As we all know, Lumens is for Humans, and PAR is for Plants.
And we all know that watts only measures the electricity going into the light, not the light that comes out of it!
Using wattage comparisions to buy lights is like trying to measure the speed of a car based on its gas mileage data.
Our test compares the results published by www.growace.com comparing multiple 1,000 watt HPS bulbs to the six COB BF3590.6.
GrowAce measured the light output at 15 inches, 27 inches, and 51 inches above the canopy over a 2X2 (four square feet) area. This area is very small compared to the BF3590.6 5X5 footprint for vegetative growing, but we wanted an apples to apples comparison.
Our test measurements were made on the BF3590.6 hung in an Ohuhu 5X5 grow tent at the same height as the HPS light. We used the Apogee MQ-500 PAR Light Meter with quantum sensor. Nine readings were taken in the same pattern as used by GrowAce.
Results at 15 Inches above canopy:
Why would anyone position a light only 15 inches away over a 2X2 space? Anyway, here are the results:
The BF3590.6 with Cree CXB3590 Chip On Board LEDs produces just about the same amount of light as the 1,000 Watt HPS.
Results at 27 inches above canopy:
This distance is more likely to be used in a practical growing situation. The BF3590.6 performs better than the 1,000 Watt HPS light:
Results at 51 Inches:
At 51 inches, the BF3590.6 is able to provide excellent vegetative growth in a 5X5 grow tent, but the 1,000 Watt HPS light is struggling to provide enough light for vegetative growth in a 2X2.
The Broomstraw Farm BR3590.6 grow light delivers full spectrum light better than a 1,000 Watt HPS light at about half the electrical cost! Why would anyone even consider HPS for a new grow room?