What Factors Should Be Considered When Designing The Layout of Photovoltaic Support Structures

The layout of photovoltaic (PV) support structures directly affects the power generation efficiency, economic feasibility, and ease of construction of a solar power plant. Key factors to consider include:

1. Consideration of Sunlight Conditions

• Orientation: The ideal orientation for PV supports is towards the true south (for the northern hemisphere), as this maximizes solar radiation and improves power generation efficiency. However, in practical situations, adjustments can be made within a certain range from due south based on the specific location and sunlight characteristics of the installation site. Generally, deviations of up to 30 degrees from due south have a relatively small impact on power generation efficiency.

• Tilt Angle: The tilt angle of the PV supports should be optimized based on the local latitude and seasonal variations. In the northern hemisphere, the tilt angle is typically set close to the latitude of the location to ensure that the PV modules receive fairly uniform sunlight throughout the year. For different application scenarios and needs, more precise tilt angles can be calculated and simulated to enhance power generation efficiency during specific periods or seasons. For example, in regions with higher power demand during summer, a slightly lower tilt angle can be adopted, while in areas with higher winter demand, the tilt angle can be increased.

2. Site-Specific Factors

• Roof Installation: When installing PV supports on a building roof, consider factors such as the roof shape, area, load-bearing capacity, and nearby obstacles. Typically, flat or sloped installations are used to maximize roof area, while ensuring that the installation does not affect the roof’s waterproofing or the building’s structural integrity. If the roof has parapets or other obstacles, the support layout must be planned carefully to avoid shading that could reduce efficiency.

• Ground Installation: For ground-mounted PV plants, the layout is generally more flexible but must still consider land utilization and topographical features. Typically, rows of panels are arranged in a linear or staggered pattern to ensure sufficient spacing between the PV modules, prevent shading, and facilitate construction and maintenance. In hilly or mountainous regions, the supports should be arranged with varying heights to adapt to the terrain, ensuring that the PV modules are well-aligned with the natural landscape to receive more sunlight.

3. Safety Spacing Requirements

• Module Spacing: To avoid shading between adjacent PV modules, which would reduce energy efficiency, the spacing between modules should be determined based on the local solar altitude angle and the size of the modules. Typically, the spacing should be 1.5 to 2 times the height of the module to ensure that the modules receive adequate sunlight throughout the year.

• Row Spacing: For multiple rows of PV supports, the row spacing needs to be designed carefully. This spacing must not only prevent shading from the front row on the back row, but also allow space for personnel and equipment access for maintenance. Generally, row spacing should be between 3 to 5 meters to facilitate construction, inspection, and cleaning operations.

4. Electrical Wiring Layout Considerations

• String Box Location: When planning the layout, consider the placement of string boxes to facilitate electrical connections between the PV modules. The string box should be placed centrally within the array or near the power connection point to minimize cable length and reduce losses, thereby lowering system costs. Additionally, ensure that there is adequate space around the string box for operation and maintenance.

• Cable Channels: Design reasonable cable channels to ensure that cables between PV modules are laid neatly and orderly. These channels should avoid interference with the support foundations or other structures, and protective measures should be taken to prevent mechanical damage or corrosion of the cables. The cable channels should also allow for heat dissipation and drainage to ensure the safe operation of the cables.

5. Wind and Snow Load Considerations

• Wind Resistance: Depending on the wind conditions at the installation site, the structure and layout of the PV supports should be designed to improve wind resistance. In areas with high wind speeds, it may be necessary to increase the number of support columns, enlarge the cross-sectional dimensions of the columns and beams, or add bracing systems. Additionally, when arranging the supports, consider the wind direction. For row-based layouts, orienting the long side of the supports perpendicular to the prevailing wind direction can help reduce wind load on the structure.

• Snow Resistance: In areas with heavy snowfall, consider the potential accumulation and sliding of snow on the PV modules. The tilt angle of the supports can be adjusted to allow snow to slide off naturally; typically, a tilt angle greater than 45 degrees will make it easier for snow to slide off. Special snow removal devices, such as vibrators or heating wires, can also be installed to prevent snow buildup, which could damage the modules and reduce power generation efficiency.

By taking these factors into account, the layout of the PV supports can be optimized to enhance efficiency, durability, and ease of installation, ensuring the long-term success of the solar power project.