Characteristics of Sediments in Offshore Photovoltaic Area and Their Effects on the Erosion–Deposition Variation

Offshore photovoltaics construction has become an important direction of new energy development. There are few case studies on the impact assessment of sedimentary environment and erosion–deposition variation of pile foundation fixed photovoltaic in open coastal water. Taking the proposed offshore photovoltaic project as the research object, this paper uses field investigation and evaluation and numerical simulation to analyze in detail the possible impacts of the construction and operation of such projects on the Marine environment from four aspects: sediment environmental characteristics, hydrodynamics, erosion–deposition variation and suspended sediment. The results show that the sediment type of the project area is mainly silty sand, and the sediment quality is in good condition. The operation of the project will cause a slight decrease in the current velocity value in the area, but the change value is generally no more than 1%. The project has little impact on the hydrodynamic environment in the nearby area. The degree of deposition in the sea area where the project is located increases slightly, but the change value is generally less than 1%. Therefore, the project has no significant impact on the erosion–deposition variation in the nearby sea area. Suspended sediment caused by pile foundation construction will have a certain impact on the water quality of the surrounding sea area. Considering that the suspended sediment content after construction will quickly recover to the background value, the actual impact range of suspended sediment is much smaller than the predicted range, and its impact on seawater quality is limited.