LED system with independent red and blue channels employing radiant flux estimation and indirect flux control for greenhouse hop cultivation

Abstract

Hops are quite susceptible to weather and radiation. As such, it is a complex task to cultivate hops out of its natural habitats, in low latitude outdoor locations. This paper proposes an indoor alternative to cultivating hops on a small scale for brewery applications, employing a two-channel LED lighting system. Its main component is a driver for a specific R+B LED load, which controls the radiant flux of both red (R) and blue (B) LED strings independently. This LED array was developed specifically to meet the hops' lighting needs, and its photo-electro-thermal (PET) model is considered to estimate and control precisely each of the radiant fluxes emitted in real time. The driver and R+B LED array are used inside the greenhouse which guarantees the adequacy of other abiotic parameters for the crop. An experimental routine is proposed and underway for comparative results between the proposed LED versus conventional fluorescent lighting for growing hops under same environmental conditions.