Photovoltaic roof mounting systems (also known as PV support structures) serve as the critical components connecting solar panels to building roofs. Their design and selection directly determine the system's safety, power generation efficiency, and service life. Below, we systematically elaborate on the core functions and implementation methods of these mounting systems across three dimensions: structural stability, tilt angle adjustment, and wind and snow load resistance.

1. Stabilization: Transfers all loads from photovoltaic modules—including self-weight, wind loads, and snow loads—to the roof structure (roof panels, beams, walls), ensuring the roof itself is not overburdened.

Preventing Displacement and Collapse：The mounting system is securely anchored using bolts, embedded anchors, counterweights, or anchoring devices to prevent displacement, tilting, or collapse during high winds, earthquakes, or construction activities.

Materials and Corrosion Protection Common materials include hot-dip galvanized steel, aluminum alloy, or stainless steel. A hot-dip galvanized coating ≥60 µm (≥80 µm in coastal areas) prevents corrosion and extends support lifespan.

Anchoring can be achieved by: - Pre-embedding steel anchors in the roof structure, with brackets bolted to them; - Placing concrete or metal counterweights beneath brackets to apply gravitational pressure against the roof (suitable where roof penetration is prohibited); - Drilling through the roof waterproofing layer using waterproof sleeves, allowing bolts to penetrate directly into the roof structure for the most direct load-bearing path.

2. Tilt Angle Adjustment (Power Generation Efficiency Optimization)

Optimal Tilt Angle The tilt angle of photovoltaic modules determines the amount of solar radiation they receive. The optimal tilt angle varies by region and season, typically ranging between 15° and 30°.

- Fixed Tilt Mounting System: Features a one-time tilt angle setting, offering simpler structure and lower cost.

- Adjustable Tilt Mounting System: Enables fine-tuning via bolts, hydraulic, or electric mechanisms, suitable for seasonal adjustments or specific needs (e.g., changing roof obstructions).

Azimuth (Orientation) Mounting systems also enable optimal south-facing (Northern Hemisphere) or north-facing (Southern Hemisphere) orientation to maximize annual power generation.

Preventing Module Shading Proper tilt angle and mounting spacing design prevents inter-module shading, enhancing overall power output.

3. Wind and Snow Resistance (Extreme Climate Adaptation)

Wind Load: Wind pressure generates horizontal and vertical forces on the support structure. The structure must possess sufficient bending and shear resistance to prevent displacement or structural failure during severe winds (e.g., typhoons, tornadoes).

Snow Load：Snow weight imposes vertical static loads, particularly in northern or high-altitude regions. Mounting systems require adequate load-bearing capacity and incorporate tilt angles to facilitate natural snow shedding.

Vibration and Resonance Prevention Large-scale PV arrays may vibrate under wind loads. Mounting system stiffness and damping design must prevent fatigue failure caused by resonance.

The design of photovoltaic roof mounting systems must strike a balance between structural safety, power generation efficiency, and climate adaptability. Through proper selection, code-compliant installation, and regular maintenance inspections, the mounting structure provides a solid foundation for the PV system, ensuring safe, reliable, and efficient operation throughout the project's entire lifecycle.