Vietnamese scientists are trying to create led lamp products which have the light spectrum suitable with every kind of plant, which can help save electricity, churn out clean and off-season products.
According to Dr Phan Hong Khoi, Managing Director of the high-efficiency public lighting project in Vietnam, LED is a special type of semiconductor diode which can generate a narrow spectrum, discrete light when excited. LED lamps can create different colors, depending on the semiconductor materials used and operating conditions.
With LED lamps, scientists use two beams of light – red (R) and blue (B) with the maximum wavelength of 662nm and 430nm. At that time, the LED spectrum almost coincides with the absorption spectrum of the chlorophyll of plants. Thus, the plants can absorb the light energy at maximum level and turn the LED light energy into cellular energy.
Meanwhile, the highest possible efficiency of using solar energy and white light sources would be 35 percent only.
As such, lighting with LED lamps would bring higher biology energy efficiency, thus allowing to better stimulate the growing of the plants than other familiar lamps. Especially, LED lamps would help save electricity.
Fluorescent lamps used in tissue culture would consume 30 – 40 percent of electricity, and 82 percent in the plant breeding enterprises. Meanwhile, with LED lamps, the volume of power to be consumed would be much lower.
At plantation enterprises, if using LED lamps, one square meter of plantation area would need 0.27 kwh of electricity, while it would need 0.5 kwh with other kinds of lamps.
Scientists have also affirmed that the use of LED lamps in agriculture production would help improve the quality of farm produce, increase the nutrition value and reduce the nitrate concentration in vegetables and fruits. This also allows creating clean off-season products with high economic values.
The experiments have shown that after a short period of lighting with LED lamp, the toxic nitrate concentration has reduced to 44-64 percent.
In addition, to reduce the concentration of nitrate, LED lights would produce less heat radiation than high-pressure sodium lamps, allowing the photosynthesis process to occur more intensity, lasting just a short period instead of the whole growth cycle.
Hundreds of invents in utilizing LED lights in agriculture production have been recognized in China, South Korea, Japan and the US. Meanwhile, Vietnam is just at the very early phase of utilizing LED lamps
Scientists have found out after carrying some research works on daisy and potato plants that the plans grow more rapidly when using LED lamps, while the height and the number of leaves of the plants also increase more rapidly.
Regarding the power consumption, the lighting duration of LED lamp is just a half of other kinds of lamps, four hours instead of eight hours. The research works on tissue culture potato plant also came to the conclusion that LED lamps allow saving 30 percent of the power consumed in comparison with traditional lamps.
However, scientists have reminded that the LED lamps needed could be different in terms of the light spectrum, the B/R ratio, the lighting intensity and duration, depending on the different stages of the plants' development.
They said that the only barrier in using LED lamps is the high production costs of the lamps, but they believe that the barrier would be removed later.
