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100% New to Growing and Resident Noob - LED or HPS? HPS heat concerns me.

19 posts in this topic
3 hours ago, cultivateur said:

Even the most efficient LED panel will be chucking out roughly the same amount of heat as the equivalent wattage of HPS - i.e 600 watt lamp = nearly 600 watts of heat.


I can't believe people are still giving out this bullshit to new growers.


My PC draws about 250w idle admittedly its a high end gaming machine with a hungry CPU under load that's closer to 700w... 50w for a low power laptop maybe... The point here is the amount of heat we are talking about regardless of the source is not going to light him up like a Christmas tree on FLIR. If you think otherwise you're entitled to your opinion. But you're not doing anything to address the concerns raised by the OP.


If you think a 600w HPS is throwing out 600w of heat then how much of the energy is converted into light? That's a seriously inefficient setup... Let's say the average HID is 30% efficient then 420w of the 600w is converted to heat and 180w is converted to light. Nowhere near the 600w of heat you state. Now 60% efficiency is easily achieved on an LED setup so 600w of LED provides 360w of light and 240w of heat. 


This doesn't mean that LED's are cold but they are better at converting energy into light that is a simple fact. Sure some of the energy will always be lost as heat but a larger % is turned into light. 


Alternatively you can call bullshit (based on not much at all as far as I can tell) but there is a large and growing body of evidence that disagrees with you... 


Keep it green 

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It should be noted that 420w of heat and 240w of heat in a 1m x 1m tent is more than enough to raise the ambient air temperature to the desired level do not confuse what I've written above with me saying "An LED will keep your space cool" 


Hope that makes sense 

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I see nothing much has changed in the 5 years since I got fed up arguing with LED fanbois and left.


We are now at the point where if you're prepared to spend a crazy amount of money, you can build or buy LED lights with comparable performance even to double-ended HPS lamps.

I still don't know why one would outside of a research greenhouse where other factors come into play.

I recently replaced an ignitor in one of the 250 watt HPS lamps I bought at Sunlight Systems in 1995 ... built like tanks they are. And I'd always been led to believe that magnetic ballasts are so lossy, they chuck out 50 watts of heat, but my steel boxes don't get hot enough to contribute much to warming my rootzone.


... whereas my current seedlings are being kept toasty - not just from the red hot sheet of LEDs over them, but also from the LED strips keeping some ornamentals ticking over on the shelf below.


Suffice to say I have no little experience in experimenting with lighting of all kinds.

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33 minutes ago, cultivateur said:

I see nothing much has changed in the 5 years since I got fed up arguing with LED fanbois and left.


CMH fan boy maybe...


I'd argue we are a bit further along than that. Unless yield is all that concerns you, sure it's not as cheap as HPS but you get what you pay for... 


The fact is that the more "natural" spectrum on offer from these newer technologies grows better weed. Even @oldtimer1 has commented to that effect about CMH.


Anyway this is getting derailed from what the OP was asking. 


Nice side step though

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