Considering COB's give off less heat does anyone now have issues with low temps ? Are you having to add heating to your grows now ?
cheers
cheers
Lighting Heat vs COB?
- Thread starter Tanglefoot
- Start date
There are basically 3 different types of heat from light, convection, conduction and thermal radiation. Every bit of energy is converted into one of these forms of heat one way or another. The law of conservation of energy fits well as energy cannot be created nor destroyed.
What this means and the references you hear about less heat is really about less convected or conductive heat. While mars hydro has less thermal radiation it is higher in the other categories. Cobs have much higher thermal radiation but still give off heat. Where the benefit is between cobs and mars is cobs convert more energy to light per watt, while still giving off heat. Mars gives off less light per watt while giving off a different type of heat.
In the end a watt of energy is equal to 4.31 btu's of heat no matter what type of light source it is. It's down to how much light you get per watt of energy.
What this means and the references you hear about less heat is really about less convected or conductive heat. While mars hydro has less thermal radiation it is higher in the other categories. Cobs have much higher thermal radiation but still give off heat. Where the benefit is between cobs and mars is cobs convert more energy to light per watt, while still giving off heat. Mars gives off less light per watt while giving off a different type of heat.
In the end a watt of energy is equal to 4.31 btu's of heat no matter what type of light source it is. It's down to how much light you get per watt of energy.
Ive just added in an 80W tubular heater to my tent...the last flat I was growing in was really warm as it was a fairly modern flat....ive now moved to an older house and it definitely gets cold especially now Ive swapped from the HPS to COB setup...but thats because the room the tent is in drops down to 15/16 degrees...so even with the 200W of COBS running its so efficient it just doesnt give off enough heat...but its -2 outside at the moment...as soon as it gets a bit hotter I will be laughing!
as much as im an engineer and 100% believe in energy cannot be created nor destroyed...i ran a 250W MH for a day until I finished my COB setup...the temps were at 27/28...now with the COBS its 200W and its down at 20/21...50W shouldnt be making that much difference...so the same energy goes in but the COB's are just generally cooler or keep the tent cooler...maybe the radiant heat from the light hits the walls of the tent then conduct heat through to the outside rather than directly into the air inside the tent....
To answer your question you will most likely need to add in some heat in the winter if running cobs. You basically don't need as many watts to grow pot like you used to. I have 330w in a 5x5 where I normally would have had a minimum of 600w. That heat savings is like an electric heater running on low.
Wanna fight about it? Lol
just messing. It doesn't seem to make sense to me either. 200btu is not a lot of heat at all. That's basically the difference.
Your an engineer? I think I should have been but instead I build hoses. Talk about a shitty business.
lets dance! it just doesnt make sense to me as i 100% believe in what you say, energy is energy...and he light energy only has one way to transfer to what it hits and thats by changing to heat energy....but it seems to make all the difference!yep...its a good job...get new and interesting projects weekly so keeps the brain active!
Ahhhh man that gave me a good laugh. I was only messing around. This site is a little tense at times.
when those smilies came up i had to use them...cracked me up...dont worry about it ive been on plenty of forums and trust me this forum doesnt seem to give off any bad vibes to me...i just thought as ive actually experienced the difference i would chime in...as you said it makes no sense i might ask one of my lecturers at university and see if they can explain why the temperatures are different and if its just because of the different types of energy given off from the lights...
