Hi
@bicit
please consider the following aspects, you might change your mind
... I remember my 600W MH to run warmer than my 600W HPS (on same digital ballast) when I used to make the switch from veg to flowering ... but that's not very reliable data....
... I also remember my temps slighlty droping when switching from magnetic ballast to digital, more efficient, less direct heat being thrown away ... but that's not reliable data either.
1) Speed of light, as previously stated, has nothing to do with anything here.
2) You are saying that the amount of light used by our plants is really marginal and can be discounted ... that's funny from a grower POV when the desired end product is the direct result of this "marginal" amount of light (...) and we now tend to have higher and higher PAR / optimal spectrum, "to be wasted light" within the spectrum is decreasing relative to total light emited. => goodbye unneeded infrareds for instance .. ie direct heat
3) Did you actually measure actual wattage of your CFL ??
I remember from long times ago that most (all ?) CFL run at a lower wattage than advertised. A lot of 125W CFL actually run at 93W (...)
=> If not, that is proportionally a HUGE difference, 126/96 = 1.3125 You might be comparing "same wattage" with the leds actually using +30% more juice... so same temps would be proof that leds run cooler.
4) If both setups are indeed of same wattage :
a) Did you actually measure temperatures in same conditions, same amount of canopy, same ambient temps ?
b) We get quickly used to improvements, maybe if you switched back you would then notice the extra heat ... you used to have
5) If your light is really twice as efficient, you should be able to cover twice the area (so half the energy for a given space ...)
If you are using it in the same space and canopy, you might have gone in overkill mode, overkill mode by definition means your plants are using % less of the light available, so more of it becomes heat ..
6) Your plants swet to cool down and when water changes state it stores alot of energy (see
enthalpy change of formation). The amount of folliage has a big influence on your temps. A room with clones will get warmer than a room with a dense canopy, but humidity will rise instead ...
7) (Marginal but ...) Different spectrums will not be performing equally. Red light is more readily absorbed => less reflections, less heat compared to a bluer or geener spectrum. Red light has more photons per radiometric watts too ..
Finally : Seriously, if you are still so sure, consider doing this experiment :
If what you say was 'kind' of correct, a 1000W heater at full blast wouldn't put (much) more heat than 1000W of leds. Try in 2 growbox, I beleive a couple of hours into this test, you will have sufficiently convincing data ...
Have you looked at the speed of light lately? For our purposes with the distances light has to travel in the grow room, this is practically instantaneous. Energy doesn't lazily drift from state to state.....
OK so that last part isn't quite true in all situations.... but for this example it is.
Now this is assuming a sealed room. Air extraction changes things considerably.
I tried replacing a 125w self ballasted CFL in a tiny closet with 126 watts of vero 18's with the drivers located outside the room. Same temperature problems despite being over twice as efficient... Had to pull out one of the lights to get the temps where I liked them, even then I still had to leave the door propped open.
Why argue over semantics?
The aim is to be able to understand and predict how to manage waste heat (temperature, whatever) from the LED array in the grow room. Anyone who has practical experience with this problem, please share your findings and anecdotes!
some are ventilated in the form of steam, released as heat when and if it condensates (I wouldn't count this as it's happening (at least a part of it) outside of a grow space). Another part of the energy is stored in chemical bonds.