Understanding Wattage in LED Grow Lights

Posted by Josh Powell on October 11th, 2018

Grow Lights and the Myth of the LED Wattage

If you’ve been spent any time researching LED grow lights, then you’ve may have noticed often times manufacturers list a wattage rating on their models.  At first, you may think that the more Watts on the packaging the better.  Unfortunately, this is not always the case. With most LED grow lights on the market today, those claimed numbers are simply inaccurate.  This is because they often represent the maximum output of the LEDs of the given light, but the lights are usually not capable of anywhere near this output.  For example -  A 3W LED is typically running at 1-2W in order to extend the life of the LED. Many manufacturers list 100 3W LEDs on a light and label it as a 300W light). 

In conclusion, be wary of the manufacturer's claims. The stated number of Watts and the actual Wattage given off by the light can be must different. 

One solution to this dilemma is to buy a PAR meter and test the wattage yourself. This involves placing the LED grow light at different heights, over above a flat cardboard grid pattern. Then run the light at full strength to determine how powerful the output is. Again, most grow lights will fall short of the stated wattage claims. Often times, Chinese manufacturers are the biggest offenders in misstating wattage. That's not to say US and European manufacturers don't do the same, because they do, but not nearly as frequently. 

Hopefully, this information won't discourage you from looking into LED grow lights because their benefits certainly outweigh those of traditional grow light options. LED grow lights tend to be more expensive at the point of purchase, but over the long run, they end up being cheaper to running (electric costs) and more efficient in terms of growing plants. Consider a full spectrum grow light - with reds, blues, whites, UV, and IR - to get the most out of your grow. Ideally, you want a grow light that comes as close to the sun's rays as possible, and full spectrum LED grow lights are your best bet.