Lighting Smack-Down: 4′ Fluorescent Tubes vs LED

by Ben N on December 12, 2014

Recently, a friend of mine decided to do some garage lighting upgrades, and it inspired me to do the same. While I recently upgraded a number of CFL bulbs to LED bulbs, my shop-light fixtures were still using a combination of T-12 and T-8 four foot fluorescent tubes.

At the hardware store, I saw that they now carry an LED direct replacement tube. This is an LED-based tube that goes directly into a 4-foot fluorescent fixture WITHOUT any rewiring or modification. (Up to this point, LED lights put into fluorescent fixtures typically required cutting wires, removing the ballast, or other electrical modifications.) I bought a pair of these tubes and thought I would compare them against the best fluorescent tubes I was already using.

So, I present to you the Fluorescent vs LED Lighting Smackdown!

In this corner, at four feet long, one inch diameter, 6500 Kelvin, made of glass, using 32 watts, is our current champion, the T8 Sylvania Octron Eco! (Hhhhhaaaaaaaaaa *crowd noise*)

And in this corner… The challenger… also at four feet long, one inch in diameter, 41oo Kelvin, plastic housing, using 19 watts, the Osram/Sylvania LED SubstiTUBE I.S. (HHHAaaaaaaaaaaaaa *more crowd noise*)

Lets compare these two tubes in a head-to-head showdown of Cold-weather Performance, Brightness, Energy Use, Heat Output, and Cost! (*ding!Ding*)

To start with, I headed out to my unheated, detached garage. I don’t have any fluorescent tube lights in my house, only my garage, so it made sense to start there. I plugged in the new LED tubes into a fixure, and held it up near an existing garage fluorescent fixture with the traditional T8 bulbs in there, then turned them all on. The LED tubes came on INSTANTLY at full brightness. The Fluorescent tubes were terribly dim, almost hardly on at all. Temperature was right at about freezing, 32F/0C.  In my part of the country, it’s typically below freezing all winter. Cold weather start? The win clearly goes to the LED tube.

I then waited thirty minutes for both sets of tubes to come to full operating temperature. I took another photo to compare the two. The LED tubes were still brighter than the fluorescent. Again, the cold-temperature operating win goes to the challenger.

(Note: All photographs were taken using a Nikon D90 DSLR with manual white balance set to the FLASH setting. At that setting, the 6500K fluorescent tubes will always appear “bluer-than-white” and the 4100K LED tubes will appear “redder-than-white”. Photographs were taken at whatever shutter speed and iris for an acceptable exposure, but always with both sets of bulbs in the same shot for a fair comparison. Also, cameras still do not have quite the range of exposure as the human eye. The difference in brightness between the two sets of bulbs was LESS noticeable in the photographs and MORE noticeable to the naked eye. Photos were edited only using scaling or cropping, no color correction or brightness/contrast changes.)

Next, I came inside and had both sets of tubes in matching, electronic ballasted fixtures on the floor. I allowed the fixtures and tubes to come to room temperature, then turned them on and allowed them to run for about an hour before returning to conduct the rest of the tests.

Although the fluorescent tubes were now brighter than they were out in the cold, they were still not quite as bright as the LEDs, although closer. Even at room temperature, the LED tubes still win the brightness test!

Next, I pulled out my Kill-a-Watt energy meter and tested each set of bulbs. Both measured zero with the fixture off. (Always nice to check on phantom loads!) Testing the Fluorescents, they clocked in at 58 watts energy use for the pair. (This energy meter only measures to the watt, no fraction or decimal.) That’s 29 watts each – LESS THAN the rated 32 watts listed on the bulb. I then tested the LED tubes – 39 watts for both, or 19.5 watts each – just a hair MORE than the 19 watts on the label. So although the LED bulbs use only two-thirds (67.24%) the energy of the fluorescent, I was surprised that the fluorescent tubes did use less energy than I thought. I’ll call this one a tie – the LEDs did come in as the winner on energy use, but the fluorescents were more energy efficient than I expected them to be!

Next up, heat. While an incandescent bulb can easily burn your hand, we usually think of fluorescent lights as cool, but how will they stack up against LED? I got out my instant-read infrared thermometer and tested both sets of bulbs, testing several points at both the ends of the bulbs and the middle. The fluorescent ranged from 94 degrees F in the middle up to as high as 126 degrees F on the end. I also felt with my hand and noticed that the fluorescent tube was pretty much even temperature all the way around its diameter.

On the other hand (literally…) the LED bulb felt warmer on the back of the tube than the front. This makes sense, the back of the tube has the electronics (and emits no light) and the front is really just a diffuse plastic cover. So, I tested the temperature of both sides of the LED tube, including mounting one of the two tubes “backwards”, facing into the fixture, so I could get a clear temperature measurement of the back. The front of the LED ranged from 79 to 88 degrees. The back of the LED ranged from 91-95 degrees. Essentially, the hottest part of the LED tube was the same temperature as the coolest part of the fluorescent, and there was as high of a temperature differential as 48 degrees. This is nothing compared to incandescent bulbs, but if you are using lighting in a hot climate where you are also using air-conditioning, every degree makes a difference. Also, lower temperatures generally mean longer life for electric and electronic equipment. The winner? The LED tubes… again.

Next up, the shock test.
No I did not intentionally break any bulbs. I’ve done that enough in the past to to tell you that glass fluorescent tubes break pretty easily. They make a HUGE mess, and some people have concerns about the very small amount of mercury in them. I did tap on the LED SubstiTUBE with my fingers and a pocket knife. It’s all plastic. The tube itself has some flexibility to it. It felt pretty shatter resistant – a good quality for a light in a workshop where moving a ladder or flipping a board end for end may accidentally hit a fixture. I also recently dropped an LED bulb on my driveway. It bounced. No damage at all was noticed on it, and it still worked fine. Shock test winner? LED, every time.

But what about longevity? Right on the box, the Sylvania LED SubstiTUBE is rated for a 45 year life-span. T8 are typically rated for 20,000 hours. I couldn’t find the fine print on the materials that came with the LED bulb for how many hours per day their 45-year lifespan was rated at, however, the 5-year warranty was based on running the tubes 24 hours per day for those five years. If that also applies to the 45-year lifespan, that’s an insane 394,200 hours. Whichever way you slice it, the LED tubes will have a longer lifespan than the fluorescent. Of course I haven’t been running these tubes for that long, I just got them yesterday. However, a good little trick I learned a while back is to simply use a marker to write the date of installation on any new bulb you install. If it ever burns out, you know exactly how long it lasted.
Lifespan win goes to the LEDs – not necessarily from personal testing, but from LEDs in general having a very good track record.

Lastly, lets look at price. I got the LED tubes for $24.99 each. Yep, still rather expensive for light bulbs. (Although less expensive than they have been, and prices continue to drop.) On the other hand, T8 bulbs go for $10 for a two-pack ($5 each) or $25 for a case of ten ($2.50 each.) On cost, the traditional fluorescent tube is the winner, hands-down.

So what does this all come down to? The Sylvania LED Substitube won in EVERY SINGLE CATEGORY except cost! It’s clearly the better bulb, but is it worth it? I leave the answer to that one up to you, dear reader, but here’s how I feel about it…

In my case, I need some good area lights in an unheated garage. In the winter, when it’s cold, we also often have the cloudiest days, and an 8am sunrise with 4 pm sunset. When I need the light the most is when fluorescent tubes are at their ABSOLUTE WORST! So, the LED tubes are great with their instant on full brightness AND being brighter than the fluourescents even at full temperature. However, I’m not made of money, so I’m not likely to run out and buy any more of these tubes than I already have. However, a single set of the LED tubes is bright enough to light up a really good portion of my garage instantly, while other fixtures with traditional fluorescents can take a while to warm up, but then light up the sides and corners of the garage. I’ve also found that medium base, screw-in, LED bulbs are really now reaching reasonable prices. I’ve bought a fair number of them for $6 each. Four of those spread out will light up an area as big as the LED tube.  I’ve also noticed that the tubes are bright enough that there’s no reason to use two of them in a fixture. A single tube in a double fixture is more than enough light for most work areas.

In other, more subjective qualities, I REALLY like the COLOR of the 4100 Kelvin LED tube. I usually don’t care for fluorescent 4100K bulbs. They typically have sort of a “yucky” white, which I think may be related to the notorious “green-spike” that is common to fluorescents. The quality of the light from the LED tube is far better than its fluorescent cousin. It actually comes across as a very pleasant sunny, warm tone of light.

LEDs sure have come a long way. Still a little pricier than than incandescents and fluorenscents, they have some qualities that are great for my application, especially cold-weather performance and shatter resistance. So, I’m off to install my new shop light now, and if it burns out in the next 45 years, I’ll let you know.

Til next time, stay charged up, well-lit, and warm!


{ 1 trackback }

LED's replacing 48" Fluorescent tubes - Page 2 - EcoRenovator
December 12, 2014 at 3:35 pm

{ 2 comments… read them below or add one }

1 Tim Fulton December 15, 2014 at 8:13 am

Thanks for the comparison Ben!

2 stacey July 30, 2015 at 1:48 am

This is Stacey from Shenzhen Longtop Technology Co., Ltd.

We have been in led lights this line for long time, exporting to different countries and districts all over the world successfully, ensure good quality, reasonable price and prompt delivery time. Now our led lights have a competitive price with CE&RoHS certificates.

Leave a Comment

You can use these HTML tags and attributes: <a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <strike> <strong>

Previous post:

Next post: