"Growers know that if they get more light, they get more yield”

The grow light space is a wild west in its own right. The number of LED options available on the market has grown rapidly in recent years, making it harder for growers to find lights that meet their quality standards. But an expanding marketplace is simply a reflection of the rising popularity of LEDs among growers. “In 2017, there was a breakthrough for luminous flux an individual LED creates,” says Randy Shipley, independent representative for Surna Cultivation Technologies. “The Design Light Consortium (DLC) created a Horticultural Qualified Products List (QPL) for utilities to use for rebates which can validate how many total photons a fixture produces based on reports from independent labs. Using the Horticulture QPL, growers can compare the total output, wattage used and amount of photons in each spectrum  and can also be reassured that those are actually real numbers.”

New indoor facility build-outs are deploying LEDs more often than not
“More cultivators are opting to grow with LEDs,” Randy continues. “But, the majority of existing facilities are still using HPS. This has somewhat to do with the fact that retrofitting entire facilities can be quite financially intensive, particularly in areas without utility rebates. HPS has proven over time to grow quality product and many old school growers are not willing to take the risk and cost of transition.”

There are many differences between HPS and LEDs, known by a large majority of the growers. To successfully transition from HPS to LED, it is crucial to know how such differences influence the growing environment. “The most important factor will be temperature control,” Randy points out. “HPS radiates heat directly under it, so you need more cooling to cool that area. This means a bigger load on the HVAC because growing with HPS necessitates a room temperature of around 77F. This creates a leaf level temperature of 84F when measuring the temperature directly below the HPS fixture. On the other hand, with LEDs, you would need less cooling. The overall room temperature can stay at 84F which maintains the leaf level temperature at 84F, the sweet spot for cannabis.”

Until the past year, LED fixtures did not create enough Photosynthetically Active Radiation (PAR) to replace HPS fixtures without placing the LED fixtures close to the plants – typically requiring the fixture to be twelve inches or less above the canopy.  “This created different problems for growers,” Randy says. “LEDs are nothing but printed circuit boards and chips, which are powered by drivers with special housing to disperse heat created by the chips. Drivers can heat up and retain some heat, similar to a ballast on an HPS fixture. Placing the fixtures closer to the plants can create a rat’s nest of cables and wiring. This poses potential risks to workers’ safety, as well as complicating maintenance if needed.”

Following the science 
LEDs are driven by direct current (DC). This requires the use of a driver to convert alternating current (AC) to DC. It is important to understand the efficiency of a driver as all drivers will intake more AC than the DC output. A simple example is a driver that takes in 100W AC and outputs 95W DC is 95% efficient. Another driver may take in 100W AC and only output 92W DC which would be 92% efficient.

Given these common challenges with LEDs, Surna Cultivation Technologies has partnered with BVV to offer a new LED fixture that is detached from a quality, high-efficiency driver for the conversion of AC to DC. The BVV Neocision Spectra fixture is listed on the DLC website and has the highest amount of micromoles under 700w.

These LED designs were based on scientific findings and took into consideration the teachings of Bruce Bugbee. “Our LEDs come with a full spectrum based on extensive scientific research,” Randy explains. “There is a lot of talk about what far-red can do to plants. They have seen how one-seventh of far-red in lettuce and basil increases the yield by 70%. This is because it inhibits the growth and makes the leaves larger. This is a highly desirable outcome in leafy greens, but not in cannabis. In cannabis, you can use it in the vegetative state, but in flowering it will create added stretch and weaken the plants, decreasing yields.”

According to Bugbee, growers should have 20% blue. “Surna’s LED fixtures follow these recommendations,” Randy adds. “There is no need to use blue chips which are more costly as we use a full spectrum white chip that produces more blue photons. The LED fixture Surna offers spikes the red by using more red chips than other leading manufacturers. This creates a spike between 600nm and 700nm. The red spectrum of light (600nm – 700nm) is the most important type of light for plants. When it comes to photosynthesis, plants are best able to make energy out of red light. In fact, many plants can actually grow even if they only get pure red light, though they will not grow as big or as healthy as they do under full spectrum light.“

These lights are perfectly suitable for both veg and flower. “Again, we follow the science, and it says that a plant needs enough total across the broad spectrum of light. We explain the science of lighting to growers in simple terms. Growers intuitively know from years of experience  that if they get more light, they get more yield,” Randy continues.

With the increased light output of 1935 PPF as compared to high quality double ended HID fixtures of 1750 PPF, the new lights are hung higher above the plant canopy for increased work room. With increased height and the use of customized daisy chain power cables, the rat’s nest of cables has been solved.  “That’s why we have designed cable harnesses, and we do that also for racks,” Randy points out. “It allows you to cut installation costs, plus you have no loose cable. All of this is custom-designed, and it is safety-approved. Our components are UL certified as required by local building codes and insurance companies. With the experience of Surna and our custom designs, installation costs decrease. Generally speaking, a grower can save about 40-60 dollars per light installation. If you consider how large these facilities are, these installation savings are quite significant.”