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Re: Icemud's Advanced LED XTE Grow - Harlequin - Ogiesel - Black Cherry Cola - Big Po
Hey Kriaze....
LED's are more efficient as they put out more light per watt of energy used so you are correct is saying that a LED's put out more light/watt than an incandescent that is less efficient. So in terms of energy efficiency, LED definitely will provide more light for less wattage, and with less wattage used, then less heat load is added to the sealed environment.
The main point I was trying to make is the wild claims that LED companies like to throw around like "uses 50% less energy" or less heat is only half true. From what I have found, and researched, there is no way for a LED running at 50% of HID to grow the same yield in dry weight...and from what I find, it takes at least 65-85% LED wattage to equal the yield of a HID grow. So in that case LED's can put out slightly less heat than a HID light in a sealed environment with no extraction methods.
Now on the flip side of this, since heat load is converted from KWH to BTU, P(BTU/hr) = 3.412141633 × P(W) where 1W produces 3.412 BTU per hour....
so lets say that you are comparing a 1000w HID vs 800W of LED..
the HID would produce 3140 BTU per hour
The LED would produce 2728 BTU per hour
now the part that I find not true, is that even though you see a difference in about 400 BTU per hour, LED's do NOT have a way to extract the heat directly, where as HID does with Air cooled hoods or cool tubes. LED's push this heat out into the grow environment with no direct method of extraction....
Now if you were to compare equal draw wattages, lets say 1000w(without air cooled enclosures) of HID vs 1000w of LED, then the heat load to a sealed room would be equal because BTU is based on the forumula above, which directly depends on draw wattage. Even though the efficiencies of each light may be different as far as percentage of light produced, the heat load is the same in a sealed environment.
So you are correct, that your 12w lights put out as much light as a 60w incandecent, and are about 1/4 as hot to run. But when looking at LED grow lights vs HID, with only about 20% electrical savings the difference in heat load is not too much different, and without a method of direct extraction, I actually find LED's to warm up my grow environment much more than my HID setup did with air cooled hoods.
Hello Icemud, am still here willing to learn and I appreciate the writeup that you did in regards to LED v HPS heat and I'm wondering whether it may be missing something when comparing pure draw watt heat. Basically I'm currently under the impression that the main reason for difference in temperatures between different light sources is the actual efficiency of the electricity to light conversion.
For instance in my house I use 12w rated led light bulbs instead of 60w rated incandescent. They're as bright as the 60w but still use less of a power draw as they are more efficient at converting the electricity used into light. Basically for an incandescent to achieve the same amount of lumens output it would need to draw more electricity as it has a less efficient conversion rate meaning less light per watt and the extra electricity being converted to heat instead. I was always under the impression that this was the case between LED grow lights and HPS, I think that for a HPS bulb to be as bright as an equivalent LED it needs to draw a lot more electricity to do so meaning much more wasted electricity being converted to heat.
After reading your thoughts on the matter I'm now wondering if there is something that I'm missing. I thought about doing an analogy between cars managing the same high speeds yet managing more miles per gallon nowadays due to better design but really my only knowledge of cars is driving them so I would hesitate to go down that road
I hope everything is well for you and I would love to hear a definitive answer to the heat output led v HP's with the reasoning behind it as I see this question being answered differently a lot on the forums and some clarification would be great.
Happy growing and all the best
Hey Kriaze....
LED's are more efficient as they put out more light per watt of energy used so you are correct is saying that a LED's put out more light/watt than an incandescent that is less efficient. So in terms of energy efficiency, LED definitely will provide more light for less wattage, and with less wattage used, then less heat load is added to the sealed environment.
The main point I was trying to make is the wild claims that LED companies like to throw around like "uses 50% less energy" or less heat is only half true. From what I have found, and researched, there is no way for a LED running at 50% of HID to grow the same yield in dry weight...and from what I find, it takes at least 65-85% LED wattage to equal the yield of a HID grow. So in that case LED's can put out slightly less heat than a HID light in a sealed environment with no extraction methods.
Now on the flip side of this, since heat load is converted from KWH to BTU, P(BTU/hr) = 3.412141633 × P(W) where 1W produces 3.412 BTU per hour....
so lets say that you are comparing a 1000w HID vs 800W of LED..
the HID would produce 3140 BTU per hour
The LED would produce 2728 BTU per hour
now the part that I find not true, is that even though you see a difference in about 400 BTU per hour, LED's do NOT have a way to extract the heat directly, where as HID does with Air cooled hoods or cool tubes. LED's push this heat out into the grow environment with no direct method of extraction....
Now if you were to compare equal draw wattages, lets say 1000w(without air cooled enclosures) of HID vs 1000w of LED, then the heat load to a sealed room would be equal because BTU is based on the forumula above, which directly depends on draw wattage. Even though the efficiencies of each light may be different as far as percentage of light produced, the heat load is the same in a sealed environment.
So you are correct, that your 12w lights put out as much light as a 60w incandecent, and are about 1/4 as hot to run. But when looking at LED grow lights vs HID, with only about 20% electrical savings the difference in heat load is not too much different, and without a method of direct extraction, I actually find LED's to warm up my grow environment much more than my HID setup did with air cooled hoods.
actually was me and my friend I have the copy of it somewhere