15 Arten von Potovoltaik-Halterungen

PV mounting systems are support structures designed to hold photovoltaic (PV) modules in a specific orientation and angle based on the geographical location, climate, and solar resource conditions of a PV power generation system.

As a crucial component of PV power systems, mounting systems directly affect the operational safety, damage rate, and construction investment of PV modules. Choosing the right PV mounting system can not only reduce engineering costs but also minimize maintenance expenses in the long run.

PV mounting systems can be categorized into three types: fixed, tilt-adjustable, and automatic tracking, with their connections typically achieved through welding or assembly. Fixed mounting systems can be further divided into rooftop, ground-mounted, and water-mounted types. The automatic tracking system is known as the single-axis tracking system.

Rooftop mounting systems generally fall into four categories: corrugated iron roof mounting systems, sloping roof (tile roof) mounting systems, flat roof mounting systems, and BIPV (Building-Integrated Photovoltaic) mounting systems.

BIPV stands for Building-Integrated Photovoltaics, a solar PV power generation system that is designed, constructed, and installed simultaneously with the building, seamlessly integrated with the structure. BIPV is also referred to as “building-type” or “building-material-type” solar PV buildings. It acts as a part of the external building structure, serving both as a power generation component and a building component/material. It can also enhance the aesthetics of the building, achieving a perfect unified look with the structure.

Corrugated iron roof mounting systems primarily consist of corrugated iron brackets or fasteners, rails (beams), module clamps, rail connecting parts, bolts, washers, slide blocks, and nuts.

Flat roof mounting systems share similarities with ground-mounted systems. They typically rely on concrete foundations or concrete ballast blocks as the supporting base. Depending on the roof structure, independent foundations or strip foundations can be used. The connection between the foundation and the support column can be achieved using pre-embedded foundation bolts or directly embedding the column into the concrete foundation. Flat roof mounting systems do not damage the roof surface waterproofing layer. They offer flexibility, convenience, and high reliability.

Ground-mounted Systems

• Single-column mounting systems, where the support structure relies on a single row of columns. Each unit has only a single row of support structure foundations. Single-column mounting systems mainly consist of columns, diagonal bracing, rails (beams), module clamps, rail connecting parts, bolts, washers, slide blocks, and nuts. Columns are typically made of C-shaped steel, H-shaped steel, or square steel pipes. Single-column mounting systems reduce land construction requirements and are suitable for regions with complex terrain.
• Double-column mounting systems, which feature front and rear columns. They consist of front columns, rear columns, diagonal bracing, rails (beams), rear support, module clamps, rail connecting parts, bolts, washers, slide blocks, and nuts. The columns are typically fabricated from C-shaped steel, H-shaped steel, square steel pipes, or round steel pipes depending on the size of the array. Other components are constructed from materials like C-shaped steel, aluminum alloy, or stainless steel based on needs. Double-column mounting systems distribute forces evenly, are simple to manufacture, and are suitable for areas with relatively flat terrain.
• Single-pillar mounting systems refer to a mounting system where a single array unit has only one column. Since the entire array has a single column, the number of PV modules that can be installed on a single frame is limited, typically ranging from 8 to 16. Single-pillar mounting systems primarily consist of columns, longitudinal beams, rails (beams), module clamps, rail connecting parts, bolts, washers, slide blocks, and nuts. The columns can be made of steel pipes or prefabricated cement pipes, while longitudinal and transverse beams, due to their cantilevered design, are generally fabricated from square steel pipes. Rails are usually made of C-shaped steel or aluminum alloy. This type of mounting system is suitable for regions with high groundwater levels and abundant vegetation.

Water-mounted Systems
With the advancement of distributed PV power generation projects, utilizing water surfaces such as seas, lakes, and rivers to install distributed PV power stations and implementing new forms of PV agriculture like “fish and solar power combined” has become another solution to overcome the limitations of land resources for PV power generation. Water-mounted systems generally include floating, column-mounted, and offshore PV types.

Offshore PV mounting systems represent a new approach to utilizing marine energy and resources. Compared to land, offshore environments offer advantages: under the same illumination conditions, the sea surface is wide open without obstructions, resulting in longer daylight hours, higher radiation levels, and a significantly enhanced power generation output for offshore PV projects. China has a long coastline and vast near-shore waters, and its coastal regions boast abundant solar energy resources with extended daylight hours. This allows for more efficient utilization of solar energy.

Floating mounting systems are composed of two parts: buoys and support structures. The buoys are fabricated using high-strength materials and connected in a single-body design, ensuring good stability and strong impact resistance, effectively preventing damage to PV modules from various water currents and strong winds. The support structure is typically manufactured from stainless steel or aluminum alloy, materials known for their corrosion resistance.

Column-mounted systems share similarities with ground-mounted systems, but the columns are longer to ensure that the support structure protrudes above the water surface. Additionally, the column materials must be chosen for their ability to withstand prolonged immersion in water.

Tilt-adjustable Mounting Systems
Tilt-adjustable mounting systems have a similar structure to fixed mounting systems but include an additional adjustment mechanism. This mechanism allows for manual adjustment of the mounting system’s tilt angle. The adjustable mechanisms can be segmented or continuously adjustable. Segmented mechanisms typically have 2-3 settings, requiring adjustments 2-3 times per year based on the seasons. Continuously adjustable mechanisms allow for frequent adjustments as needed. To facilitate tilt angle adjustments, the number of modules installed on a single mounting system should be limited to one or two string configurations. Tilt-adjustable mounting systems include push-pull rod, arc, jack, and hydraulic rod types.

Automatic Tracking Mounting Systems
Automatic tracking mounting systems constantly align PV modules perpendicular to the sun’s rays, eliminating the cosine loss of fixed power stations. This allows PV modules to receive more solar energy, thereby increasing power generation output. Automatic tracking systems are typically single-axis tracking systems, where the surface normal of the PV array moves according to the sun’s movement pattern, reducing the angle of incidence of sunlight.

Automatic tracking provides several advantages:

1. Improved solar energy utilization efficiency, increasing the conversion efficiency of the power generation system.
2. Reduced PV module usage for the same power generation output, lowering system construction costs.

Practical experience has consistently shown that power generation output using automatic tracking mounting systems is 15% to 30% higher than fixed mounting systems (single-axis tracking), a finding widely accepted within the PV industry.

PV Mounting System Selection
While the cost of PV mounting systems represents a small percentage of the total PV power system cost, typically only a few percent, its selection is crucial. One of the primary considerations is weather resistance. The mounting system must maintain structural integrity and withstand environmental erosion and wind and snow loads throughout its 25-year lifespan.

Other factors to consider include installation safety and reliability, achieving optimal performance with minimal installation costs, future maintenance-free operation, availability of reliable maintenance guarantees, and recyclability at the end of the mounting system’s lifespan.

When designing and constructing PV power stations, the choice between fixed, tilt-adjustable, or automatic tracking mounting systems should be made based on specific site conditions and a comprehensive assessment of the advantages and disadvantages of each type. These technologies are continually evolving and being refined, and each type offers its own benefits.

Characteristics of Different PV Mounting System Types:

• Fixed Tilt Mounting Systems: Fixed tilt mounting systems are the most commonly used structures due to their simple installation, low cost, and high safety. They can withstand high wind speeds and seismic events. These systems require minimal maintenance over their lifespan, resulting in low operational costs. The only drawback is a lower power output when used in high-latitude regions.
• Tilt-Adjustable Mounting Systems: Compared to fixed mounting systems, tilt-adjustable systems divide the year into several periods, allowing the array to achieve optimal tilt angle conditions in each period, resulting in higher solar radiation than fixed systems throughout the year. Power generation can increase by about 5% compared to fixed mounting systems. Compared to automatic tracking systems, they offer advantages in terms of technological maturity, lower investment costs, fewer failures, and lower operational costs. They represent a practical and economically viable solution.
• Single-Axis Tracking Mounting Systems: Single-axis tracking systems offer superior performance. Compared to fixed mounting systems, flat single-axis trackers can increase power generation by 20% to 25% in low-latitude regions and 12% to 15% in other regions. Sloped single-axis trackers can achieve power generation increases of 20% to 30% in different regions.

In conclusion, choosing the right PV mounting system is crucial for the success of any PV power project. It requires careful consideration of factors such as budget, location, and desired performance. With advancements in technology, there is a mounting system for every need.