Hello -- Glad to help; I apologize for not replying sooner -- No, in fact most LEDs do not consume their rated wattage, and why you will read about more 'really-into-it' growers using Kilowatt meters to know how much their lights cost them a day/week/month (A kilowatt meter is about $15-$20 on Amazon, and since they can be used for almost any household appliance buying one is not a tip-off to anyone about anything except the fact that you are cost-conscious about electricity.). There are several reasons for the disparity in wattage and what it means for LED lamps, but I believe the simplest is the fact that LEDs get their rating (300W, 450W, etc.,) based on what the diodes are capable of handling, not what they will produce in actual light on a plant -- for example: a 3W LED going into a 300W lamp will typically have 100, 3W individual lights--or some portion of 100; the exact number depends on which exact diodes are being used. If the manufacturer is using the newer 5W LEDs, you can do the math -- The LEDs draw less than their rated maximum power for several reasons and that has to do with how an individual lamp is designed/made. Power efficiency figures in, along with a desire by the manufacturer (and us as purchasers,) to not have lamps that run 'all-out' to the point that they will have a shortened life expectancy, or, burn out altogether very shortly after being turned on the first or second of 10th time--but well under the advertised lifetimes that are estimates only. In a worse case scenario, LEDs can overheat and burn out or literally burn. Over-amping a design is a problem with some LED grow light makers--they try to get away with having the least number of LEDs in a fixture, so they push the individual lights to the max, which usually means they run hotter, burn out more frequently, or give light that varies in intensity/quality. Because a 300W LED doesn't usually draw a full 300W, the best guide to how much energy the plants get is the lumen rating, or its PAR level -- PAR is the rating that most LED plant growers consider as the most accurate way to value a lamp--Generally, the higher the PAR, the more deeply it will penetrate into your plants' canopy and the wider area it will cover at a useful distance from growing plants -- That being said, the advice here on GWE about thinning the canopy to let more light in; to give more light for every cola you grow -- these are all good practices. The site has some good primers about LEDs, so be sure to check those out. Generally, I hear that high-intensity discharge lights (the MH and HPS lights you hear growers discuss,) are better for ripening buds than LEDs and CFLs, but high-intensity discharge lamps are generally more of a headache in terms of power draw and heat dissipation. But the benefit with MH and HPS is that you pretty much get a huge abundance of light (perfect for ripening buds,) compared to just about anything else except natural sunlight....I am trying to compensate by having more LEDs in a grow tent, but the trade-off is that I now have a grater heat issue. In the long run I may grow with LEDs for the Veg cycle, but bring in HPS for the flowering/ bud ripening stage...
