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LED Growlights

Hey Everyone:

I know we have a sticky, albeit, an outdated sticky, on lighting, but I also know a number of you have been doing experiments with LED Growlights. I'm in the market for 4 feet worth of growlights and wanted to know how you compared them to, specifically, T5 lights.

Currently, I have 2 foot, 4 bulb T5 fixtures (I talk about here), but I was curious to know if anyone had used any combo T5/LED fixtures (specifically this one), or pure LED fixtures and what their experiences were. I understand LED bulbs are very pricey, so I will probably end up waiting a few years before upgrading my setup, but the long life and electricity cost reduction are attractive to me. Thoughts?
 
There is an aquarium store nearby, the fellow running it is using led lights and fixtures pretty much exclusively. To me it looks like he gets lots of coverage per bulb/emitter. They are all on hanging wire rigs. Anything with electricity above water I like something a bit more solid. Either way the set up charges would be I think he said about $40 to $60 an hour plus the gear. When I looked at ready to go gear in panels they were many hundreds or dollars. Then again, the info with my LED tv said it would cost about $7 a year to run. That is pretty seductive. Complicating things is no one around here carries such things. So I could not "shop" first.
 
Where to start....When I was researching how I wanted to redo my Ceph grow area I looked into LEDs and tried to figure out what you are now, let me tell you there is not a lot of info out there. Here is all the info from that build http://www.terraforums.com/forums/s...uild-a-Cephalotus-grow-space-would-love-input!, its been just under 2 months so far so I can't say what long term results will be but I've recently turn down the dimmers for all the LED bars to right around 50% power. I will likely reduce it to about 35-40% over the next year if everything works out like I think it will.

For further input as to why I think I will be reducing the power level of those bars, check out http://www.terraforums.com/forums/s...le-Short-Term-LED-Experiment-with-a-few-Cephs. If you want to play around with LEDs the kit from this thread is the way to go imo. For $23 + the cost of a heatsink (check the as-is heatsinks if your on a budget, the last one I had was $10 barely bent and I don't see the need to straighten it but I could if I wanted to with little effort) + focusing lenses ($1.25 X 4) + shipping you can get an easy to assemble 4 light setup to mess with and see for yourself. No soldering, very minimal wiring and low wattage (.75-1.25W per LED from the technical specs). Attaching the lenses is the hardest part and its not bad. First time it would probably take 30-90m depending on your comfort level with DIY stuff. It took me longer to mount the bar then it did to build the bar.

I was growing a Heli (with high temps for a Heli) under a single T5 bulb (older bulb over 10m old) photo here.

DSC_0866 by randallsimpson, on Flickr

I moved it over to this experiment http://www.terraforums.com/forums/s...ium-I-m-Trying-It!-Thermoelectric-Cooling-Fun! around 2 weeks ago. This chiller is being lit by one of those moonlight kits with white LEDs. Under the low wattage kits it has been taking a few weeks to a month so far to get good color changes, under the Ceph LED bars its a week or two and there is clearly signs of plant burn (caused from moving them from lower light to high light without an adaption stage) photos on page 6 of that thread.

DSC_1077 by randallsimpson, on Flickr

I know I'm not compairing apples to apples, an old T5 bulb is no where near as good as a new one but I am seeing very dramatic results moving plants from the older T5 bulbs to the low powered LED (low power applied to them NOT low wattage, these LEDs can provide a ton of light if powered and I have no experiences with the lower wattage ones) Another selling point for these kits, if you like them and want to see what there full potential is you just need to get the larger driver and dimmer if you want one (I will always have a dimmer) and go.

Now to contradict everything I just wrote, I'm in the planning stages to rebuild my Lowland Nep area and I may end up using T5s for the added heat, if I went with LEDs I would either have to turn them up so high I think they would burn the leaves or the house down or I'd have to duct in a heater. LEDs can get VERY hot (way hotter than T5s) but I would never operate them at those levels. From everything I've read lower heat = longer life.

Basically its too early for me to give an meaningful information, but if I was to recommend something. Buy one of the moonlight kits (make sure and include in the comments block for them to swap out the blue LEDs for another type) and see for yourself.

Two months ago I knew nothing about LEDs so feel free to ignore me :-D. I've been trying to get as much information about my experiences with these LEDs as I can out there since there is so little good info but I "may" be heading into a flare-up so I may not be able to post as much for a few months. Feel free to ask any questions thou it might take a while for me to get back to you. Good days and bad days.
 
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Thanks, RSS! I'm not sure I'm confident enough to build my own setup, as I'd also have to create something to suspend the lights from, which would almost certainly cost, in addition to the parts, about $100. (Note, although I liked to Amazon, some sites from California seem to have the same kit for $75-$100). Honestly, in my current set up, I was just planning on laying it across the top of the tank, in all likelihood.

Mostly, I just wondered about LEDs losing lumins over time. I know that all lights fade, but I don't believe T5s fade all that much. It's good to know that LEDs will also heat up the tank a bit, as I'm currently using the T5s to heat up the tank a bit during the day, along with an increase in the heat, to give me a ~20 change for my plants over the course of day-night. During the summer, I hope that the cool night air (no AC here, unfortunately), and the light during the day will have the same effect, since the tanks are no longer exposed to the sun.

I'll definitely consider getting some LEDs in the future, although I kinda want to wait for the price to come down a bit, since I can get a 4 bulb T5 unit with bulbs for ~$50. Definitely keep us updated on the experiment. And, maybe, you should write a new sticky for lighting, especially since the old one, if I recall correctly, mentions T12s, which are being phased out and really shouldn't be used.
 
Mostly, I just wondered about LEDs losing lumins over time. I know that all lights fade, but I don't believe T5s fade all that much. It's good to know that LEDs will also heat up the tank a bit, as I'm currently using the T5s to heat up the tank a bit during the day, along with an increase in the heat, to give me a ~20 change for my plants over the course of day-night. During the summer, I hope that the cool night air (no AC here, unfortunately), and the light during the day will have the same effect, since the tanks are no longer exposed to the sun.

I'll definitely consider getting some LEDs in the future, although I kinda want to wait for the price to come down a bit, since I can get a 4 bulb T5 unit with bulbs for ~$50. Definitely keep us updated on the experiment. And, maybe, you should write a new sticky for lighting, especially since the old one, if I recall correctly, mentions T12s, which are being phased out and really shouldn't be used.

All lights fade over time, from my reading the common #s for LEDs is they maintain 70% of there brightness over the listed life of the bulb. So if its a 50K bulb it starts at 100% and would be 85% at 25K hours and 70% around 50K then a much more drastic drop off until they burn out. Now all those technical data sheets quickly get over my head and hopefully someone with more knowledge will chime in. I do know from experience that T5s have a drastic drop in light over the first 6-8 months, if you have a large number of T5s and only swap out the bulbs when they burn out you may never notice this. But I have a few tanks with 1-2 T5(s) over them and I clearly see a difference when I change a burned out bulb with a new one. The single bulb tanks I have to be very careful as some of the more sensitive orchids will throw a huge fit if I change their light that much in a day.

The main issue with using LEDs for heating is that you need a heatsink for them to work properly and that means all that heat that should be heading toward your plants is actually getting stored/dissipated above your LEDs and if my reading is correct the more heat the more life of your LED your burning up. You could probably work something out with fans and whatnot but I'm still of the opinion that operating them that hot is not the best solution. I think when you get into the math you want lots of LEDs running at lower power, I'll try to explain why later when I get to the real costs of the T5s. I do really love T5s they were a massive improvement over T8/12s and allowed us to grow a much larger range of stuff but I fear they are misleading people and costing them a ton of money they are not even realizing they are paying.

As for price, IF all the information about LEDs is half correct your much better off replacing all your lighting with them RIGHT NOW! That said I can not verify even half of that information is correct :banana2:

So far 1 LED powered at around 1W per 6" (8 for a 48" area) is more light than a single 48" T5. The LED are spotlight and the T5 are bar lights so that must be considered. (I come to this conclusion from testing with the moonlight kits and plants moved from tanks with old/new T5 bulbs and the coloration differences once moved. Light measuring meters are mostly useless (they only measure visible spectrums not the spectrums the plants are using and red/blue spectrum would grow plants well but the meters would read as low light or the ones that would work are very expensive and impractical for us to own))

So 1.25W*8=10W max power for the LEDs vs 54W for the T5. (These #s are from the technical specs and were not measured so they may or may not be accurate) Over a year 10 hours a day it would be 36.5 KWhrs for the LED and 197.1 KWhrs for the T5. If I recall correctly its $.104 per KWhr for me, or atleast close to that. So it would be $3.80 to run the LED for a year and $20.50 to run the T5 for a year. During the FIRST year it would cost an additional $16.70 PER T5 to operate and I believe we have cheap power down here.

Running costs for that 4 bulb T5 would be $82 a year. If you replace the bulbs on burnout you would need to replace them 2.5 times before the LEDs needed replacement.

Running costs for 4 rows of LEDs would be $15.2 a year. Assuming the bulb life is correct nothing would need replacement.

Over the 13.7 year life of the LEDs if would cost $208.24 running costs before you needed to replace probably everything. Rough guess of $350-400 initial costs. I believe you could run 3 rows and it would still be more light than the 4 T5, but I have not set anything up to see. If that belief is true than the costs would be $156.18 with a guess of setup at $260-300.
Over the same time frame if would cost $1,123.4 and you would need to replace the bulbs 1.5 times. You "might" be able to find T5 bulbs in 14 years! $50 initial costs

Now you could get a real LED kit and run it about 35-45% power and use less LEDs but I have no way to compare the two.

For short term T5 is way better, once you hit a few years of use your wasting money assuming all this information out there is correct.

That 4 bulb fixture is an amazing deal, I paid close to that for each T5 fixture when I bought them years ago. All I can say is I've been amazed at the results I'm getting from such low power. I'm way more impressed with LEDs as a low power application than I am using LED to get massive dark colors off plants. Just thinking of all the plants I could grow with 1W of power is amazing.
 
RSS, thanks for letting me know about the light meters. I wondered that, but couldn't ever seem to get confirmation.

Alright, definitely gonna consider investing in LEDs as my collection expands/my T5s burn out. I figured that LEDs would mirror T5s in that, in a couple years, they would significantly drop in price. And, I think, that works out well for me, as, around that time, the T5s will hit the end of their 'less than LED cost.'

Thanks for all this info (and math!).
 
I got a power usage meter and ran some tests with my full Ceph bars, the moonlight kits, and 2 T5s; here are the results.

For the wattage used I used the number on the meter and then I rounded up one. So the actual usage would be between the two and I would need a much longer running time to pin it down but these are close enough for my needs.

Moonlight Kit 4 LEDs running for 12 hours read .06 KWhrs = 5-5.83W (1.25-1.46W per LED)
Ceph rack 28 LEDs dimmer set at about 50% running for 5 hours read .19 KWhrs = 38W-40W (1.36-1.43W per LED)
2 single bulb T5 fixtures running for 2 hours read .19 KWhrs. = 47.5-50W

I find it interesting that I "tuned" in the lighting level slightly above what the moonlight kits are set at.
 
Most likely a bit less per led as you must take the efficiency (of the power supply and led drivers) into account. Also with CFLs the ballast's efficiency.
 
The reading were from the plug side of the item being testing so they are accurate within the accuracy of the meter. Basically, this was the power used by the entire unit not an estimate. The drivers/LEDs were both included as one whole unit.
 
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