# Wind Load Distribution in Float Photovoltaic System
## 2 PV Generation System
### Mooring System  
Most of the anchors used in conventional floating PV are gravity anchors that resist loads with their weight. However, in floating PV power plants, the load transmitted to the anchor from the mooring line is generated by the wind load on the power plant and the fluctuations caused by the movement of the water surface, and these loads are very difficult to predict. In addition, in the case of gravity-type anchors, the gravity-directed load can be simply predicted by its weight, but for horizontal forces, the friction force between the anchor and the ground is very difficult to predict, so it is problematic to predict the clear behavior related to ensuring overall mooring safety.  
Figure 2 shows the load transfer mechanism for the floating PV structure. As shown in Figure 2, the mooring force due to the wind load can be estimated as a result of this study because all the loads applied to the PV panel are superimposed and transmitted to the mooring.  
If the structure is placed continuously, the movement of the water surface may cause excessive bending moment loads on the structural members and destroy them, so it is competent to design and connect them at a certain length. Buoyancy materials applied to floating structures include concrete, steel, PE (Polyethylene), EPS (expanded styrofoam), EPP (expanded polypropylene), FRP (Fiber Reinforced Polymer), etc., depending on the application of the structure. But in floating solar power, plastic-based materials are mostly used for environmental, construction, and economic reasons. Buoyancy is the most important structural parameter to keep the PV plant on the water surface as it transfers the self-weight and gravitational loads of the plant to the water.  
Therefore, long-term durability against buoyancy is a primary design concern, so not only short-term structural safety due to impact loads but also long-term durability against UV (ultraviolet) must be secured, and in terms of maintenance, it must be easy to repair and replace.  
Mooring is a facility that fixes the displacement of the floating solar power plant, and while buoyant bodies resist gravitational loads, mooring must effectively resist rotational and horizontal loads. Considering the weather conditions in Korea, the water surface conditions also show excessive water level differences as the dry season and flood season are extreme.  
Especially in the case of dams, the maximum water level difference can be more than 100 m, so the water level difference must be reflected in the design. When the water level drops, the power plant is likely to drift as the mooring line slackens, and when the water level rises, the mooring line pulls the power plant, causing the power plant to be submerged or destroyed. In addition, fixing the rotational displacement is also an important design factor for economic reasons, as the power generation is better when the solar module faces south.  
In a conventional solar power plant, the structural facility transfers the load to the ground, and in a floating solar power plant, mooring plays a similar role to the foundation. The mooring system of floating PV power plants is divided into mooring lines and anchors, and mooring lines are mainly made of plastic materials, wire ropes, chains, etc. These ropes  
Figure 2: Load transfer mechanism for floating PV farms.  
and other structural materials are only tension members, which can effectively resist tensile forces under applied loads but cannot resist compressive forces. Therefore, all loads acting on the anchor from the floating solar power plant are tensile forces acting in the opposite direction and horizontally to the direction of gravity.