LED's vs. T12, T8, or T5

[steve66]

I just had a rep show me the Lithonia IBG high bay fixture.

180 delivered lumens per watt.

And its rated to have 88% initial output after 60,000 hours and 70% after 100,000 hours.

Also rated for 130 deg F ambient temp.

I priced a 12,000 lumen version and it was about $200.

To compare that with fluorescent, start with a 3000 lumen T8 lamp that uses about 30 watts. That's only 100 lumens/watt. But it will also loose some light output with the fixtures optic losses. And it will also require more than 30 watts in due to the ballast losses. So fluorescent will be more like 80 lumens per watt.

That makes the LED fixture more than twice as efficient. And LED will only get better.

 

[peter d]

I just had a rep show me the Lithonia IBG high bay fixture.

180 delivered lumens per watt.

And its rated to have 88% initial output after 60,000 hours and 70% after 100,000 hours.

Also rated for 130 deg F ambient temp.

I priced a 12,000 lumen version and it was about $200.

To compare that with fluorescent, start with a 3000 lumen T8 lamp that uses about 30 watts. That's only 100 lumens/watt. But it will also loose some light output with the fixtures optic losses. And it will also require more than 30 watts in due to the ballast losses. So fluorescent will be more like 80 lumens per watt.

That makes the LED fixture more than twice as efficient. And LED will only get better.

That's the bottom line. I said this in another thread recently, but CFL, linear fluorescent, and HID are all dead technologies now. I joked that the engineering department at the lighting and ballast manufacturers for those technologies are one lonely desk over in a dark corner somewhere. All R&D resources are going into developing LED technologies now and it's the future. I'm sure the manufacturers will continue to make replacement parts for obsolete technology for the time being, but there is certainly no effort being put into making them better.

 

[MNSparky]

That's the bottom line. I said this in another thread recently, but CFL, linear fluorescent, and HID are all dead technologies now. I joked that the engineering department at the lighting and ballast manufacturers for those technologies are one lonely desk over in a dark corner somewhere. All R&D resources are going into developing LED technologies now and it's the future. I'm sure the manufacturers will continue to make replacement parts for obsolete technology for the time being, but there is certainly no effort being put into making them better.

I agree with Tim. I'm impressed with the LED products I've been using lately and see them only getting better while the others he mentioned are staying stagnant. The supply houses are even starting to shy away from selling them. With the rebates offered by the POCO these days, it doesn't pay to install a large fluorescent project anymore.

 

[peter d]

I agree with Tim. I'm impressed with the LED products I've been using lately and see them only getting better while the others he mentioned are staying stagnant. The supply houses are even starting to shy away from selling them. With the rebates offered by the POCO these days, it doesn't pay to install a large fluorescent project anymore.

Thanks Chris. :thumbsup:

 

[Electric-Light]

I just had a rep show me the Lithonia IBG high bay fixture.
180 delivered lumens per watt.
And its rated to have 88% initial output after 60,000 hours and 70% after 100,000 hours.
Also rated for 130 deg F ambient temp.
I priced a 12,000 lumen version and it was about $200.

Pretty neat. What's the exact model number? I am wondering if it is 130F, AND L88 60,000 hrs AND 180 LPW all at once.
I have to look into the warranty terms if it says it's not warranty issue until light drops to under 70% regardless of age. Recently, I noticed they started saying "lumen compensation" instead of "lumen management".

Anyone know if they're still using solid state fluorescent technology with blue driven phosphor or if they're using multiple colored LEDs?

To compare that with fluorescent, start with a 3000 lumen T8 lamp that uses about 30 watts. That's only 100 lumens/watt. But it will also loose some light output with the fixtures optic losses. And it will also require more than 30 watts in due to the ballast losses. So fluorescent will be more like 80 lumens per watt.

The current limit on traditional fluorescent lamps is around 105 LPW including ballast. There are some specular optics breaking 90%, so I'd guess the ~100 LPW is the ceiling for now.

That's the bottom line. I said this in another thread recently, but CFL, linear fluorescent, and HID are all dead technologies now. I joked that the engineering department at the lighting and ballast manufacturers for those technologies are one lonely desk over in a dark corner somewhere. All R&D resources are going into developing LED technologies now and it's the future. I'm sure the manufacturers will continue to make replacement parts for obsolete technology for the time being, but there is certainly no effort being put into making them better.

LED ballasts and fluorescent ballasts are very similar and they are pretty close to technical limits with the most efficient ones reaching around 95%. There are plenty of 70-80% models out there though

 

[steve66]

Its the Lithonia IBG.

 

[Electric-Light]

Its the Lithonia IBG.

That is the product line. There are many options within the line. Such as CRI, CCT and HEF (high eff) and some all combination might not be available, for example 3000K, 90 CRI and HEF together. So again, my question is, is the $200 for the one with the HEF option added?

If the light elements use something other than the standard blue LED + yellow phosphor solid state fluorescent technology, the 180 LPW option can be a VERY expensive option, like to the point where you might LOSE hundreds per fixture if you were to bid assuming your cost per fixture is $200.

Because of confusions like this, it's not a bad idea for owner and utility representative to thoroughly inspect LED fixtures to avoid mistakes and unauthorized substitution. Confirm the paperwork and fixture label match exactly and verify that fixtures have all the options required in specifications and incentive qualification. If you wait until the final payment has been made to discover the mistake, it increases your frustration level in getting resolution, which means making them remove and redo everything.

 

[steve66]

That is the product line. There are many options within the line. Such as CRI, CCT and HEF (high eff) and some all combination might not be available, for example 3000K, 90 CRI and HEF together. So again, my question is, is the $200 for the one with the HEF option added?

If the light elements use something other than the standard blue LED + yellow phosphor solid state fluorescent technology, the 180 LPW option can be a VERY expensive option, like to the point where you might LOSE hundreds per fixture if you were to bid assuming your cost per fixture is $200.

Because of confusions like this, it's not a bad idea for owner and utility representative to thoroughly inspect LED fixtures to avoid mistakes and unauthorized substitution. Confirm the paperwork and fixture label match exactly and verify that fixtures have all the options required in specifications and incentive qualification. If you wait until the final payment has been made to discover the mistake, it increases your frustration level in getting resolution, which means making them remove and redo everything.

It's about a $25 difference for a 12,000 lumen fixture. With a frosted lens, the difference is basically 140 Lumens/watt vs. 170 lumens per watt.

I would assume they have the standard efficiency for when every dollar matters or when they are competing with other manufacturers who have cheaper products. And they have the high efficiency option for times when engineers write specs that say things like "Must be 150 lumens per watt or better."

 

[Electric-Light]

Pretty damn close equivalency compared:This is how you make the A vs B comparison
I am comparing LED and 6 lamp T8 HBF with 28W HPT8 that ends up giving you around 16,000 delivered lumens with L90 of about 60,000 hrs.

Reference I used for the LED:
http://www.acuitybrandslighting.com/Library//LL/DOCUMENTS/SPECSHEETS/IBG.PDF

Look at "comparable light sources" column. You may notice that equivalency reference is much more reasonable and is far less bloated than it was years ago. Some of you may also notice that they started using "lumen compensation" instead of solely using "lumen management" in reference to nLight N80 option that maintains the same output by adjusting the dimming ballast to increase power consumption according to the pre-defined LED degradation curve and power-on hours to cancel out the effect of cumulative LED degradation. Once the 25% reserve power is maxed out, it runs at the full power and continue on by losing light output as LEDs lose output.

When it was freshly introduced,Lumen Management

More recently, Lumen Compensation


Fluorescent: 16,500 LM per 188W @ 277v $106.24

Lithonia IB 632 188w. Ballast and lamp together makes light at 95 LPW
The fixture is 92.3-92.7% efficient. This brings you 16,500 delivered lumen using 188W. which is 88 LPW

Fixture is $70 @ homedepot.com (current price, 20% special in place)
$36.24 @ $6.04/ lamp PHILLIPS 28W 2XL ADV841 ~60,000hr-90,000 hr lamp (L92) (HDSUPPLY)

LED: 16,000 LM per 112W @277v $385 60,000hr (L88)


IBG 18000LM SEF AFL GND MVOLT OZ10*** 40K 80CRI DWH IBG 18L MVOLT
The stock option 18,000LM fixture. The "HEF" appears to be made to order. I am not sure how much the HEF option adds. It could be disproportionately high like the top of the line CPU vs a notch or two down. I assume that the fact it's not standard stock item means it's not going to sell well enough to justify ongoing production.

$385, also homedepot.com
16,000 delivered per 112W @ 143 LPW (per Acuity spec sheet)

*** if utilized, it incurs 0-10v wiring, controls, and setup expense, because it is not already in place for the existing 175W MH
The amount of account discount is probably not the same between the highly fluid LED vs pretty much non-changing T8, so let's just use public portal pricing.

Incremental cost per fixture: $278/fixture
Power reduction/fixture: 0.076kW
demand saving per fixture $10.944/year/fixture at $12/kW
Industrial energy rate for facilities that use these lights like 8-10c/kWh in high priced area?

665.76kWh/year difference if 24/7
You need 3,089 kWh to get $278 back @ 9c/kWh. Simple Payback Method.

You can make money by charging a fee to lend money. You have to pay a higher fee to borrow money. The difference goes to the bank's pocket. If you assume you can borrow the additional $278 needed for LED option for no charge, it takes 4.63 years @9c/kWh to break-even. I'm going to ignore the $10.94/year demand saving estimate in exchange.

 

[steve66]

My post was simply to point out that LED is very efficient.

I think you have claimed many times that it is not any more efficient than high quality T8 lamps. Even if that were true 6 months ago, my point is its not true any more, and will be even less true 6 months from now.

Now you seem to have switched to a payback analysis. I never claimed that the LED fixture would have any particular payback, just that its very efficient, and at a price that doesn't cause sticker shock.

The N80 is a great option and it prevents designers from having to over light a space from the start to compensate for what the fixture is going to look like a few years down the road. It alone can provide 20% in energy savings from Day 1. Yet you keep painting it in a bad light.

The N80 is an option - if you think its a bad option, don't spec it.

 

[Electric-Light]

I just had a rep show me the Lithonia IBG high bay fixture.
180 delivered lumens per watt.

I'd like the see the quoted price along with the entire long model number with all the options and the terms of the quoted price. (was it for 1,000 + units?, before, after, whatever incentives? ) If you don't want to post it, you could PM me.

My post was simply to point out that LED is very efficient.
I think you have claimed many times that it is not any more efficient than high quality T8 lamps. Even if that were true 6 months ago, my point is its not true any more, and will be even less true 6 months from now.

I didn't say LED can never surpass the LM/W of fluorescent.

Now you seem to have switched to a payback analysis. I never claimed that the LED fixture would have any particular payback, just that its very efficient, and at a price that doesn't cause sticker shock.

I didn't say you claimed anything about payback. I put payback analysis here, because I feel that cost analysis is relevant.
Cost is usually the primary motivation. You wouldn't have dropped a price if it was irrelevant. I was a bit concerned you didn't even list HEF option when I asked about the model.

The N80 is a great option and it prevents designers from having to over light a space from the start to compensate for what the fixture is going to look like a few years down the road. It alone can provide 20% in energy savings from Day 1. Yet you keep painting it in a bad light.
The N80 is an option - if you think its a bad option, don't spec it.

I wouldn't say I am painting it in bad light. Rather I am laying it out in engineering perspective and actual technical reason for why it was used.
I am just heavily criticizing the indirect double speak marketing spiel that is confusing. My feeling on this is that it has done nothing but create confusion among field personnel, customers, incentive program administrators and policymakers who do not have technical expertise. Just from what I have seen in the way people talk about N80 here, there is clear sign that some are not actually understanding of what it does, why it's there and how it works. Manufacturer sponsored training was probably a big influence on how they were taught.

The clock in your car console or stereo is temperature compensated. This isn't something marketing people chose to talk about or even mention it, but if they did they wouldn't talk about it the same way I do. Technical explanation is that extreme temperature range experienced inside parked cars cause enough drift in the time reference to cause objectionable amounts of deviation and compensation is used to offset this. There's always exceptions, but you ever notice car clock usually keeps time good enough that you don't notice any drift between your standard/savings time changes?

Your wrist watch don't see the same amount or duration of extreme environment and do not suffer enough drift to cause objectionable deviation.

So the real reason is that LED suffers enough degradation for them to implement compensation option while fluorescent do not.

I am also deeply criticizing the double standard that gives leniency to LEDs and discretely comparing against existing system in a way that do not follow general lighting practice. This practice is far more pervasive in the retrofit industry than actual lighting design.

So if the space is used for the same purpose the existing fixtures were installed for, the original design may have used a target level

General industry practice for LED life is estimated run time for LEDs to degrade to 70% output.

LED, General purpose metal halide, mercury vapor lamp, high power density fluorescent (induction CFL, VHO sign lamps) are the only things that lose 30% or more before they burn out. We have enough capabilities to apply degradation compensation to any one of them over a limited range. The limitation is the upper and lower power limits to avoid lamp life reduction or damage. Did you know General Electric once sold an eHID ballast for traditional 175, 330 & 400W MH that looks like a saucer? It looks like a saucer and sits above the HID bell jar and did exactly what N80 does. I have never seen one in person, and it didn't stay in catalog for long.

I just had a rep show me the Lithonia IBG high bay fixture.

That makes the LED fixture more than twice as efficient. And LED will only get better.

I have also seen back pedaling. Some performance parameters is getting taken off compared to the best that was available several years ago, such as long term durability and flicker performance in the interest of BOM cost. When LEDs first started picking fights with fluorescent, companies like CREE claimed fluorescent as inadequate dimming and flickering when in reality their products had more flicker content than what they were criticizing. R9 deep red rendition was a big deal at one time.

Now many LEDs have receded to 80 CRI and R9 value in single figure if it's even made publicly available. Over the last decade or so T8 RE80 lamps have been available in CRI of 80-86. Now the shortest rated life LED bulbs are only 12,000 to 15,000 hrs to 30% degradation.