As the saying goes: what kind of pot has what kind of cover. Nowadays, it is not a magic thing to install photovoltaics on the roof, so are all photovoltaics installed on the roof the same? The answer is definitely no. Depending on the user's roof structure and installation area, the photovoltaic system design and installation will also vary. This article introduces several conventional rooftop photovoltaic installations.
Judge roof construction conditions
1. Utilization area: First of all, determine how much available area the roof has, because the available area directly determines the installed capacity of the photovoltaic system. Secondly, the direction of the roof is best to face the south, because we are in the northern hemisphere when we face south, the power generation is the highest, and it is ideal to receive solar radiation. It can also be slightly eastward or westward, generally within a few degrees or about 10 degrees, and it is acceptable to control the loss of power generation to within 1%.
2. Blocking: Blocking is very critical for the solar power generation system. Blocking includes blockage of buildings and whether there are tall trees around the building that affect lighting.
3. Waterproof: To judge the waterproof condition of the roof is to see whether the roof has a very good waterproof layer. If the building does not have a good waterproof system, the use of the roof may not be satisfied within the life cycle.
4. Version and anti-corrosion are the basic requirements for roofing: firstly judge whether the type of metal roof can be installed, and anti-corrosion is to pay attention to the anti-corrosion effect of the metal roof.
5. Load-bearing. The photovoltaic system must be built on the roof. If the roof's carrying capacity cannot meet the photovoltaic construction, this project will not be established.
The photovoltaic system's own safety and building safety include fire prevention, lightning protection, and maintenance access. All contact points must be effectively protected. The lightning protection must be integrated with the building's lightning protection. The maintenance channel is for safety during maintenance and must be reserved.
Slope roof photovoltaic system installation
1. The roof tile on the pitched roof is used as the decoration material of the roof. Are the battery panels hung on the roof?
When selecting the structure, there are two characteristics of the installation method: 1. The photovoltaic module mainly adopts a sloping overhead installation method. The photovoltaic array is laid in parallel with respect to the roof, and the bracket adopts a steel matrix embedded beam fixed beam;
2. The vertical distance between the photovoltaic module installed along with the slope bracket and the roof meets the requirements of the installation and ventilation clearance (the overhead distance is generally 150 ~ 200mm).
The installation method of the bracket should pay attention to the hanging tile and the water bar is connected to the fixed tile. The second is the form of lying tiles because the terracotta tiles are pasted to the tiles through concrete, there is no water strip, and they can only pass through concrete.
As a new material, the roof of linoleum tile is gradually being used more, because the linoleum tile is removed and restored again, and if it is not properly controlled, it will leak water. Therefore, the method used is to increase the connection position where the fixing point is connected. The linoleum tile has a certain thickness, which forms a certain space. It must be filled with sealant before and after fixing to avoid water leakage Hidden danger.
Flat roof photovoltaic system installation
The structure selection of a flat roof can choose the corresponding support system according to the actual practice of the roof finish surface. The bracket system is generally composed of four parts: a column, a foundation, an inclined beam, and a beam. The battery assembly is connected to the beam using fasteners. (Weight: 0.35 ~ 0.50kN / ㎡)
Installation inclination angle: the inclination angle corresponding to the maximum value of the local annual total power generation is used as the installation inclination angle of the bracket (theoretical calculation value);
Common house structure forms: cast-in-situ concrete frames and floors, steel structures + cast-in-situ concrete floors, brick-concrete structures + precast floors;
Common roof finishes: waterproof membranes, cement mortar protection, ceramic tiles.
The mounting method of the flat roof is U-shaped steel, which is a very thin thin-walled profile or an aluminum alloy profile. With these two types of materials, steel profiles have lower cost, high strength, stable structure, self-heavy weight, and aluminum alloy profiles have high cost and lightweight. Compared with the two construction costs, steel profiles are about 0.2 yuan/watt lower than aluminum profiles.
Color steel tile roof photovoltaic system installation
Color steel tiles are generally used in home factories or large industrial plants. The difference between its installation method and the pitched roof is that the support installation method is different. The color steel roof is a color steel plate with a clamp on it, which is clamped on it for support.
Its function is that the installation angle is installed along the slope of the roof. If the structural bearing capacity of the roof can be met, the inclination angle can be raised to increase the installation angle. Common roof panel system, vertical edge snapping, vertical edge locking system, profiled steel plate system (veneer or sandwich).
There are several important considerations in the design scheme of the color steel tile roof power station:
1. Define the form and laying method of photovoltaic modules and the roofing form of the original building.
2. Understand the structural form of the original building and calculate the main structural stress components.
3. According to the roofing form, the structural form of the original building, the arrangement form of the photovoltaic array, the form of the photovoltaic module itself, the structural calculation results, and possible construction measures, etc., a variety of feasible support arrangements are given to determine Optimal arrangement.
4. The rooftop photovoltaic project has its construction particularity. Considering the site construction conditions comprehensively, the appropriate construction technology is selected, and the precautions during construction and the safe construction measures for construction protectants are given.