The Parameters – Commercial LED Grow Lights vs. Traditional HPS 1000 Watt HPS and DE HPS
For the review Black Dog LED provided twelve PhytoMAX 800 LED grow lights to the commercial grow facility. The PhytoMAX 800 runs at 800 watts and includes the proprietary Black Dog LED Phyto-Genesis Spectrum® including ultraviolet light to increase quality. The goal was to test the PhytoMAX 800 against two different lighting configurations that had all been run in the exact same room.
Commercial Grow Lighting Configurations:
The following three configurations are examined in this case study:
- (12) ducted 1000 watt single-ended HPS fixtures, with ballast load wattage assumed to be 1025W per light, not including any power usage from ducting fans for cooling purposes. This was the standard setup for this room and the ducting was professionally installed and the glass lenses are completely cleaned along with the rest of the room between each flowering cycle and the bulbs are changed on a regular basis based on age.
- (10) un-ducted double-ended (DE) Gavita HPS Lights; with the ballast adjusted to 1000W per bulb, these fixtures pulled 1055 watts each at the plug. It should also be noted that it was not possible to run 12 of these fixtures in this specific test room due to cooling issues associated with running the DE fixtures (which cannot be ducted) and introduce a significant amount of heat into the commercial grow environment. This model of DE HPS are used in other rooms throughout the operation.
- (12) Black Dog LED PhytoMAX 800 grow lights, running 800 watts each, placed in the same configuration as the 12 ducted 1000 watt HPS, but without the ducting. The hanging height for the PhytoMAX is important and the hanging system available in the room allowed the lights to be hung at the proper height and adjusted as necessary. One of the additional advantages of the LED grow lights compared to HPS is the lack of issues with hot-starts so some of the electrical infrastructure to protect against this was not necessary when using the PhytoMAX lights.
The specific test room was selected due to it being independently ventilated and monitored. While other rooms in the same facility were more or less identical to the test room, they share cooling equipment and therefore cannot be isolated from one another. This test room was selected for the case study because the data collected for not only the lights but also for the HVAC would be for the single room where the review was being conducted.
The only change to the growing environment besides lighting was to increase the ambient temperature of the garden to 85 degrees Fahrenheit so the leaf surface temperature of the plants in the LED grow were the same as with the HPS lights based on our research on leaf surface temperature. This increase in ambient temperature is one part of the potential savings offered by PhytoMAX grow lights in a commercial setting, due to the decrease in cooling requirements when compared to the same space being run with traditional HPS or DE HPS. When the ambient temperature was adjusted for the duration of the commercial grow the savings amounted to a roughly 50% reduction in cooling power consumption.
While many growers are understandably reluctant to increase ambient temperature in flowering areas to 85 degrees, this test grow experienced no negative impact from the ambient temperature increase. Hundreds of other test grows have demonstrated the same results; while keeping temperatures cooler is critical to avoiding stress, pests and mildew issues when using HPS lighting, plant leaves – and the pests and diseases that may live on them – are kept cooler with the Black Dog LED Phyto-Genesis Spectrum®. Running at an ambient 85 degrees with PhytoMAX LEDs is equivalent to running at 75 degrees with HPS lights.
Aside from the lighting and temperature changes, all other variables remained the same- the same room, with the same insulation, nutrient regimen and personnel were used with all of the lighting configurations. This was done to eliminate as many variables as possible and focus solely on the performance of the lights being tested.
The physical layout of the grow environment with different lighting configurations are diagrammed above next to each configuration description. Above is a picture of the commercial room 5 days after being filled with plants and 2 days after being flipped to flower. The test room itself was 15’ wide by 28’ long with two grow benches running the length of the room that were 24’ X 4’ which held the plants.
In all lighting test cases the room was set up the same with the lights spaced evenly over the length of the grow benches, whether there were 6 lights on each side for the ducted HPS and the PhytoMAX 800 configurations, or 5 lights over each bench with DE HPS. The room contained 39 plants.