Types and Characteristics of Photovoltaic Support

  Photovoltaic support directly affects the operation safety, damage rate and investment cost of photovoltaic modules.

Photovoltaic Bracket Type

Material

  According to different materials, photovoltaic supports can be divided into aluminum alloy support, steel support and non-metal support.

Installation Mode

Fixed Photovoltaic Bracket

Best Inclination Fixed

  First, calculate the best local installation inclination angle, and then all arrays are fixedly installed with this inclination angle, which is currently widely used in flat roof solar power systems and ground solar power systems.

1.Flat Roof-concrete Foundation Support

  Currently, the concrete foundation bracket is the most commonly used in the installation of photovoltaic systems in flat roof houses. The support column and concrete can be connected by anchor bolts or the support column can be directly embedded in the concrete.

Advantages: Good wind resistance; Strong reliability; Will not damage the roof waterproof structure.
Disadvantages: Long construction period(the support can only be installed after the concrete foundation has been made in advance and has reached enough strength).

2.Flat Roof-concrete Ballast Bracket

Advantages: The construction method is simple; Save construction time(the bracket can be installed while making the counterweight).

Disadvantages:The wind resistance is relatively poor, so the local maximum wind force should be fully considered when designing the weight of counterweight.

3.Ground Solar Power System-Concrete Foundation Support

a. Cast-in-place Reinforced Concrete Foundation

Advantages: Less material usage; Lower cost; Faster construction speed.

Disadvantages: Easily restricted by environmental factors such as seasons and weather; Higher construction requirements; Cannot adjust again.

b. Independent and Strip Concrete Foundation

Advantages: Simple construction method; Strong geological adaptability; The embedded depth of the concrete foundation can be relatively shallow.

Disadvantages: Huge works; Long work cycle; Great damage to the environment.

c. Precast Concrete Hollow Column Foundation

  The precast concrete hollow column foundation is mainly used for Solar Power systems with poor geological conditions.

4.Ground Solar Power System-Metal Pile Support

a.Screw Pile Foundation Support

b.Impact Pile Foundation Support

Advantages: There is no need to excavate the ground during the installation of the bracket, which is more environmentally friendly; Not limited by seasonal temperature and so on; Fast and convenient work, short work cycle; Adjustable height during pile driving.

Disadvantages: Piling is difficult in areas with poor soil environment; poor corrosion resistance.

Inclined Roof Fixed

  The load-bearing capacity of sloping roofs is generally poor, so the components are generally installed flat.

1.Tile Roof Solar Power System

  The tile roof installation system is mainly composed of hooks, guide rails, clamps and bolts.

2.Color Steel Tile Roof Solar Power System

Angle Adjustable Fixed

  The adjustable fixed inclination angle refers to the regular adjustment of the inclination angle of the fixed support at the turning point of the change of the sun's incident angle, so as to increase the direct sunlight absorption and increase the power generation with a slight increase in cost.

Tracking Photovoltaic Bracket

Comparison and Selection of Steel Support and Aluminum Support

Material Strength

Steel: Q235B

Aluminum Alloy：6063 T6

  The strength of 6063 T6d is 68%-69% of Q235B, so it is generally preferred to choose steel in areas with strong winds and large spans.

Deflection

  Under the same conditions, the deformation of aluminum alloy profile is 2.9 times of steel, and the weight is 35% of steel. At the same weight, the cost of aluminum is three times that of steel. Therefore, steel is superior to aluminum alloy profile in strong wind area, large span and cost.

Anticorrosion Performance

  At present, the main anti-corrosion method of the bracket is hot-dip galvanized steel 55-80μm, and aluminum alloy is anodized 5-10μm.

  The aluminum alloy is in the passivation area in the atmospheric environment. A dense oxide film is formed on the surface of the aluminum alloy, which prevents the surface of the active aluminum matrix from contacting with the surrounding atmosphere. Therefore, the aluminum alloy has very good corrosion resistance, and the corrosion rate decreases with time.

  In addition, the steel can be galvanized in high salinity zone for more than 20 μ m in normal seawater, and the corrosion rate can be accelerated in high salinity zone (c1-80 μ m), even in high salinity zone.

  In terms of corrosion protection, aluminum alloy is far superior to steel.