HPS LAMPS DOUBLE ENDED
When designing a lighting plan for the greenhouse, the uniformity of light is as important as its intensity.
The high-pressure sodium lamps (HPS) are the most common choice for having a high additional light intensity in the production of crops in greenhouses. The traditional HPS lamps works with magnetic power supplies, but the new electronic power supplies which are typically smaller, quieter and between 10 and 15% more efficient. In addition, electronic power supplies are much lighter and the light emitted from the bulb degrades at a slower speed compared to the use with a magnetic power supply.
When Double Ended HPS lamps were born?
Until yesterday the HPS lamps were just "single-ended" type, it means that the lamps are connected via a single connection. In 2005, Philips has developed and marketed HPS lamps for use in greenhouses called "double-ended" (DE), today there are several brands that produce different models in use, and wattage.
what are the HPS lamps DE and what they offer?
These bulbs are connected to the mains with 2 connectors. The glass is quartz and are 5 cm smaller than the HPS single-ended. The amazing thing about the DE's that are 25-30% more efficient than a normal HPS single-ended, data confirmed by Utah State University (UT, United States). The Double Ended HPS lamps have a wide range of voltages including 120, 208, 240, 277, 347 and 400 volts and usually are designed to work in pre-asseblati systems from 1000 watts.
Example of the efficiency of HPS lamps Double Ended, micromoles per 30 cm2:
- HPS Lamps Single-ended (Philips): 1550 micromoles
- HPS Lamps Double-ended (Philips): 2100 micromoles
Modern electronics ballast (power supply) can be dimmable and often they have the option of supercharging Lamp(super lumens). You can, for example, bring a bulb HPS DE 1000W to a final power of 1150W obtaining a surprising increase of light intensity, up to 2415 micromoles (estimated).
How much the indoor DE lamps costs?
The HPS DE Lamps combined with electronic power supplies and specific reflectors are more expensive than traditional HPS systems (SE) and the bulbs are more expensive at the time of replacement but their sustainability in terms of efficiency pays the additional investment within a few months of use.
How do they use HPS Double Ended lamps in the greenhouse?
When using high intensity light as for the HPS Double Ended 1000W in the greenhouse, the distance from the plant must be at least 150 cm.In case you are using a too short distance uniformity of light decreases, creating a highly luminous hot spots under the lamp and lighter and cold spots between the lamps. When designing a 'lights plan', the uniformity of light is just as important as its intensity. If the light intensity is uneven, the growth of the plant becomes too variable and lead to different irrigation needs. This phenomenon can be particularly problematic in the production of young plants.A Consult with the IDROPONICA.IT specialists to discuss and address the many different options for your greenhouse.
A common question is how much additional light do I need? It depends mainly from space, and the cultivation techniques used. Generally speaking, the indoor growers of ornamental plants and young plants should provide between 50 to 75 mol · m-2 · s-1 of additional light.