Proposed Product Label for Electric Lamps Used in the Plant Sciences

Abstract

<jats:p>Electric lamps are widely used to supplement sunlight (supplemental lighting) and daylength extension (photoperiodic lighting) for the production of horticultural crops in greenhouses and controlled environments. Recent advances in light-emitting diode (LED) technology now provide the horticultural industry with multiple lighting options. However, growers are unable to compare technologies and LED options because of insufficient data on lamp performance metrics. Here, we propose a standardized product label that facilitates the comparison of lamps across manufacturers. This label includes the photosynthetically active radiation (<jats:italic>PAR</jats:italic>) efficacy, <jats:italic>PAR</jats:italic> conversion efficiency, photon flux density output in key wave bands, as well as the phytochrome photostationary state (PSS), red/far red ratio, and graphs of the normalized photon flux density across the 300–900 nm wave band and a horizontal distribution of the light output.</jats:p>

Spectral Quality of Light Can Affect Energy Consumption and Energy-use Efficiency of Electrical Lighting in Indoor Lettuce Farming

“…These results suggest that PE is likely not a good predictor of EUE in lettuce production. It is important to note that our results are specific to lettuce and differ from previous research that generally suggested using PE for LEDfixture selection for many species (Both et al, 2017;Nelson and Bugbee, 2014;Park and Runkle, 2018). In contrast to PE, a strong relation was observed between EUE and PE R (Fig.…”

“…Manufacturers of LED fixtures commonly use PE to characterize light fixtures (Both et al, 2017;Nelson and Bugbee, 2014;Park and Runkle, 2018). Greater PE values are associated with lower energy costs of producing artificial light (Kubota et al, 2016) and can thereby increase EUE (Park and Runkle, 2018).…”

Light quality and intensity of light-emitting diodes during pre-cultivation of Picea abies (L.) Karst. and Pinus sylvestris L. seedlings – impact on growth performance, seedling quality and energy consumption

“…The averaged spectral curve was normalized and the values divided into intervals of 100 nm. Since these lamps are intended for plant growth, some of the most relevant values for this purpose were calculated and displayed similarly to how it was suggested by Both et al (2017). One of these values is the photosynthetic photon flux density (PPFD) measured in μmol m −2 s −1 under the PAR region (400-700 nm).…”

Quality, Yield, and Biomass Efficacy of Several Hydroponic Lettuce (Lactuca sativa L.) Cultivars in Response to High Pressure Sodium Lights or Light Emitting Diodes for Greenhouse Supplemental Lighting

“…Examples include photosynthetically active radiation (PAR) efficacy [6], the ability to target specific wavebands/spectra of light, finer control over light intensity and periodicity of lighting [7], and a lower heat load produced in the direction of the light allowing them to be placed closer to a crop or operated during warm ambient conditions [5,8]. When comparing potential for energy savings in LED over HPS lights the PAR efficacy, light output per unit electricity (units: µmol/j) is used [9]. However, PAR efficacy only tells us about fixture performance and does not account for plant performance under a lighting source.…”