# Lithonia T8 and LED 1x4 wraparound. side-by-side performace comparison



## Electric_Light (Apr 6, 2010)

This thread compares the Lithonia 1x4 wrap-around fixtures in the LED version LBL4 LP840 and the T8 version LB232 MV. They're nearly the same and are both current production luminaires. 1x4 wrap around with a curved K12 diffuser 10" width by 48" length and 3" height surface mount. The photometric distribution of these two units are similar. Both rated for 120-277v. 

Every day, LEDs are getting needlessly specified and driving up cost. This will hopeful be an eye opener. 

LBL4 LP840, LED version costs $120 and uses permanently installed LED strips. 

http://www.acuitybrandslighting.com/library//ll/documents/specsheets/curved basket wraps.pdf

LB232 MV T8. Priced at about $60 and it has a CEE1 NEMA Premium T8 ballast. 

http://www.acuitybrandslighting.com/library//ll/documents/specsheets/led-wraparound.pdf

LED version is rated at 4,000 initial lumens with 50W power consumption.
The rated life is 50,000 hours to L70, or until 30% of initial output is lost. 
At the end of life, you're down to 2,800 lumens and efficacy of 56LPW. For the mean lumen, I chose 3,400 lumen and efficacy of 68 LPW. These are the mid values between new vs end of life values. 

T8 version ships with a NEMA Premium ballast. The optical efficiency of fixture is rated at 89.1%. Using data for Advance ICN-2P32-N ballast, the fixture will deliver initial output of 3930 lm(maintained 3815 lm) when you use a set of F32T8/25W/ADV841/2XL lamps rated at 68,000 hr rated. Input power is 45W. This provides the best match to LED in terms of maintained lumens. 

(28W lamps, you get 4,110 maintained lumens @ 48W input
if you use RE80 premium 32W lamps, you get 4,750 maintained lumen @ 56W input)

The 68K hr T8s are $6.10 ea. 

All my calculations factor include losses in fixture. 
LED fared worse in every way. The T8 maintains nearly the same output throughout useful life. T8 maintains 85 lumens per watt nearly the entire time. LED ito 68LPW after 25,000 hrs(my midpoint guess) and 56LPW at 50,000 hrs(manufacturer's data). T8 starts off 8% more efficient and finishes 50% more efficient. The widening gap is due to crude standards used for LEDs allowing 30% loss of output for the definition of lifetime. 


T8 = $72($60 + $12 for two lamps) for fixture providing 3,815 mean lumen(3,930 initial)@ 85LPW after about 25,000 hrs of use. Power use is 45W. 

LED = $120, only providing estimated 3,400 mean lumen(4,000 initial) at 68 LPW at about the same 25,000 hrs point. Power use is 50W. 

My calculation factors in both fixture loss and lamp depreciation. I did not factor in dust as they both experience dust/insect related fouling nearly the same way. 

68,000 hr lamps can make it to about 48,000 hrs while keeping lamp failures to 10%. It wouldn't lose 30% output like LEDs

So, I conclude here that buying LBL4 LP400 LED provide worse efficiency (LPW), higher watt usage, lower sustained delivered lumen compared to LB232 MV, the T8 counterpart used with best 48" 25W T8 lamps and maintenance interval that is comparable. 

The real kicker is that you pay nearly 70% more for the privilege of having a worse performing product. Yes, I did factor for higher cost of 68K hr lamps in pricing. 

You can come up with substantial maintenance savings in favor of LEDs... if you used 15,000-18,000 hour rated for earlier T8 lamps from the early 1990s :laughing: Only LED lamp sales people would do that. 

*
Photometrics: *
Left half is LED, right half is T8
The lumen for T8 for this standardized testing assumes 2950 lumen lamps operated at 1.0 BF. My configuration runs 25W 2400 lumen lamps at 0.92BF. 









Top half is T8, bottom half is LED









You can see that these two particular LED and T8 fixtures have virtually the same photometric performance. I am comparing two alike fixtures. Not two fixtures with substantially different patterns.


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## Electric_Light (Apr 6, 2010)

Your old T8 fixture is probably drawing 59W and delivering 4750 lumens on 700 series lamps at the lamps and the tired old fixture may only be delivering 60-70% giving you 3,300 lumens from a 1x4 two lamp 32W T8 system. It has more to do with how degraded the reflective paint and the diffuser are than anything else. 

When you replace them with LED fixtures that put out 4,000 lumens out of the box, it will give a good impression, but in about 3 years of around the clock use, the LEDs drop to the same level. This does give you a 15% kWh saving for the3 same use, because the LED version is 50W which is 15% lower than 59W of old T8 system using 32W lamps. This cause a false attribution that saving is due to "LED technology". 

Even if the material cost was the same, the LED version is the inferior performer. In this case, LED version costs more, a lot more.. 70% more... and performs *worse *

Lighting sales most likely did not present the superior alternative on the table to select from which is the premium T8 set up which costs 40% less in materials and performs better all the way around. In this particular example, the Premium 25W T8 setup results in 24% kWh savings assuming the same burn time surpassing the 15% saving offered by the more expensive inferior performing LED option. The long term lumen performance is also expected to be better for T8. T8 performance is predictable. LED's long term decay stability is not at this point.


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## Texas_LED_Guru (Mar 1, 2013)

That's all fine & dandy, but LED technology changes for the better every year & in lots of cases every few months.

Florescent light bulbs will continue to have their place, but their performance & potential has been maxed out with the introduction of triphosphors & high efficiency electronic ballasts.

You can only do so much to improve a centuries old technology. LED's are still in their infancy in comparison.

OLED's & nanotechnology in LED's is the future. You either hop on board or get left in the phosphor powder dust.

Not to mention the very thought of the word *mercury* scares the hell out of most people.


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## MTW (Aug 28, 2013)

Texas_LED_Guru said:


> That's all fine & dandy, but LED technology changes for the better every year & in lots of cases every few months.
> 
> Florescent light bulbs will continue to have their place, but their performance & potential has been maxed out with the introduction of triphosphors & high efficiency electronic ballasts.
> 
> ...


LED is still a pile of garbage.


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## Texas_LED_Guru (Mar 1, 2013)

MTW said:


> LED is still a pile of garbage.


If its good enough for the Empire State Building in New York, New Years Ball, Golden Gate Bridge in San Francisco, Space Needle in Seattle, CN Tower in Toronto, & Vatican in Rome its good enough for me...

Now, most recently, Rab relit the Hoover Dam.

Carry on old timer...

https://www.rabweb.com/led-300-watt-floodlight-fxled.php


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## Going_Commando (Oct 1, 2011)

Meh, we should just go 100% back to incandescents. All this new fangled stuff is garbage, and all doomed to failure, and will escort in the extinction of the human race. Obviously we are at the pinnacle of lighting technology, right now, in 2015.


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## Electric_Light (Apr 6, 2010)

Going_Commando said:


> Meh, we should just go 100% back to incandescents. All this new fangled stuff is garbage, and all doomed to failure, and will escort in the extinction of the human race. Obviously we are at the pinnacle of lighting technology, right now, in 2015.


Did you read the first post? 
The price is higher
performance is poorer or higher
durability of solid state fluorescent LED is lower than low pressure mercury gas discharge fluorescent.


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## Moonshot180 (Apr 1, 2012)

I appreciate the knowledge base here on the subject regarding LEDs. The thread where you brought up the LED drivers, and how they are usually cheap and emit crappy light was a good read.


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