Nowadays in greenhouses LEDs are being used more and more. The LEDs have become more efficient, and they can be easily placed within the crop so light loss can be strongly reduced. However, the most optimal placement for light loss reduction is hard to predict or measure. WUR Greenhouse Horticulture has a 3D model to virtually test the effect of LED systems on light distribution and subsequent crop photosynthesis.
Within the 3D modelling platform GroIMP, developed at a German university, we first built a 3D crop. Then the model simulates the distribution of light from sun, HPS and LED lamps. The emission pattern of the lamps is exactly as quantified by the lamp producer. The crop structure is derived from a series of experiments carried out at WUR Greenhouse Horticulture. The light model is multispectral, so the light penetration of the different light colours can be predicted with the aid of optical properties of leaves, stems, greenhouse objects etc.
An interesting model option is that the leaves can attain the colour they absorb most. Thus we get an image of the distribution and utilization of a specific light colour, caused by properties of lamps and crop. The model will soon be utilized in some large research projects.