Photovoltaic power stations require 25-year service life. Fastener corrosion will change support angle and cause structural collapse. This article tests outdoor service life of six mainstream coatings, formulates regional selection rules for different photovoltaic sites, and standardizes on-site construction protection rules.
| Surface Treatment | Dry Plain Site | Humid Mountain Site | Industrial Acid Site | Coastal Salt Site | Cost Level | Repair Difficulty |
| Color Electro-galvanized | 3-5 Years | 2-3 Years | 1-2 Years | Within 0.5 Year | Lowest | Easy Paint Repair |
| Hot-Dip Galvanized | 16-20 Years | 12-15 Years | 8-11 Years | 4-6 Years | Medium | Local Zinc Repair |
| Manganese Phosphating | 7-9 Years | 5-6 Years | 3-4 Years | Within 2 Years | Medium Low | Oil Re-treatment |
| Dacromet Coating | 20-23 Years | 17-19 Years | 13-16 Years | 9-12 Years | Medium High | Special Coating Repair |
| Geomet Coating | 22-25 Years | 20-24 Years | 18-22 Years | 14-18 Years | High | Professional Spray Repair |
| Zinc-Nickel Alloy | Over 25 Years | Over 25 Years | 23-25 Years | 20-24 Years | Highest | Direct Replacement |
Use hot-dip galvanized fasteners for inland plain power stations, Dacromet for mountain sites, Geomet for industrial surrounding sites, zinc-nickel alloy for coastal tidal photovoltaic projects.
Avoid coating scratch during installation, repair damaged surface in time, adopt same coating for matching bolt, nut and washer, and conduct special inspection after typhoon and rainstorm seasons.