While old-fashioned High-Pressure Sodium lamps are still the most favourable choice of many growers, LED lamps gradually become more widely used in horticulture. Obviously because of the energy savings, yet also because reduced radiated heat, enabling new applications in indoor and multilayer grow houses.
Since horticulture lighting is an appealing market due to its size and enormous amount of light points used, many manufacturers are interested in conquering a piece of this market. As a horticulture lighting OEM, you will have to choose from an endless pool of manufacturers when outsourcing manufacturing of your lamps. Here’s a list of the most important supplier selection criteria:
1. Know your light spectrum, light output and light distribution
Although it may seem that plants will grow with any spectrum of visible light, the composition of your light spectrum greatly influences the growth, yields and even shape of crops. Each component of the spectrum containing visible light only or including less visible parts of the spectrum like UV light, or far-red and even infra-red light, may have its particular function in photosynthesis and photo-morphological development of plants. The variety of the crop, combined with daylight, or used in a complete indoor application will end in another selection of light spectrum.
Besides the light spectrum, the total light output (micromoles) and light distribution in the greenhouse need to be factored in as well. Specialized horticulture lighting OEMs will have enough in-house knowledge to select and advise the best lighting solution for the growers. With LEDs, the light output, distribution and the light spectrum can vary from batch to batch (binning), continuously improve with advances in technology and it may be a complex job to manage consistent performance throughout each and every lamp delivered to the market.
The good OEMs work with the suppliers that know the difference between a LED and a LED, and between a micromol and a micromol.
2. Efficacy, heatsink, cooling, size and lifetime
LEDs can be more efficient than HPS lamps. However, only when designed in a luminaire that provides enough cooling to the LEDs. The junction temperature of a LED is practically the most important for the LED efficacy (micromol/J) and lifetime (longevity) of the lamp. To get rid of the heat that the LEDs generate (yes, LEDs also heat up), fixtures need cooling. Passive cooling will require lots of cooling surface, making the luminaire bigger. This can be more costly, and it also will create more shadow in a daylight greenhouse (hence, less free-of-charge daylight can reach the crop). Actively cooled luminaires may be smaller, although forced air luminaires will have lifetime issues due to the hazardous greenhouse environment damaging its fans. Water-cooled luminaires can be small and offer a long life, however may come with higher installation and maintenance cost.
Running the LEDs on a higher current will increase the light output (and reduce the luminaire cost since less LEDs are needed), but it will reduce the efficacy and increase the amount of heat that needs to be cooled away.
The balance between size, lifespan and efficacy needs to be well designed and carefully considered. Your supplier shall know the technical details of every available LED and is involved in the latest developments in LED chip technology in order to assist you in making the right choices and manage these throughout the life cycle of your product.
3. Ingression Protection
Greenhouse environments can be hazardous for lighting equipment. It is not only very humid; various gases used in the production of plants and veggies may also do harm to the luminaire. LEDs particularly are quite sensitive to gases like Sulphur. Even so called ‘protected’ LEDs (these are sold with an internal coating to protect against moisture) may not withstand all situations that occur in greenhouses. Silicon coatings protect relatively well against humidity and water, however are porous for many gases. Proper protection against ingression is crucial for the life span of your luminaire.
The ingression protection, either glass or any other translucent material suitable for the job, mostly need to be glued to the luminaire. Here, again, the adhesive itself may also outgas and damage the LEDs in their early life. Next to the translucent part mostly other possible entries like connectors need to be well designed and carefully chosen for the job.
Suppliers that offer automated lines to apply adhesives consistently and with high precision and suppliers that offer you knowledge about the selection and proper use of adhesives and protection materials obviously are in favor.
4. Project based, local supply and support
Customers in horticulture may want to decide upon their lighting in a very late stadium of their project. And many will only decide at the latest possible moment to choose the final spectrum (daylight alike, or particular colors to achieve certain growth results). A Just-In-Time delivery to your projects with customized project-specific luminaires and light spectrums are just those dynamics that need local suppliers and support. You don’t want containerloads full of costly luminaires sitting on the ocean for weeks and then discover that you just decided to put the wrong light spectrum on stock.
Innovation in LED technology is still moving forward quickly and that will require minimum stock levels as well (to avoid outdated products in stock) and shortest possible lead times so that your customers can always benefit from the latest technology. When well organized, your supplier will have the product design “platformised” in such a way that the basic luminaire parts will be quickly available as standard modules and introduction of new LED chip technology only requires minor component changes.
Besides logistics and innovation, you’d probably also like ease in communication and local tech support to serve your customers swiftly. Remember, light is an essential production means in horticulture.
Yes, of course, cost is also a criterium. Expensive is not automatically the best, and lowest cost may be the cheapest, yet not the best quality. Search for the right cost-performance ratio. Always.
Distant countries may work with lower wages, but the average labor content in horticulture luminaires may be less than 20% and with proper automation even less than 5%. Include transport and duties in the cost and you will find out that differences are close to nothing when you compare on equal quality basis.
Do you want to know more about the manufacturing or assembly of high-quality Horticulture led boards and luminaires? Ask us anything. You are always welcome to visit our high tech production- and assembly location.