The plant factory is a high-efficiency facility agriculture system that achieves annual continuous production of crops through high-precision environmental control in the facility. The computer automatically controls the temperature, humidity, light, CO2 concentration, and nutrient solution during the growth of crops. A brand-new production method that is not or seldom restricted by natural conditions.
Plant factories are recognized internationally as the most advanced development stage of facility agriculture, and it is one of the important indicators to measure the high-tech level of a country’s agriculture. At the same time, plant factories are considered to be an important way to solve population, resource, and environmental problems in the 21st century, as well as an important means to achieve food self-sufficiency in the process of future aerospace engineering, the moon and other planets.
Generally, plant factories can be divided into two types: solar plant factories and artificial light plant factories. The two types of plant factories have differences in the background value of UV radiation and the regulation of the UV light environment. Sunlight plant factories usually use semi-closed glass greenhouses or solar greenhouses as the maintenance structure, and use sunlight as the light source. Therefore, the UV radiation distribution characteristics in it are closely related to the materials of glass, sunshade nets and shed films. In greenhouses and greenhouses, covering materials (glass, plastic film, high-quality anti-aging film, etc.) absorb, block and filter natural light.
Generally, the transmittance of the covering material to visible light is about 88%, and the transmittance of ultraviolet light is only 15.9% to 21.1%. Compared with the open field, omentum and glass can filter out most of the UV-A and UV-B, the UV-A and UV-B in the solar plant factory are significantly reduced, and the ultraviolet radiation is significantly reduced. According to reports, the UV-B irradiance at noon on a sunny day is about 0.5W/m2, while that in the glass greenhouse is only about 0.075W/m2. In addition, UV radiation in solar plant factories is also affected by supplementary light lamps, because high pressure sodium lamps (HPS) or ultraviolet lamps contain UV radiation.
Artificial light plant factories usually use closed light-proof buildings as maintenance structures, and artificial light sources are used as plant light sources (such as fluorescent lamps and LED lights). The intensity of ultraviolet radiation depends entirely on the amount of ultraviolet light in the artificial light source spectrum. Artificial light plant factories depend on the UV content of the lamps. Fluorescent lamps contain very little UV radiation, and the UV radiation in non-UV-LED lamps is almost zero. Therefore, the UV-A and UV-B radiation in the artificial light plant factory is very lacking, or even completely absent.
Distribution characteristics of ultraviolet light in plant factories
The plant factory is a high-efficiency facility agriculture system that achieves annual continuous production of crops through high-precision environmental control in the facility. The computer automatically controls the temperature, humidity, light, CO2 concentration, and nutrient solution during the growth of crops. A brand-new production method that is not or seldom restricted by natural conditions.
Plant factories are recognized internationally as the most advanced development stage of facility agriculture, and it is one of the important indicators to measure the high-tech level of a country’s agriculture. At the same time, plant factories are considered to be an important way to solve population, resource, and environmental problems in the 21st century, as well as an important means to achieve food self-sufficiency in the process of future aerospace engineering, the moon and other planets.
Generally, plant factories can be divided into two types: solar plant factories and artificial light plant factories. The two types of plant factories have differences in the background value of UV radiation and the regulation of the UV light environment. Sunlight plant factories usually use semi-closed glass greenhouses or solar greenhouses as the maintenance structure, and use sunlight as the light source. Therefore, the UV radiation distribution characteristics in it are closely related to the materials of glass, sunshade nets and shed films. In greenhouses and greenhouses, covering materials (glass, plastic film, high-quality anti-aging film, etc.) absorb, block and filter natural light.
Generally, the transmittance of the covering material to visible light is about 88%, and the transmittance of ultraviolet light is only 15.9% to 21.1%. Compared with the open field, omentum and glass can filter out most of the UV-A and UV-B, the UV-A and UV-B in the solar plant factory are significantly reduced, and the ultraviolet radiation is significantly reduced. According to reports, the UV-B irradiance at noon on a sunny day is about 0.5W/m2, while that in the glass greenhouse is only about 0.075W/m2. In addition, UV radiation in solar plant factories is also affected by supplementary light lamps, because high pressure sodium lamps (HPS) or ultraviolet lamps contain UV radiation.
Artificial light plant factories usually use closed light-proof buildings as maintenance structures, and artificial light sources are used as plant light sources (such as fluorescent lamps and LED lights). The intensity of ultraviolet radiation depends entirely on the amount of ultraviolet light in the artificial light source spectrum. Artificial light plant factories depend on the UV content of the lamps. Fluorescent lamps contain very little UV radiation, and the UV radiation in non-UV-LED lamps is almost zero. Therefore, the UV-A and UV-B radiation in the artificial light plant factory is very lacking, or even completely absent.