The myth of LED efficiency

[Schreff]

http://www.advancedaquarist.com/2010/2/aafeature2

Ty Sir!!! Im still hesitant with the whole LED thing... I guess I should just take the plunge and give them a shot. I mean isnt PAR what we are concerned with in our lights anyway?

 

[TheFishMan65]

That is my understanding. I am DIYing my own LED fixture and was shooting for 200 par on the bottom. Sound like it may be to much .

 

[Schreff]

Depending on how deep your tank is, you could reach that number.

 

[TheFishMan65]

75 gallon so 20 inches I think.

 

[jcolletteiii]

75 gallon so 20 inches I think.

Easily doable. You just need to use some lenses. They 'snap' right onto the emitters and are available in a wide variety of angles. If I was going to do another DIY on a deeper tank, I would order a few different angled lenses and test them all to see which worked best.

 

[Schreff]

I think im going to get a LED fixture or fixtures for my 55 FOWLR tank and put a cpl "cheap" frags in the tank.

 

[AngelAddict]

I have 500W of MH and no chiller.

I agree that LEDs will be the way to go, but not yet. There is too much unknown with spectrum/which bulbs/what watt/which makers/which optics/etc...etc.. These issues will be worked out in time, but for now, its a guessing game.

Your temps must be pretty high, I like to keep mine around 75 (yes reef too) and there's no way a typical halide setup could do That. Also how much evaporation are you losing? I add water maybe once a week, evaporation is minimal with an open top. Also the color spectrum has been solved, its called dimmers. I can have anything from a 10-20k with a flick of a switch. Sounds like LEDs beat out halides in every category.

To the OP, Stephen, as state You definitely need to do more research on LEDs, especially with par values and costs!!!

 

[Garage1217]

You are dead wrong on the AI fixtures just so you know. An AI fixture does not light 12x12 *LOL* With the optics / massive output they are designed to be placed high over a tank and produce coral bleaching par even when placed high. Very respectable units but pricey as mentioned, each module usually covers a 24x24 area very well when placed correctly. Also to note, you can turn the output of each AI fixture down drastically and still maintain outstanding par at depth which has been proven / tested by a legitimate member on this forum.

As for halides being more efficient.... Not so much. I chose fixtures without optics as I prefer my light source be placed very close to the waters surface. My two units cost me around $900 shipped and light my 90G perfectly / will light my 120 perfectly when I upgrade, with no desire to have anymore light.

Over a 10 hour photo period I am averaging exactly 211w after running the numbers. vs. a little over 500w with my halides.
- All SPS is doing excellent / in some cases better growth than with my halides
- Some corals have gained colors while others have remained unchanged "which is a good thing"
- Drastic savings in cooling come into play, but cannot be calculated exactly. I can now walk into my kitchen and it feels as cool as any other room in the house, before it always felt warm after the halides were on for a few hours.
- I can actually touch my led fixtures at any time, they are just barely warm to the touch. If I did the same with my halides, I would have nasty blisters in an instant. Also, no more accidentally burning the crap out of my arms when I reach into the tank
- I am running those horrid little 3w units mentioned haha, and not cree's either *LOL* I am running the proclaimed lesser semi leds + 30W monster units which are only on for a short time a day. They have been more than sufficient to grow SPS, LPS & Soft corals
- Color is spectacular when leds are balanced properly / look better than any of my 20K's I ran previously
- As mentioned above, my evap also went down close to 1/2 of what it was previously. No more 3-4 degree tank swings either.
- Do I dislike halides? Not at all, I still dig them and will probably use a 150w over the small tank I am building the wife as it is a budget build and I can buy a sunpod used for dirt. However for my main display reef lighting, I would never go back to halides or t5.

So quick recap on savings. I am saving cash in multiple ways... No more bulb replacements every year to year and a half "usually they crap out on me around the year mark", savings in electricity as the AC is not running near as hard, RODI filter savings of over 50% on my system and over 50% in electricity from my old halide setup. How in gods name is their a downside? If there is, I have not found it!

Also just for giggles, I thought I would mention a local store of ours here in Az which is run by some of what I consider to be the most knowledgeable guys in reefing... The store is lit by 100% led and this is NOT a small store. In fact it is the largest dedicated saltwater store I have been in that was not on the west coast. Walking in is simply spectacular. They are not even running high power leds and from what I was told, they are at about the 6 month mark for using these leds with perfect success with all species of coral. Their coral tanks are not small by any means either. In fact they are very impressive!

To make it short LEDS ARE NOT A MYTH PERIOD, they just might not be a smart choice for lighting huge areas like when growing plants.

 

[Stephen Keen]

Well the reason that I mentioned using 12 is b/c in the article that was posted Sanjay said that the light was very focused with the Aquaillumination fixture, from what I understood from that there would be a small footprint. OK so 12 is excessive but Aquaillumination does recommend 6 of these fixtures for a tank that size. Here is the link to the fixture they have for sale....for $4k. If AI thought that 3 of these fixtures would be sufficient they would sell 3 for a tank this size, obviously the price would be much less and more people would buy.

http://www.fishnreef.com/Lighting/A...-LED-Light-System-w/-Controller/prod_988.html

This is the product description...
LED light system complete with external controller, mounting legs, external power supply and active cooling system. Each 12" section consists of 24 LED lamps grouped into a bank of 8 lenses or pods each containing two 6500K Daylight LED lamps and one Blue LED lamp. Blue LED lamps peak at 460nm. Recommended Tank Width: up to 24". Recommended Tank Depth: up to 36" with carefully planned placement of corals. Power Consumption: up to 100W per 12". Warranty: 2 Year. (1 Year on Power Supply.)

I thought this was interesting...
Recommended Tank Depth: up to 36" with carefully planned placement of corals.

I thought this was very interesting....
Power Consumption: up to 100W per 12"
That means that this fixture draws 600 watts of power!!! And this is the fixture that Sanjay said performed well! AGAIN where are the energy savings! Please note that these guys are the professionals and know much more than ANY of us on these forums when it comes to LEDs, if they thought that 1/2 the amount of LEDs would perform well in a reef tank they would sell a 3 light fixture for a 72" tank. PLEASE NOTE THAT A 1000 WATT LUMATEK BALLAST USES 750 WATTS!!! Here's the deal, they are basing these figures off of old magnetic ballasts and are not considering the more efficienct digital ballasts that have been available for years

I know that 12 might seem excessive but I was running 1200 watts over a 175 and my corals LOVED it, if I were experimenting with LEDs I would have to go with a 12 light fixture (or (2) 6 lights). I want my lighting to be intense b/c I want my corals to grow as much as they can. My thinking is that whether you have 100 corals or one, or if you can grow them 1/4" a month or 1" a month, tank maintenance is still the same no matter what, it only costs more in electricity. But I never would have used these LEDs b/c with 12 I would be using more power (1500 watts) than the (3) 400 watts over my tank which was consuming about just under 1000 watts of power.

The info that I don't see is how much heat they produce. There should be a BTU rating posted if its such a low heat producing fixture...instead of 1/2 the heat....because they also say 1/2 the power which isn't true. If I were selling a fixture that made 50% less BTU I would have those specs all over my advertisements. BTW a 1000 light emits 3500 BTU of heat per hour.

I'm not sure how much better I can state my case than this.

 

[Stephen Keen]

OK lets say I agree that LEDs save energy, with cooling cost, arguable light energy savings, and bulb replacement of MH. How much a month can you actually save. My 175 tank uses about $40 worth of power a month at most. That's 1200 watts of MH lighting, 1/4 hp chiller, and all of the pumps. Lets say I agree that LEDs will save you 50% over MH, ok so you save $20 a month plus $5 a month in bulb replacement. I think that I'm being very generous with all of the figures in benefit of LEDs.

That's $300 woth of energy savings a year. The cost of the LED if bought and not homemade for a tank my size is $4k. It would take more than 10 years for this fixture to pay for itself. People say "I don't have to run a chiller", ok how is that a benefit? If you are purchasing expensive LEDs then you have the money to purchase a chiller and to pay for the energy usage for YEARS to run it and still spend less than with LEDs. LEDs are not an efficient way to spend your money either!

 

[TheFishMan65]

I posted this the other day, but maybe it got lost as the last post of the previous page. It has some heat info.

I had the opportunity to watch a seminar on "Designing for LED Luminaire Reliablity" by electronic design (seminar is available there), Bergquist, and Digi-Key.
The slides referred to Luxean and CREE (maybe more) so I am assuming the information is universal.
They had achart
.........Incan...Fluor...MH...LED
Visible....8%.....21%....27%..15-25%
IR........73%.....37%....17%...~0%
UV.........0%......0%....19%...0%
Total..
Radiant...81%.....58%....63%..15-25%
Energy.
Heat......19%.....42%....37%..75-85%
If i read this right MH and LED produce the same amount of light per watt. But because LEDs are directional and the wavelength can controlled they can produce more PAR than MH as has been pointed out.

The interesting thing is they produce more heat than any other method. But as mentioned it is not IR heat hitting the water, but heat from electric loss that must be taken away. But since you are using few watts is it 50% then the heat may be comparable to MH.

Also the governmental goal is to have LED increase to the 50% point by 2012. I also don't know what generation LEDs this chart refers to. LEDs have increase 30% in the last year (XR-E -> XP-G).

I hope this help it at least add some solid numbers (if they are current and correct - nobody questioned them).

 

[mcallahan]

Your temps must be pretty high, I like to keep mine around 75 (yes reef too) and there's no way a typical halide setup could do That. Also how much evaporation are you losing? I add water maybe once a week, evaporation is minimal with an open top. Also the color spectrum has been solved, its called dimmers. I can have anything from a 10-20k with a flick of a switch. Sounds like LEDs beat out halides in every category.

To the OP, Stephen, as state You definitely need to do more research on LEDs, especially with par values and costs!!!

Temp goes from 77.7 to 78.3.

Evaporation is about 1.5 gallons/day. Why is this an issue? With an ATO, your params stay stable and water is WAY cheap.

I guess this could be a new way to brag... "My SPS grows an inch a day!", "Oh yeah, well I only evaporate .04579 gallons of water a day!"

You can make your lights a different color (viewable with the eye) with dimmer, but that has nothing to do with what we are talking about. We're talking about the whole range of colors put off by the light, including some we can't see. E.g. a light that looks white to the naked eye can put out a lot of color in a certain spectrum (red/blue/green) and you can't tell by looking at the bulb. So just because the bulb can turn blue, that isn't a great indicator of the spectrum put out by the bulb.

 

[Garage1217]

You also just admitted LEDs are more efficient *LOL*

Ok lets get to the numbers on a system and what you could potentially save since I am a specialist in tank efficiency I have no idea what your tank dimensions are so lets go with a nice sized standard 180G long tank at 72 x 24 x 25 Tall for a comparison.

Us average is 11 cents per KWH
At 1200W over a 10 hour photo period your current lights run you
- $40.14 a month
- $481.80 a year

A nice budget system such as a pair of maxspect g2 230w units would cost you $1740 shipped and provide excellent light for the tank mentioned above. So at the face value / maximum wattage drawn "actual wattage will be less depending on how you setup your light schedule / example mine draw 211w but are rated at 320w" of 460w you will pay the following.
- $15.39 a month
- $184.69 a year

Right away that equals a savings of $297.11 per year and would take 5.85 years for the ROI

Now lets step into the real world if you are replacing equipment you already own
- You can sell your current 1200w worth of halides which I assume equals a 3qty of 400W halides with ballasts "as no one in reefing uses 600w units really" reflectors & bulbs for a low cost of at least $600 for all three sets combined unless they are junk. Now lets take the $600 off of the $1740 investment cost and we have $1140. Now your ROI is 3.83 years.

Now lets further the calculations / NOT including the savings in cooling costs on the house which can be drastic with 1200W worth of halides running in the summer and not include the savings on your chiller not having to work hard which is NOT cheap to cool 175 gallons. Lets just talk about bulbs.
- 400W bulbs on a 1 year replacement schedule for 3 400W units, you are looking at $90 a pop for a good set of SE 400w bulbs like radiums. So $270 per year in bulbs / $22.50 a month. For a proper calculation for payoff during the warranty period of the LED units, we would go by the manufacturers warranty period of 18 months which is the minimum life expected out of the LED product by the manufacturer. 18 months x $22.50 a month average bulb cost and you are at $405.00 worth of bulbs. Now take the $405 off the $1140 initial investment and we are at $735.00 initial investment.

So not even taking into consideration ALL of the savings factors, ROI is now 2.5 years maximum. Again not counting the drastic savings in
- Cooling the home
- Chiller operational costs if you run one
- Cost of additional RODI water from evap





Now, as I am sure this argument will come up, lets look at NEW vs NEW cost comparison / out of the box cost for 1 year of usage without any replacements.
- The LED lights I mentioned $1740.00 + $184.69 in electricity = $1924.69 for the first year

Quality Halide setup
- 3 qty of quality reflectors, lets go with hamilton cozumel suns $169.95 + $40 shipping = $549.85 for the 3 shipped
- 3 qty of quality ballasts, lets go with lumatek $140.00ea + $5ea per connector $435.00 + $30 shipping so $465 for the 3 shipped
- 3qty of quality bulbs $90ea + $15 shipping = $285 shipped for the 3
- 3qty of quality timers $20ea = $60 / can be had at home depot
- Moonlight setup for the tank $80 to cover the large span
Total $1439.85 + $481.80 in electricity for the first year = $1921.65 cost for the 1st year with no replacement bulbs included.

A difference of around $3.04 for this example between the two setups brand new out of the box which will both light the 180 very well/

Now if I want to bash your thought process a little more, lets add in bulb replacements to run for year 2 at $285 shipped & calculate the electricity savings for the 2nd year of use and you just saved $579.07 over a new quality halide setup, minus the $3.04 difference by the end of year two

Yes I understand there are endless comparisons possible with tank sizes and ways you can light them. This is was just a standard comparison of a popular sized tank to get the point across that your title post of "The myth of LED efficiency" is utterly ridiculous. I can run these numbers all day with common tank sizes.

Some food for thought.

OK lets say I agree that LEDs save energy, with cooling cost, arguable light energy savings, and bulb replacement of MH. How much a month can you actually save. My 175 tank uses about $40 worth of power a month at most. That's 1200 watts of MH lighting, 1/4 hp chiller, and all of the pumps. Lets say I agree that LEDs will save you 50% over MH, ok so you save $20 a month plus $5 a month in bulb replacement. I think that I'm being very generous with all of the figures in benefit of LEDs.

That's $300 woth of energy savings a year. The cost of the LED if bought and not homemade for a tank my size is $4k. It would take more than 10 years for this fixture to pay for itself. People say "I don't have to run a chiller", ok how is that a benefit? If you are purchasing expensive LEDs then you have the money to purchase a chiller and to pay for the energy usage for YEARS to run it and still spend less than with LEDs. LEDs are not an efficient way to spend your money either!

 

[jcolletteiii]

OK so 12 is excessive but Aquaillumination does recommend 6 of these fixtures for a tank that size.

AI gives guidelines and recommendations. I will be running only 4 of the NEW modules over my 6 foot 135. The modules will be placed high enough that the footprint will completely cover the bottom.

http://www.fishnreef.com/Lighting/A...-LED-Light-System-w/-Controller/prod_988.html

This is the product description...
LED light system complete with external controller, mounting legs, external power supply and active cooling system. Each 12" section consists of 24 LED lamps grouped into a bank of 8 lenses or pods each containing two 6500K Daylight LED lamps and one Blue LED lamp. Blue LED lamps peak at 460nm. Recommended Tank Width: up to 24". Recommended Tank Depth: up to 36" with carefully planned placement of corals. Power Consumption: up to 100W per 12". Warranty: 2 Year. (1 Year on Power Supply.)

I thought this was interesting...
Recommended Tank Depth: up to 36" with carefully planned placement of corals.

I thought this was very interesting....
Power Consumption: up to 100W per 12"
That means that this fixture draws 600 watts of power!!! And this is the fixture that Sanjay said performed well! AGAIN where are the energy savings! Please note that these guys are the professionals and know much more than ANY of us on these forums when it comes to LEDs, if they thought that 1/2 the amount of LEDs would perform well in a reef tank they would sell a 3 light fixture for a 72" tank. PLEASE NOTE THAT A 1000 WATT LUMATEK BALLAST USES 750 WATTS!!! Here's the deal, they are basing these figures off of old magnetic ballasts and are not considering the more efficienct digital ballasts that have been available for years

These are the OLD AI modules. They use an older gen emitter. The new modules are slightly less expensive, and only draw 74 watts as I have told you already. Which, again totals 444w, which again, is significantly less than 750w. And... yes again... most people run these AI units at reduced wattages becasue they are TOO BRIGHT. I currently run mine at 20% white, 40% blue. This means that of the 74w each unit consumes at 100% power, I am currently only using 9.8w from the white LEDs and 9.8w from the blue LEDs for a grand total of 19w from each of my modules. Let me reiterate this point: almost no one runs these units at 100%white 100%blue, so the power draw can be significantly less than 444w for a 6 foot unit.

 

[jcolletteiii]

Here's his other thread at Austin Reef Club.

http://www.austinreefclub.com/topic/12598-the-myth-of-led-efficiency/page__st__40

 

[Beaun]

You keep comparing the AI unit to Mh lights when there are so many other fixtures out there. The Acan Lighting A102 or Eco-Lamps KR92 run with significantly less power consumption while keeping their PAR sufficiently high enough for any corals. If you were to run two 36" A102's (KR92's) accross a 6' tank you would still only be running at 300W of power. That is only if you are running them at 100% all the time. People have problems with bleaching with running these fixtures at 100% for too long. 300W max of power consumption for a 6' tank is not too bad.

Also, what about the initial cost of a chiller to begin with, you are talking about $1,000 to simply purchase a new chiller and then the cost to run it. Two 36" A102s will cost $3,600, take away the chiller and you are down to $2,600. Lets say your 400w ballasts are $150 and the reflectors are $120; that is $810 on just an initial set up. Then you need three 400w bulbs at ~$90 each, thats another $270; $1080 total. Then we need to buy bulbs at least once a year so that is another $270 a year. With the cost of a MH set up and a chiller the price difference to the A102 is $1520. If we take your $300 in power savings a year and add in the $270 a year (minimum) for bulbs we have $570 a year. We pay off our more expensive lights in ~3 years, not too bad.

Please, check my math and my logic, but it seems to make sense to me and I'm a T5 guy so I have no vested interest in this.

 

[docstomper]

Dont lie to yourself everyone. If you bought new LED's, you are probably going to change your lights in 3-4 years anyways. Lets face it. Everyone is going to be able to justify spending any ridiculous amounts of money on "New" fixture that is better than the one you have. So even if it does pay itself off in 4 years who cares!?

If I had bought Metal Halide setup lets say used... (Doubt your going to find a used LED setup) for 600 dollars for (3) 400 Watt MH with new bulbs for 90 dollars a pop we are at 900 bucks. THEN. I took the extra money and invested it in stocks... Now it pays for itself.

I win. t5's RULE!

Dont judge my math.

 

[mcallahan]

Dont lie to yourself everyone. If you bought new LED's, you are probably going to change your lights in 3-4 years anyways. Lets face it. Everyone is going to be able to justify spending any ridiculous amounts of money on "New" fixture that is better than the one you have. So even if it does pay itself off in 4 years who cares!

Very true! Reef keepers are truly junkies...they have to have their fix constantly and when the latest greatest comes out, they'll move heaven and earth to have it.

So saying your LEDs will last for 7-10 yrs is nice, but not significant.

 

[docstomper]

Yes. That about wraps it up lol.

Buddy I know put in SoloTubes in his house because it was going to save him X amount of dollars a month. Chiller runs less, no electricity for MH ect. Said he would save about 120 a month.

After a month or so I go back over to his house... He now has his MH over his sump/frag tank connected to the same main display. Lol.

All in all.. No one is really saving any money. They just want a reason to justify the hobby. This is why I love it.

 

[boodlefish]

If I had bought Metal Halide setup lets say used... (Doubt your going to find a used LED setup) for 600 dollars for (3) 400 Watt MH with new bulbs for 90 dollars a pop we are at 900 bucks. THEN. I took the extra money and invested it in stocks... Now it pays for itself.

I win. t5's RULE!

Dont judge my math.

:rolleye1: yeah as the DOW drops another umpteen points... or some hedge fund manager shorts your stock and by the end of the month that NEW MH setup is listed in your "getting out thread"

I do like my T5's... but am interested in LED's too.