Multi-span greenhouses are advanced agricultural facilities that connect multiple independent greenhouses via gutters (drainage channels), forming a large-scale, continuous production space. They have far surpassed the simple concept of traditional greenhouses, evolving into modern “plant factories” that integrate environmental control, logistics management, and data-driven decision-making, representing one of the highest levels of facility agriculture.
The powerful functionality of a modern multi-span greenhouse relies on a complex set of subsystems working in concert.
Ventilation System:
Roof Vent System: Utilizes a rack-and-pinion mechanism to electrically open roof vents, enabling natural ventilation through the thermal pressure effect.
Side Vent System: Provides supplemental ventilation.
Fan-and-Pad System: A forced cooling combination serving as the primary summer cooling solution.
Shading and Insulation System:
External and Internal Shade Screens: External screens actively reflect sunlight for cooling, while internal screens provide both shading and nighttime insulation.
Insulation Curtains: Closed during winter nights to significantly reduce heat loss, achieving energy savings of 40%-60%.
Irrigation and Fertilization System:
Widely employs integrated water-fertilizer technology, utilizing drip irrigation and sprinkler systems for precise, efficient nutrient and water management.
Supplemental Lighting System:
During winter or overcast/rainy days with insufficient natural light, LED plant lights or high-pressure sodium lamps supplement illumination to ensure normal crop growth.
Intelligent Control System:
This serves as the greenhouse's “brain.” Environmental data is collected via sensor networks, analyzed by environmental computers or cloud platforms, and used to automatically control all equipment operations, enabling unmanned precision management.
IV. Primary Application Scenarios
Premium Vegetable Cultivation: Year-round production of off-season, high-value fruits and vegetables such as tomatoes, cucumbers, bell peppers, and strawberries.
Floriculture Production: Specialized cultivation of cut flowers or potted plants like Phalaenopsis orchids, roses, and lilies.
Seedling Propagation: Providing uniform, robust vegetable and flower seedlings for field cultivation.
Plant Factories & Research: Utilized for new variety trials, agricultural technology research, and related scientific applications.
