LED Grow Light specifications include the Wattage, or Power of the light. However, there is a great deal of confusion over Wattage and actual Power Draw. Why are there even 2 different specs and how does the customer decipher what is really going on? For example, the G8-90RR Flower Booster by G8LED has 90Watt in the name but the actual power draw as stated on the product spec page is 80 Watts. Why??
Power (Watts) = Voltage(110 or 220) x I(Current)
LED plant lights are grouped by the current (Amps) of the diodes within the light. 1-watt diodes generally run at around 0.35 Amps, 2-watt diodes run around 0.5 Amps and 3-watt diodes run around 0.7 Amps. Diodes are not maximized with current so that the manufacturer can increase the lifespan, reduce the heat output, and supply a better grow light. In addition, different colors require a different voltage. The red and orange wavelengths require around 1.8-2.7 Volts and the blue and violet wavelengths require 2.7-3.5 Volts. Hence, following our W = V x I equation, a 3-watt red diode may only have a power draw of 1.5-2.0 watts, and a blue diode may only have a power draw of 1.8-2.5 watts. That is why we have the stated wattage of the light and the actual power draw. Hence, the 90 Watt grow light has 90 x 1-watt diodes but the actual power draw is 80 Watts.