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I previously worked on Virtual Reality and other hardware at Valve.  I currently work at Google[x].

Prior to starting at Valve, I built computer peripherals such as keyboards, mice, and joysticks that were designed to be used inside MRI machines.  My company, Mag Design and Engineering, sold these devices directly to researchers at academic institutions who used them to publish scientific papers in peer-reviewed journals.

After work, I spend time on many different types of projects that usually involve circuit design, machining, material selection, and general fabrication/hacking.  My favorite place to be is my home workshop.

ben dot krasnow at gmail




Friday, May 27, 2011

Shop lighting upgrade: T5 vs T8 fluorescent vs LED

I am in the process of upgrading the lighting in my shop. It currently has a number of 4-lamp and 2-lamp T12 4-foot fluorescent fixtures. The best solution is to replace the ballast in each of these fixtures with high-efficiency electronic ballast ($15), and replace the lamps with T8 high-CRI bulbs. This will save energy, and greatly improve the quality of the light. LEDs and T5 fluorescent are MUCH more expensive to install, and their energy savings are not nearly enough to justify the cost. Most LED systems actually use more energy than T5 or T8. Remember that running a T8 with an electronic ballast will provide more light than it's nominal rating, which is for magnetic ballasts. T5 are always rated for electronic ballasts, so it is not a fair comparison.

For new fixtures in my shop, the cheapest/best solution is to buy $10 "shop lights" and replace the ballast. The total fixture cost is $25, and efficiency is 96 lumens/watt for a total output of almost 6000 lumens. It can't be beat! Commercially-available T8 fixtures with electronic ballasts are more expensive, and the quality of the ballast is suspect.


  1. Very interesting vid, thanks.

  2. Thanks for the detailed research and report! I've been thinking about this a lot (for the whole house, not just the shop).

    One question: you talk about the lumens / dollar cost for buying the fixtures and "bulbs", but don't mention the life of the bulb. (Would "emitter" better cover LEDs descriptively?) Does the cost for LEDs come down significantly when you consider the lifetime of the fixture, or is the cost of fluorescent bulbs low enough to not to change that much? I was under the impression that LEDs last for something on the order of decades, but that may be overly optimistic.

    I agree that the quality of (white) light produced by LEDs has a ways to go yet, and that alone may justify waiting. It's good to know that fluorescent is a viable, efficient, high quality choice.


  3. well done and thanks. I've got 6 2x T12's in the garage and was wondering if they really were the right lighting. Now I know that they are not and upgrading them is easy with new ballasts and T8 bulbs. I'm making a run to HomeDepot today and will see about getting the upgrade parts if the prices are right.

  4. Rob, the high quality 4' T8 bulbs only cost $2 to $4 each and are rated 24,000 hours at 3 hours per start. The Bridgelux LEDs claim 50,000 hours above 70% of initial lumen rating. Considering that LEDs are many times more expensive per lumen than fluorescent tubes, "bulb" replacement is actually more costly with LEDs!

  5. Awesome post. Helped me with some questions I had in making a high light, lower energy use hood for some of my larger aquariums.

  6. I've been somewhat disappointed with CFL's in the past - they never seem to last anywhere near as long as they claim (for me about 1 or 2 years max, nowhere near 7 years or so they used to claim). Are these tube type flourescents any better? You say that T8 bulbs are rated 24000 hours but many I've seen seem to fade to dingy yellow well before this (we have 6 pairs T12's in the kitchen and it seems like they only last maybe 1-2 years before dimming or becoming yellow or start flickering). I've only started buying some LEDs but so far they're working smoothly and steadily, no sign of fading/yellowing/flickering - I've only had these for a few months to about 1 year. I've bought a few different no name chinese ones from 3w to 11w. I had a few 13w but they were all defective (got hot and died after only a few hours) - all from one source. The 3w to 11w ones so far are nice and cool and performing well (some spotlights, some bulb replacement types - all E27 sockets). I paid between $4 to $14 (more power, more $) but I figure that if they last many years they may make back the cost in electricity savings (haven't tried to do a detailed comparison). One thing that really annoys me is a flourescent that I put in only a year ago dimming or flickering or going yellow - I'm too cheap to change it until the situation becomes intolerable so I live with it for a few months but it's irritating. And I'm concerned with polluting the earth so much with changing out so many flourescent bulbs. If the LEDs prove reliable over the long run, then I don't mind paying a bit more and if they're close to equal or better then in my book, they're a winner.

  7. Anonymous, CFLs mostly die early because the internal electronic ballasts are built extremely poorly. If the manufacturers spent just an extra nickel or dime on the parts, CFLs would be much more reliable. If you retrofit tube-type fluorescent fixtures yourself, you can choose to buy the ballast from any supplier that you want, and can choose a company with a reputation such as Sylvania or Philips. Inexpensive fixtures with already-installed electronic ballasts are probably using a much less reputable (and less expensive) brand of ballast.

    Flickering fluorescents are probably caused by bad magnetic ballasts. Electronic ballasts will probably just die completely.

  8. I'm looking for an outdoor shop light (waterproof) that can be plugged into a standard 110v outlet. any suggestions?

  9. How do the old T12 lamps perform if you replace the ballast with one that operates at 30kHz?

  10. T12 bulbs on electronic ballasts would probably be almost as good as T8 in terms of efficiency, but finding such ballasts is difficult since T8 is becoming the new standard.

  11. Thanks for doing this video. You just saved me from making an expensive LED mistake on my new shop.

  12. can you please e-mail me the name of the green an black cataloge please. scotth_99@hotmail.com thanks for your time.


  13. The catalog is a lighting solutions catalog from Newark (Element 14).

  14. Hi Ben,
    The reason how I did find your site, was because I was browsing the web, for TL5 or TL8 lights and a 12v inverter.
    In the results, you site came up, and did read it last week with plessure.
    However nothing found specialy for 12v and TL5 or 8 on the web. Do you have any knowledge about that subject or any link that you know of?
    Thank you very much.

    PS. I also did enjoy your posts about impedance and the transistor! More to come?

  15. Sorry, not clearly written, but I am looking for a DIY 12v TL8 inverter design/scheme. To build one by myself.
    Thanks again

  16. Ben thanks for the article. I'm getting ready to have my shop complete 24X30 with 10' walls. It's a metal shop and considering lights. Question I have is would I be better off with 2 bulb or 4 bulb T8 strips. I plan on doing your electronic ballast upgrade to each strip I buy. Any recommendations on which sylvania ballast to buy and from where.


  17. is there a difference between the ballast you recommend and say one that is included in a 18.00 utilitech fixture sold by lowes with an electronic ballast already included?


  18. Nice video. Wouldn't it be nice if the lighting industry was as honest? But, they aren't.

    LED's are kind of nice to consider in cold areas because they don't need to warm up.

    But, LED is very expensive.

  19. Home Depot sells a t8 2 light electronic ballast strip for $27

  20. How things have changed in 2 years.... "and efficiency is 96 lumens/watt for a total output of almost 6000 lumens" was taken from the opening statement. This is still true but you must consider that those 6000 lumens are being scatered everywhere in all 360 degrees of the tube. Some comes down to the working plane, some reflected down, some up, alot if it sideways.. Wasted light, wasted energy, wasted lumens.

    LED as we know "should" be a super long life solution. Does give directional lighting and can be "controlled" to offer an aesthetically pleasing lighting solution. At Fitzgerald Lighting in Cornwall England I have been designing LED platforms, Diffusers and fittings to do what Lighting should do.

    Fires, Candles, Gas lamps, incandescent bulbs, fluorescent tubes all scatter light and waste energy and rely on heat. Our LED profiles a, do not waste energy on heat. b, offer the user more lumens per circuit watt from the fitting than any other in their class on the market to date. c, are photometrically proven to deliver all of the light where you want it, not just need it as it must offer aestheticly pleasing ambience too. d, are super reliable.

    LED fittings that use "heat sinks" are over working and wasting valuable energy generating that heat, dropping potential lumen per watt figures, dropping LED life and degrading the important whitle light generating phosphors killing lumen output over time, sometimes with huge % loss in within the first use...

    Safe to say, LED fittingd designed correctly, manufactured propperly and executed perfectly are the future. Not these cheep hot unreliable imports posing as "energy efficient" "fit and forget" "50,000 hour LED" fittings... They are certainly not going to last

    Buyer beware!

  21. Great Video even 3yrs later, it still makes sense.

    Thanks for sharing

  22. Great blog! Just curious of an update if this still applies for best value for the money per lumen, efficiency, etc? Thank you!!

  23. I haven't done much in-depth checking recently, but T8 is still likely the cheapest in $/lumen installation cost as well as lumen/watt running cost. LEDs will eventually overtake, but I don't think it's happened yet. T5 seems artificially expensive and unnecessary.