Lighting Design Research For Horticultural Vegetables Growing: A Case Study

The aim of this research was to explore the lighting system's requirements for a product, conceived for indoor plant growth, with a technological analysis, selection and mixing, of optimal coloured and white LED light sources. A prototype has been realized with attention to colour mixing, light intensities distribution and thermal management. The prototype has been measured and evaluated in terms of the Photosynthetic Active Radiation (PAR), which is the wavelengths of light in the range of 400 to 700 nm which activate photosynthesis and the Photosynthetic Photon Flux Density (PPFD), that define the amount of PAR that actually reaches the plant. The research hypothesis is that SSL systems are a new opportunity for efficient, reliable and qualitatively horticultural cultivation, and we provide guidelines and insights derived from a functional prototype tried out for this purpose, in order to cultivate both low, medium and high level requirements crops. In particular, it is evident the importance of diffusive materials for optical control to provide the best colour mixing and the best canopy efficiency.