1. Structural Characteristics

• Venlo-type Structure: A popular choice for large-scale commercial use, characterized by a multi-span, multi-roof layout. It offers excellent space utilization and is highly compatible with advanced environmental control systems.
• Arch-type Structure: More common in small to medium-sized setups, its curved roof design enhances snow and rain drainage while simplifying construction.

2. Key Properties of Polycarbonate (PC) Sheets

• Exceptional Light Transmittance: PC sheets achieve a light transmittance of 80%–90%, comparable to glass. With a UV-protective coating, they resist yellowing, fogging, or reduced transparency even after long-term exposure to sunlight—transmittance loss is typically less than 10% after a decade.
• High Impact Resistance: Their impact strength is 250–300 times that of ordinary glass, 30 times that of acrylic sheets of the same thickness, and 2–20 times that of tempered glass. This "unbreakable glass" quality effectively withstands hail, strong winds, and accidental impacts.
• UV Protection & Anti-Condensation: One side of the PC sheet is coated with UV inhibitors to block harmful ultraviolet radiation, protecting plants and internal materials from damage. The other side features an anti-condensation treatment, preventing water droplets from forming and dripping onto crops (which could cause disease).
• Lightweight: With a density only half that of glass, PC sheets reduce transportation, handling, and installation costs. They also minimize the load on the greenhouse’s support framework, lowering structural material expenses.
• Flame Retardancy: Classified as Grade B1 (flammability rating for difficult-to-ignite materials), PC sheets have a ignition point of 580°C. They self-extinguish when removed from the flame and do not release toxic gases during combustion, enhancing fire safety.
• Flexibility: PC sheets can be cold-formed or heat-formed on-site according to design plans (e.g., into arches or semi-circular roofs). The minimum bending radius is 175 times the sheet thickness, allowing for diverse architectural shapes.
• Thermal Insulation: PC sheets have a much lower thermal conductivity than glass and other plastics. Their insulation efficiency is approximately 200 times higher than glass and 8 times higher than ordinary plastic films, maintaining stable indoor temperatures (warmer in winter, cooler in summer) and reducing energy consumption.

3. Supporting Equipment

• Environmental Monitoring & Automation: Sensors for temperature, humidity, CO₂ concentration, and light intensity collect real-time data. An intelligent control system adjusts equipment automatically based on preset thresholds for crop needs.
• Ventilation Systems: Combined natural ventilation (sidewall and ridge vents) and mechanical ventilation (exhaust fans, circulation fans) ensure air circulation, regulate temperature, and reduce humidity.
• Shading & Insulation: Internal/external shading nets block excess sunlight in summer, while thermal screens retain heat in winter.
• Cooling & Heating: Evaporative cooling pads (paired with fans) lower temperatures in hot weather, and infrared heaters or hot water pipes provide warmth in cold conditions.
• Irrigation & Fertilization: Drip irrigation, spray irrigation, or hydroponic systems deliver water and nutrients efficiently, synchronized with environmental controls for optimal crop growth.

4. Applications

• High-Efficiency Cultivation: Growing fruits (strawberries, grapes, dragon fruit), vegetables (tomatoes, cucumbers, lettuce), flowers (phalaenopsis, roses, tulips), and Chinese medicinal herbs—enabling off-season production and extending growing cycles.
• Eco-Tourism & Education: Serving as eco-restaurants, botanical gardens, or agricultural exhibition halls, combining horticulture with sightseeing and science popularization.
• Scientific Research: Providing a stable, controllable environment for crop breeding, pest control studies, and climate adaptation experiments.
• Specialized Breeding: Supporting high-value aquaculture (e.g., ornamental fish) or poultry farming, with environmental controls tailored to animal needs.