I’ve never veged with far red. I’ll put a few in a veg room tomorrow and see if anything weird happens.
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This was the best quick example of light efficiency could find. BTU’s can be absorbed by the plant as light energy and regulated as well. It is how it works, and a well designed room see serious reductions in operating cost.
In the example above with the 600W luminaires, the HPS luminaire will dissipate approximately 55% of the 2,046 BTUs as radiant heat directed toward the crop by the reflector while the LED will be as low as 27% as radiant heat. Also, the HPS will deliver approximately 34% of that energy in the visible light wavelength, while the LED will deliver 40-50% of it’s BTU energy as visible light (and is why the LED is more efficient). Vice versa the HPS luminaire only transfers approximately 11% of its total BTUs in the form of convection heat, while the LED will have 25-30% of its total BTUs dissipating through convection.
Just because they are light btus doesn’t mean you don’t have to cool them…
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No your plants do… you guys just keep doing your thang. You could always gasp try some
I’ll owe you one for that, I don’t know why I never thought of them, I know I still wanted to try them in the flower room.
Um, you’re aware I work everything from 1000 hood HPS setups to roughly 600 fixture 700w bar led(gavita, luxx type) to high wattage (fohse) leds right? All them need their cooling calculated the same way… Total watts×3.412 then add derating for ambient and humidity.
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I understand how an engineer is going to balance BTU’s. I also have worked in very large facilities of varying tech, and for some odd reason, the LED operations are always running leaner, producing and moving better flower… Shrugs. I’ve literally seen same wattage footprint pay 60% less in consumables. But ok.
I’m not saying leds aren’t more efficient. Most de setups with a good bulb are around 1.9-2.1 ppe. I agree with @Ralf, I won’t even begin to consider an led unless it’s above 2.5ppe. But to get to 55% more efficient you would need an led around 3.0ppe. That’s a unicorn that probably won’t exist for at least another year.
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Just another reason I prefer led. PPE is a flawed metric for cannabis. UV and FR are so important. Like 10-23+% of the energy/radiation I want.
Ppe? Do explain, I’m ignorant
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Efficiciency calculation, micromoles per joule.
LED rooms require more dehumidification for some reason which was causing additional watts to be consumed to keep the rh in check
My buddy switched his rooms over from single ended hps to led and didn’t notice any change in power bill because of the dehues running more. Yield was larger for sure so the plants could be drinking more
Tricky topic I also thing growing styles can fit either or
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Hps and halides warm surfaces, though. And then that material absorbs and holds the heat. It doesn’t seem the same with led.
There’s the gavita specs for the 1700e led and 1000e hps…just over 3.412 btu per watt for both…I’m not making this up.
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Sure. I’m just saying that hid lighting creates thermal radiative heating that led does not. The heat is stored in the mass of the room and accumulates.
My grandpa used to leave a 150 watt hps on in the barn in winter for his animals. Dogs and cats would lay under it to get warm. An led would not be the same, even if the btus were similar.
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You guys have clearly never been around a gavita 1930e or Fohse o6i. Of course the bar style leds don’t feel hot due to their surface area. Put the same watts in to a similar for factor to a de and it feels the same.
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Led lights heat the air, and that heat quickly disappears. But heating surfaces is different. The heat accumulates in those surfaces. I wish I had ever taken a real physics class. I only know these things from being around hps lights in cold dank basements.
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Heat can’t disappear. You can’t create or destroy matter, mearly change its state. Yes a 645w led feels cooler than a 1000w hps cranked up to 1200w. Now instead of replacing a 1200w light with one 645w light, replace it with 2 and let me know. I literally have 100kw led rooms next to 100kw hps rooms. The heat load is the same. The difference is if both are dialed in, the hps room will pull 3lbs per 20 square foot, the led will pull 4lbs per 20 square foot. That is directly comparing luxx de to fohse o6i.
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Correct. Except you mean energy and not matter. The amounts of both are finite in the universe, of course. But in a typical grow room, of any size, what matters is how quickly the heat leaves the room. Heating air is the fastest way for the heat to escape. Heating mass is very different, depends on the room, but that heat does not go away the same.
If you were cold right now and desperate for heat, and I offered you the equivalent btu in lights for your warming comfort in led vs hps…would you really pick the led? I wouldn’t. I don’t think my grandpa’s barn cats would, either.
In your opinion yield aside what room would you say puts out the best quality? I’ve been seeing a lot of talk the last two weeks that people are saying that the reduction of quality is partially due to led vs hps. My buddy ran some of my genetics under led, I basically steered his garden for him and the yield was better then my cmh and the flower looked good but the terps weren’t even close to the same.