THE STATUS IN GREENHOUSE LIGHTING OF LED AND HPS
-Author ：LeDinPro
2019 /2/12
In recent years, insufficient greenhouse lighting has attracted more and more attention. In the future, the relatively closed production system of greenhouses will play an important role in meeting the demand for food growth.
Insufficient greenhouse crop illumination due to climate change, such as frequent smog weather, rainy weather in winter and early spring directly adversely affect greenhouse crops, causing severe production losses. The grow lights can effectively alleviate or solve these problems.
Incandescent lamps, fluorescent lamps, metal halide lamps, HPS, and emerging led grow light have all been used in greenhouse light supplementation. Among these types of light sources, HPS with higher light efficiency, longer service life and higher overall energy efficiency occupy a certain market position. But HPS has poor illumination and low safety (including mercury), problems such as close-range exposure are also prominent. Some scholars have a positive attitude toward LED lights in the future or can overcome the problem of insufficient performance of high-pressure sodium lamps.
The HPS is the third-generation illumination source, which has the advantages of wide application range, high luminous efficiency, strong penetrating ability and long service life. However, HPS is a kind of heat source. During use, it is accompanied by the generation of heat, there is also a problem of self-extinguishing.
As the fourth generation of new semiconductor light source, Led grow lights adopts DC drive, and its lifetime can reach more than 50,000 h, and the attenuation is small. As a cold light source, it can be placed close to the plant. Compared with LED and HPS, it is not difficult to find that Led grow lights are safe, contain no harmful elements and are more environmentally friendly.
As LED grow lighting applications expand, more and more practitioners are paying attention to LED bio-lighting opportunities. For example, In Canada, the annual sales of greenhouse fruits and vegetables exceed US$1.1 billion. How to provide effective illumination for greenhouses is the key to supporting greenhouse cultivation and increasing revenue. In terms of yield, even in moderate temperatures, nutrients and sufficient water, greenhouse cultivation will be affected by limited light. Researchers at McGill University in Canada believe that the current way of supplementing light in greenhouse cultivation, such as traditional HPS, is not the most effective source of light for plant growth, so actively use led grow light as alternative lighting.