the third photovoltaic module are fixed at their non-parallel orientations.
6 . The method of claim 1 , wherein a plurality of purlins extend substantially vertically between a cross beam and the first photovoltaic module and between the cross beam and the second photovoltaic module and varying in length to achieve a desired tilt of the first photovoltaic module and the second photovoltaic module.
7 . The method of claim 1 , wherein the design maximum load is determined from a standard reference manual.
8 . The method of claim 1 , wherein the calculated maximum load for the support structure is determined by a force coefficient GC P , a first moment coefficient GC MHy , and a second moment coefficient GC My defined by the following equations:
G
C
P
=
F
normal
q
H
·
A
G
C
MHy
=
M
top
_
of
_
post
q
H
·
A
·
L
G
C
My
=
M
grade
q
H
·
A
·
L
where,
F normal is a force normal to a top surface of the first photovoltaic module or the second photovoltaic module;
M top_of_post is a moment about a top of a post (center of a cross beam);
M grade is a moment about a bottom of the post;
q H is a velocity pressure at a height (H) of ≤4.5 m in an open terrain;
A is an averaging area (Number of photovoltaic modules multiplied by 2 m 2 ); and
L is a nominal chord length, and
wherein the force coefficient GC P , the first moment coefficient GC MHy , and the second moment coefficient GC My are calculated from wind tunnel pressure data obtained by simultaneously measuring a pressure at a plurality of pressure taps embedded in a surface of the first photovoltaic modules and the second photovoltaic module.
9 . A method for calculating a reduced maximum load on a solar panel support structure, the method comprising:
arranging a first solar panel at a first angle relative to the solar panel support structure, wherein the first solar panel is at a first non-parallel orientation to the solar panel support structure;
arranging a second solar panel at a second angle relative to the solar panel support structure, wherein the second solar panel is at a second non-parallel orientation to the solar panel support structure;
analyzing the solar panel support structure, the first solar panel, and the second solar panel in a wind tunnel; and
collecting wind tunnel pressure data by simultaneously measuring a pressure at a plurality of pressure taps embedded in a surface of the first solar panel and a surface of the second solar panel; and
calculating the reduced maximum load using the wind tunnel pressure data.
10 . The method of claim 9 , wherein the reduced maximum load for the solar panel support structure is determined by a force coefficient GC P , a first moment coefficient GC MHy , and a second moment coefficient GC My defined by the following equations:
G
C
P
=
F
normal
q
H
·
A
G
C
MHy
=
M
top
_
of
_
post
q
H
·
A
·
L
G
C
My
=
M
grade
q
H
·
A
·
L
where,
F normal is a force normal to a top surface of the first solar panel or the second solar panel;
M top_of_post is a moment about a top of a post (center of a cross beam);
M grade is a moment about a bottom of the post;
q H is a velocity pressure at a height (H) of ≤4.5 m in an open terrain;
A is an averaging area (Number of solar panels multiplied by 2 m 2 ); and
L is a nominal chord length, and
wherein the force coefficient GC P , the first moment coefficient GC MHy , and the second moment coefficient GC My are calculated using the wind tunnel pressure data.
11 . The method of claim 9 , wherein the first solar panel is tilted in a counter-clockwise direction and the second solar panel is tilted in a clockwise direction.
12 . The method of claim 11 , wherein the first solar panel and the second solar panel are fixed at their non-parallel orientations.
13 . A solar panel assembly support structure, comprising:
a post having a post bottom end and a post top end opposite the post bottom end;
a cross beam attached to and supported by the post top end; and
a plurality of purlins extending between the cross beam and a first solar panel and between the cross beam and a second solar panel;
wherein the first solar panel has a first non-parallel orientation to the plurality of purlins;
wherein the second solar panel has a second non-parallel orientation to the plurality of purlins;
wherein the first non-parallel orientation is at an oblique angle to the second non-parallel orientation; and
wherein a calculated maximum load for the solar panel assembly support structure is less than a standard design maximum load for a standard solar panel assembly support structure, wherein the standard solar panel assembly support structure supports a plurality of solar panels with a parallel orientation to a standard plurality of support purlins of the standard solar panel assembly support structure.
14 . The solar panel assembly support structure of claim 13 , wherein the first solar panel is tilted in a counter-clockwise direction and the second solar panel is tilted in a clockwise direction.
15 . The solar panel assembly support structure of claim 14 , further comprising:
arranging a third solar panel at a third non-parallel orientation to the plurality of purlins.
16 . The solar panel assembly support structure of claim 15 , wherein the third solar panel is tilted parallel to the first solar panel.
17 . The solar panel assembly support structure of claim 15 , wherein the first solar panel, the second solar panel, and the third solar panel are fixed at their non-parallel orientations.
18 . The solar panel assembly support structure of claim 13 , wherein the plurality of purlins vary in length to achieve a desired tilt of the first solar panel and the second solar panel.
19 . The solar panel assembly support structure of claim 13 , wherein the standard design maximum load is determined from a standard reference manual.
20 . The solar panel assembly support structure of claim 13 , wherein the calculated maximum load for the solar panel assembly support structure is determined by a force coefficient GC P , a first moment coefficient GCM My , and a second moment coefficient GC My defined by the following equations:
G
C
P
=
F
normal
q
H
·
A
G
C
MHy
=
M
top
_
of
_
post
q
H
·
A
·
L
G
C
My
=
M
grade
q
H
·
A
·
L
where,
F normal is a force normal to a top surface of the first solar panel or the second solar panel;
M top_of_post is a moment about the top post top end (center of the cross beam);
M grade is a moment about a bottom of the post;
q H is a velocity pressure at a height (H) of ≤4.5 m in an open terrain;
A is an averaging area (Number of solar panels multiplied by 2 m 2 ); and
L is a nominal chord length, and
wherein the force coefficient GC P , the first moment coefficient GC MHy , and the second moment coefficient GC My are calculated from wind tunnel pressure data obtained by simultaneously measuring a pressure at a plurality of pressure taps embedded in a surface of the first solar panel and the second solar panel.