For greenhouse operations in the North China, Northeast, and Northwest regions, the headache during winter is the energy consumption and heating issue. With the current heating methods in place, reducing energy consumption in greenhouses becomes particularly important. So, how can we, with our commonly used multi-span film greenhouses, achieve energy-saving through double-membrane methods? Today, we share several simple approaches with you from the multi-span film greenhouse industry.

For greenhouse structures in the North China, Northeast, and Northwest regions, the winter headache is often the energy consumption and heating issue. With the current heating methods in place, how to reduce energy consumption in greenhouses becomes particularly important. So, how many methods are there to reduce energy consumption through double-layering in our commonly used multi-span greenhouse structures? Today, we share a few simple methods with you from the perspective of multi-span greenhouse structures.

I. Method for forming a double-membrane structure on the top film of a multi-span greenhouse

1. Double-arch double-membrane design on the beams of the connected film greenhouse

This structure is located above the beam, with an additional layer of an arch, an outer arch, and an inner arch, spaced approximately 50 centimeters apart, creating an insulating layer between the top and bottom. This skeletal structure does not occupy the space beneath the pillars, but its drawback is that the support rods of the inner arch cannot reach the outer arch, resulting in slightly reduced snow resistance.

The upper section of the multi-span film greenhouse trusses features a round arch, with an additional layer of curved arch structure below. The lower circular arc is positioned beneath the truss, with a design gap of approximately fifty centimeters between the truss and the lower arc. Even if an internal shading system is installed on the truss, it will not interfere with the lower arc. The advantage of this arched structure design is that the support rods of the outer arch can extend to the outer arch, providing strong resistance against snow. However, the drawback is that the inner arch of the lower layer occupies too much space in the pillars, requiring pillars of at least four meters or higher.

3. Simple Cable Tension Membrane Design for Multi-span Film Greenhouse

This circular arch greenhouse structure maintains a single-layer design, with a steel wire rope suspended below the inner transverse beams and another along the upright pillars. However, the steel wire rope on the pillars is lower than that in the middle of the span, creating a sloping roof where the film can be directly fastened.

The advantage of this design is its cost-effectiveness and simple installation, but the drawback is that once the inner membrane is securely fixed, it becomes difficult to open and close it daily. It can only be removed when spring arrives and the warmth is no longer needed. The first two methods allow for the installation of roller shutter ventilation systems, enabling the opening and closing of the inner membrane.