I'm open to objective data on LEDs. It's just that I've seen very little of it. What I have seen in controlled, side-by-side grows using the same plants, same nutes, same power, and same time table grows by experienced growers show LEDs producing inferior results. There is so much obvious hype out there that I am reluctant to invest a huge sum of money in unproven technology when there is much cheaper technology with a long and proven track record. I have researched some of the LEDs on the market to find their sources in China and have found there to be a 400% markup on their prices. I have also found several seemingly knowledgeable persons who state that one needs 75% of actual wattage LED compared to HID to achieve equal results. The power savings don't justify the huge outlay for the LEDs. At least you posted some helpful information on appropriate manufacturers. I had thought that Epistar and Bridgelux were supposed to be quality brands. Now you're saying they're crap? My understanding was that the biggest factor was in the heat management. Along with proper spectrum. There is conflicting data on that. I find that some of the LED growers seem a little too emotionally invested in their expensive lights to be objective. And of course there's the sellers with a financial stake in promoting the lights. My point is, until there is better info available, why take a risk? As I said before, HID is proven technology.
Hey man. I maybe got a bit too excited when saying bridgelux and epistar where crap. Thay are good quality leds, only those have not yet met the higher efficiency other brands are showing. So let's just say, they are good, but there are better ones out there available. It is true what you are saying. One of most important things when talking leds, is thermal management. The more a diode gets heated, the more it loses it's efficiency. The more you can properly disipate the heat, the more you could squeeze out of that led without loosing neither efficiency nor lifespan.
Best quality leds, have a better thermal management. There is a spec about leds that is important. Their Junction Temp. This tell us their individual thermal efficiency. You can control the heat from the moment it "leaves" the diode from the back part on it's base. bBut you can,t control the inner heat, that inner heat, is measured by the Junction Temp. This datum, tells us how is thermal management inside the diode. Good quality diodes, have a Junction temp in between 6°C/W and 8°C/W. This means, that for each watt of consumption, inner temp inside the diode, will be between 6° and 8° more than the temp in the base of the led. When you have a lower quality led, this junction temp is bigger, and thermal effciency of the diode drops. This, among other things, is one of the facts that makes high quality leds give out a more powerful luminuos flux at same power consumption.
That 75% energy usage you tell, could it be like a base standard relation, when you are starting, and maybe when are things yet to be improved. But, if using the right spectrum, the right leds, having the optimal thermal management, the optimal layout, the optimal distribution and when everything is set up properly, i would say that leds are in the ratio of 2:1 comparing to HPS. This means, you could be getting same production using half the electrical power, or you could get twice your yield, using same amount of power. Of course, as i told, this will only come to reality when you have ALL the factors in optimal condition. Let's say a 0,6 g/W for HID, a 1,2 G/W for high quality well used leds as a standard. Of course, HID can be sqeezed more, but yet, those leds could also be more porductive bringing even 1,5 G/W... so as a standard figure i think, when you have propper set up, you can do 2:1 comparing to an HID lamp.
As you say, there is much risk in going for leds, and you could indeed end up with a panel not capable of doing it (outperform HID).... it is risky... nevertheless, it seems that if you do your reasearch and make a good pick, there is already panels available than will at least, boost up your yield between 50 and 70%, with expectations of even getting to a 100% boost. Or if you preffer savings, yo could be saving even half the electrical power.
You could also pick the right diodes and make your own DIY panel, and deliver this results also. I've seen homemade DIY set ups, delivering 1,2 G/W in their preliminary testings only. Yet to be improved.
And i try to be objective man... i am talking now, having results on my hand, not just speculation. I can tell that theres deffinetly a boost in production when using high quality leds, no doubt about it. The thing is to have an idea of how much this boost is. I'm telling you, 56W of leds, are giving me same amount of herb i've seen others pulling from a 150W HPS. Of course, 150W could be taken further under more experienced growers. But for the sake of statistics, lets then say, the 2:1 rule applies to these one, having my 56W results, comparable to the performance of an hypothetical 112W HID. So the way i see it, you have 2 ways of puting value to this better performance. You could think of it, as i'm getting same production of an 112W HID using 56W of power. Or you could think of it as if i was getting double the amountof herb, if using same amount of power in HID. Either way, Leds are already more efficient than HID lamps by quite a margin. It's just that as already said.. it is all about choosing the right combination, the propper layout and everything should be treated correctly. Ther are some things that have to be changed when switching to led. waterings jobs and nutrition schedule is different, since the leds wont evaporate wel the humidity on the soil. Also, the low heat, con affect rootdevelopment if the colds are tough.. So that's some things to consider among others.
Are they expenssive?, oh yes. Are they worth their money? i belive that when you go for the right ones, yes they are. In 5 years, you would be saving like 250 dollars only by not having to replace Bulbs. Add to that the lower electrical bill, or the higher yield you could be getting, and it is my opinion, that in the long term, they end up paying for themselves.
Cheers man. Nice discussion. I also try to keep it objective, since the idea here, is to get a clear vision of what this is all about... that's why, to really know what's going on here.... i think you always have to go for the scientific backup. You can't say "this is better than yours because of years of R & D that had lead us into developing a more efficient light"... that is pure bla bla.... if you are going to state you have a better efficient light, you have to give raw data of why! are yours better than others. I belive, spectrum changes, can do a bit, but mostly, thermal management and diodes native efficiency are the most important facts that will pull a higher luminous flux from them. It isn't an easy subject... but i belive, with no doubts, they are the future. Imagine, they are already outperforming HID and they haven't yet come to full development, much left to do in that technology. HID's have already set their roof. It is only a matter of time. It took a while for people to change from cassetes to CD's... but eventually, when more good panels are delivered from manufacturers, and more people continue doing their own DIY prototypes... hopefully the bad reputation some scammers are giving to this tech, will come down, and real attributes of this technology will rise.
Cheers.
Personally I was too fkin paranoid about burning down my house with 2 HIDs in such a small room... So I was hoping that LEDs would cut it because I wasnt too keen on going back with the HIDs , well it turns out that was the best move for me ... more buds, more peace of mind
