LED vs hi power CFL high bay lights

howdy,

i am building a shop that is 65x70 that will have 18' height for lighting.

i thought at first i would use metal halide high bays, but they are not instant on and consume some real big power. it would take 16 of them in the shop.

i have also looked at cfl acrylic high bay fixtures with 150-200 w high power CFL's (roughly equivalent to a 400w MH). i can buy the acrylic unit and the high power cfl for about $100 each. it would also take 16 of them.

home depot has the lithonia 2' led high bay fixture for 200 bucks. comparing lumens on all these things is goofy and hard to gauge.

does anyone have any experience on comparing the cfl high bays to the metal halide and then has anyone put those home depot high bay lights in?

thanks

tom

encantofred said:

howdy,

i am building a shop that is 65x70 that will have 18' height for lighting.

i thought at first i would use metal halide high bays, but they are not instant on and consume some real big power. it would take 16 of them in the shop.

Click to expand...

Based on which lamps/bulbs, specifically?

i have also looked at cfl acrylic high bay fixtures with 150-200 w high power CFL's (roughly equivalent to a 400w MH). i can buy the acrylic unit and the high power cfl for about $100 each. it would also take 16 of them.

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Again, WHICH particular fixtures & CFLs? A quick search at 1000bulbs.com turns up these:

http://www.1000bulbs.com/product/8375/FC200-35871.html

But we have no idea what sort of fixture you would be putting them in; and that DOES make a differnce.

home depot has the lithonia 2' led high bay fixture for 200 bucks.

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I presume you mean this one:

http://www.homedepot.com/p/Lithonia-Lighting-2-ft-White-LED-High-Bay-Light-IBH-11L-MV/203812710


???

comparing lumens on all these things is goofy and hard to gauge.

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How so?

Per any number of sources (but http://www.lightingtaxdeduction.org/technologies/high-bay.html is particularly handy), a 400W MH bulb will produce about 36,000 initial lumens. But as you are presumably aware, MH lamps lose quite a bit of output brightness over their normal lifespan; so, per the above-cited chart, the "mean lumens" figure is about 23,500 @ 40% of lamp life.

Fluorescent lamps lose only a relatively small amount of output brightness over their lifetimes (typically about 5-10%, max.); hence, they will still be putting out about 95% of their initial lumens @ 40% of lamp life. So using that MaxLite 35871 cited above as an example, given its 12,000 initial lumen rating, you could expect about 11,400 mean lumens. On a lumens/watt basis, this is roughly equivalent to the 400W MH lamps (tho' the MH types will do significantly better when brand new). But I am at a loss to understand why you think you'd still only need 16 of these CFLs to be equivalent to 16 400W MHs. Their per-bulb output is still only about half of the 400W MH; so by my abacus, you'd need approximately twice as many CFLs as MHs (which is not to imply that this is a bad thing, mind you).

Meanwhile, that Lithonia IBH 11L fixture is rated for "11,000+" lumens (the HD site says 11,200) with an "input wattage" of 149.8; but they don't really discuss the distinction between "initial lumens" and "mean lumens" (yes, LEDs are subject to that same sort of degradation over their useful life; but I'm not sure about the degree, or how that compares to other types of lighting). Still, on a raw lumens/watt basis, this is clearly the most efficient of the lot. HOWEVER, we don't have any credible photometric data for either the MH or CFL fixtures you are apparently considering; so that could change things somewhat.

does anyone have any experience on comparing the cfl high bays to the metal halide and then has anyone put those home depot high bay lights in?

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The above should be enough to get you into the ballpark.

HOWEVER... I am quite curious as to why any mention of LINEAR fluorescent lamps is conspicuously absent? In terms of simple cost-effectiveness, LFLs are sure to be your best bet, probably by a fairly wide margin. Compare the cost of one of those 200W CFLs with the cost of a standard-issue F54T5HO tube (such as http://www.1000bulbs.com/product/90192/USH-3000397.html, for example.) Further, LFLs are also more efficient than either CFLs or MHs; that same standard-issue F54T5HO tube will put out more than 4,500 lumens, using only 54 (nominal) watts to do it.

And finally, there is a MUCH larger assortment of potentially suitable fixtures available, which means it will probably be easier to find something that permits the light to be distributed in an truly effective manner. In particular, your earlier mention of using only 16 fixtures (and "point-source" fixtures, at that!) to cover more than 4,500 ft.^2 of floor area causes big loud alarm bells to go off in my head: Even assuming relatively high mounting, that's likely to lead to rather "spotty" and uneven lighting.

Were it me, and pending the exact mounting height available, I would probably use something like these:

http://www.homedepot.com/p/Lithonia...put-Fluorescent-High-Bay-IBC-454-MV/202838871


http://www.1000bulbs.com/product/93811/BSS-HB4T5.html


http://www.1000bulbs.com/product/64991/PLT-TL5084T5.html


...and use enough of them to keep the fixture-fixture spacing down to the point where the resulting illumination is truly EVEN.

wow, thanks for the in depth thoughts. i am just getting going on selection of lights and didnt mean to illiminate anything. i just thought the cfl's would be easier and i like the look of them. not very scientific.

as for 16 of them, i did talk to a tech support guy at maxlite and he suggested 16 150w high power cfl with an acrylic dome. my comments about comparing lumens was in regard to that as i knew it was less lumens with only 16.

i also was trying to minimize the work on changing bulbs.

thanks again, you gave me more to think about

tom

Lithonia I-Beam 8 bulb T5HO. Polished reflector is narrow light beam, white reflector is wide distribution.

Using Visual............
White reflector
8 bulb will take three rows of 6 lights in line, probably not optimum.

6 bulb will take three rows of 7 lights in line. Still not the best looking setup.

4 bulb will take five rows of 7 lights in line. Good spread of light, lots of fixtures.

I was using 100 footcandle at 2.5 ft above the floor.

Polished reflector w/uplight, 8 bulb, will take 4 rows of seven fixtures (due to the narrow distribution of the light. I select uplight as it eliminates "cave effect" and evens out the light more)

Charles

I was in a shop 3 days ago that was 80x150 and partitioned to 80x100 anyways the inside had the white steel liner in it and the ceiling was close to 18-20'. The building was equipped in the 80x100 area with 16 LED fixtures. Each fixture was about 5' long and had 4 LED instant on lights in each one. I'll post a link to something close to what they had. The building was super bright inside and the guys loved what they had. The fixtures were mounted solid to the roof trusses so they were roughly 18' in the air.

http://www.prolighting.com/hb-100wled-univ.html Not exactly them but you get the idea.

Does the Visual 3D assume 100% output for LED?

MHs are about 75% design lumens and retain 50-60% at end-of-life.

The design lumen for 400W MH is 24,000 to 30,000 lumens depending on the lamp. T5/T8 retrofits often get away with 18,000 to 20,000 lamp lumens as they have >90% lumen maintenance and the retrofit fixtures generally have better light utilization than the old MH bell jar.

MH and T5/T8 fixtures are offered in 3-4 different beam width while LED retrofits are often only sold in one model. You can easily equivalent 400W MH wide with a 175W very narrow in FC level for the level that falls in the beam hot spot, but if this light beam pattern is preferred, they would have installed the narrow distribution fixtures to start with.

This is often the trick used by LED equivalency claims. It only turns out fantastic if the new beam pattern fits the need. It will "spot light" otherwise. LEDs are not a proven technology and we don't really have a solid proof of their lumen loss in real life conditions, especially in high-ambient high-bay. If the drop-in is rated at life to L70 and provides the same beam pattern, the initial lumen on LED needs to match the design lumen on 400W MH. The reasoning is that they start their life at design lumen for MHs, then the output at end of life would be comparable to end of life 400W MH.

^ ^ ^ Says "FALSE FLAG" appointee from fluorescent industry turned loose on GJ in January 2015 !!!

Heaven forbid some LED light fixtures get installed !! . . .

Electric_Light said:

LEDs are not a proven technology and we don't really have a solid proof of their lumen loss in real life conditions, especially in high-ambient high-bay.

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That right there is called "fear, uncertainty, and doubt" (FUD). It's an old trick employed widely by trolls who are intent on dampening enthusiasm for a competing product.

order the BigAss lights. same company that makes BigAss fans

i am just getting ready to install them. i got 21 6 bulb fixtures for T5HO 4' florescents. using 5k bulbs. the fixtures have mirror finish reflectors. my shop has a 20 foot ceiling and the lights are designed to give 100 foot candles at 30 inches.

they are controlled by 6 switches so they are in banks.

will let you know how they work out in a few weeks.

btw, i went with a drywall ceiling and sidewalls with a sante fe 50/50 texture and a semigloss white paint. it looks very bright and airy.

led's were going to be more money than i could spend.

i bought the fixtures and bulbs from http://www.shineretrofits.com/

thanks for all the suggestions and discussion.

tom

I just put in my shop, 6 Lithonia (LBL4LP840) LED Wrap Linear 4' flush mount lights. I have 10' ceiling, and a 24' X 24' shop. I really like the light. One other thing to consider is Color temperature. Mine are 4000K. And I would say that this would be minimum in a shop. The scale goes from 2700K to 6500K. The higher ceiling, I would recommend 4500K. My 4 OLD 8' T2's used 3.8 amps/fixture. These 6, 4' fixtures use .67 amps/fixture. And they are quiet (no ballast noise). These are a bit pricey $145.00/fixture MSRP. With 5 yr guarantee.

mine will really **** power. with a ceiling height of 20' 6" you have to have alot of lumens.

the 6 bulb T5HO fixtures put out 27,000 lumens each and i have 21 of them (567k lumens). i have 5000k bulbs. i like the white light they put out. i have put the same 5k bulbs in my wifes sewing room and it lights up like an operating room over her cutting table.

the led fixture you refer to puts out 4000 lumens. they are nice light, but i couldnt afford to put the amount of led fixtures in that would light my 4600 sq foot shop sufficiently.

i have about 125 dollars in each fixture counting the 6 bulbs. and the fixture has a nice mirror finish reflector.

the downside to mine is each fixture takes 54w x 6 =324w x 21 = 6804 watts or just under 60 amps.

i will likely not have them all on at the same time. i do have 200 amp dedicated service to my garage. (it is a personal garage, not a business).

but i do like to have enough lite. during the day it is fairly well lit with outside light. i have 6 foot long 18" high windows (8 of them) around the 3 sides at 15' high and the two 15' high x 14w garage doors each have 3 insulated glass windows in them.

i wish the leds were cheaper. i would have loved to have them.

all that said, it will be a few weeks before i can turn them on to see how they look.

thanks for everyones comments.

tom

I finally got final on my garage so i have the power turned on.

it is like daylight inside at night. the windows at 15' around the outside walls light up like a ufo from the outside.

i measured using an app on my phone and it says it is 1450 lumens at waist high. or about 145 foot candles. that is with all 7 switch banks on. there are no shadows whatsoever and the bulbs are 5000k so very nice white light. i could operate in there if i wasnt squeemish about blood. ha

since i have them on 7 switches, i can control the light i want without spinning the electric meter more than i need to

tom

here are some pictures of my lights installed. the ceiling is 20 foot high

the wall and ceiling color is actually a bright white which doesnt show that way in the pictures.

tom

encantfred: Are those garage door open buttons (assumed) oem or retrofitted? If retrofitted, how did you wire up the stop button?

hi, they were OEM. they came with the opener. so just followed the wiring instructions with it.

they are wired so you do not have to hold the button down to close or open. just push it once. then the stop button if you want to stop it part way. i like them, looks better than the little plastic buttons.

tom

Did a little research and it's a commercial Liftmaster opener MJ 5011U. I wonder if those button-type can be retrofitted onto 3800 or 8500.

my openers are MJ5011E

but the medium duty openers all use the same controls.

tom

Wow.
LED´s not proven technology! That´s a bold and totally unsupported statement.
Would the poster mind to share the sources of his immense wisdom?
Thanks. I may be wrong and like to learn.
My take.
I general. LED is a physically very well understood action that emits light from a semiconductor junction. A lot of research has been done to get reasonably "white" high efficiency sources. Some guys succeeded and got the Nobel Prize. The use a blue LED with an added integráted filter to get the right color temp, which reduces the efficiency.
They function very well and fault mechanisms are well understood.
In real life the part that will have the lowest MTBF is not the light source but the (probably integrated) driver circuit.

And the race continues. In 5 years MY guess is that a LED that emits a pleasant white spectrum without added filters.

I have worked in an office landscape which had 100 % general lighting by LED integrated in the ceiling panels. Wprked perfectly, very pleasant.

And theuse a lot less power for the same light , and lasts a lot longer than any incandescent or Fluorescent light source.

Ola

Trey T said:

Did a little research and it's a commercial Liftmaster opener MJ 5011U. I wonder if those button-type can be retrofitted onto 3800 or 8500.

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I have 3 3800's....that would be nice. I'm also thinking of the smart phone remote control that I just found as an option two days ago.

i am a geek so i did check to see if the myq can be put on the mj5011 that i have but they cannot do it. i would love to have that option. i also have two liftmaster swing gate openers that i would like it on but only this years version offers that. oh well, i will have to live with remotes. but it would have been nice to operate the swing gates via my phone

tom