The Lighting Research Center (LRC) at Rensselaer Polytechnic Institute has developed a free online tool, the horticulture luminaire calculator, to assist growers evaluating the performance, efficiency, and economics of a wide variety of horticultural luminaires, typically used in greenhouses and other controlled agricultural environments. The horticulture luminaire calculator enables growers to compare different luminaires and choose the optimize solutions for their applications.

(Image: LRC)

Horticulture lighting is become more significant with indoor farming and high-tech farming applications increasing across the globe. But since these lighting systems are expensive to purchase and install, it is critical for users to better understand if they are using the most suitable lighting system for their targeted applications.

LRC developed the horticulture luminaire calculator developed based on a metric called photosynthetic photon flux density (PPFD). PPFD is analogous to photopic illuminance on a work surface in an architectural application. Just as it is only valid to compare the power densities of alternate lighting systems at equal illuminance levels on the work plane, the power densities of alternate horticultural luminaires should only be compared when they provide the same PPFD on the plant canopy.

The tool allows growers to inspect and compare all the factors including luminaire efficacy, luminaire intensity distribution, optimal luminaire layout, and the number of luminaires to evaluate the overall cost-effectiveness of various horticulture luminaire options.

“Energy use and lifecycle costs vary widely among LED lighting systems used in controlled environment horticulture,” said LRC Professor Dr. Mark Rea. “It has been the standard approach for many years in the field of architectural lighting, and is becoming readily apparent in horticultural lighting, that we must conduct complete system energy and lifecycle cost analyses to generate an accurate picture of which technology would work best for each particular application. The horticulture luminaire calculator provides an easy way for growers to make this determination.”