Key points
- Production of leafy greens, lettuce of different varieties and herbs, in greenhouses is increasing and becoming more important in terms of food safety, food supply and also is making a greater number of lettuce varieties and other herbs available to consumers anywhere and year-round.
- Supplemental lighting is making production more efficient by prolonging the illuminated growth period, thus shortening time to harvest and increasing return on investment for the growers. Traditional lighting is typically High Pressure Sodium (HPS) lights. HPS lights have been the best available solution, but they also have downsides, which novel LED technology can address. The HPS lights have a poor light spectrum and thus need to operate using high levels of electricity per square meter illuminated. The poor spectrum is naturally best seen during winter, when the role of artificial lighting is accentuated, through lowered quality of the harvest. Use of HPS lights in lower applications is also limited or impossible, due to the high directional heat from the lamps.
- Valoya’s Grow Lights are based on Valoya’s own Light Emitting Diode (LED) technology. Valoya’s AP67 Grow Light produces a light spectrum for the plants, which is optimized to produce high quality plants, using minimal amount of electricity.
Benefits to growers of leafy greens.
- Valoya has tested the Grow Lights extensively with leading research institutions and also verified the results in commercial use at several customers.
- Growers of leafy greens will achieve reduced costs, through lower installed Watts/m2, faster time to harvest, which also means fewer hours of illumination for ready plants. Savings can also be achieved from lower use of water, as the lack of directional heat does not dry the plants or their growth substrates. The very even light distribution from the LED fixtures, enables better uniformity of the harvest, which reduces the need for manual sorting of plants in some case.
- Leafy greens grown under Valoya LED lights grow faster than under HPS lights. This combined with even production and better quality results in higher production rates, which increases revenue for the growers.
- Valoya LED lamps are in use in commercial greenhouses for growing different varieties of lettuce and herbs. Customers include companies, such as Marttila and Virolan Puutarha.
- Tested varieties and/or commercially grown varieties include lettuces summer crisp and different looseleaf varieties, including lollo rosso. Other varities include rocket (arugula) and red-veined dock. Commercially grown herbs include e.g. lavender, oregano, parsley and thyme.
- Typical installation power has been around 45-120 W/m2 and even higher in some special cases. Energy savings compared to HPS have been from about 10% to over 50%.
