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  1. #31
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    Default Re: Future of non-IC lights

    Here is one of the best comparisons of LED vs Incandescent vs CFLs I've seen:

    http://www.designrecycleinc.com/led%20comp%20chart.html

    In summary:
    LEDs have six times the live span of CFLs (and don't burn out when used base up)
    LEDs use roughly half the energy of CFLs
    LEDs contain no TOXIC mercury and are RoHS compliant
    LEDs result in less than half of the Co2 emissions (and sulfer oxide and nuclear waste)
    LEDs are not sensitive to lower temperatures (outdoor use)
    LEDs are not sensitive to humidity like CFLs
    Cycling LEDs on and off has no impact, can drastically reduce CFL lifespan
    LEDs turn on instantly to full brightness
    LEDs are very durable, CFLs not so much
    LED heat emission is 3.4 BTU/hour, CFLs are 30 BTU/hour
    CFLs have an annoying tenancy to catch on fire, smoke or omit an oder when they fail, LEDs do not
    For 1,110 lumens, LEDs use 9-13 watts, CFLs use 18-25 watts
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  2. #32
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    Default Re: Future of non-IC lights

    Quote Originally Posted by bobkni View Post
    The reason for the heat is not the bulbs but the step down transformer inside the bulb. Led's are all 2 or 3 v I believe ( if I remember correctly, from the explanation given to me by a electrical engineer yesterday ). If you notice how heavy the 120v led bulbs are compared to the low voltage bulbs, it's because of the weight of the transformer.
    The latest LED bulbs do not use transformers, they convert the 120v AC to 120v DC and chain a bunch of LEDs together. This avoids the use of a transformer. They are getting efficiencies of 120 to 150 lumens per watt!
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  3. #33
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    Default Re: Future of non-IC lights

    LEDs have six times the live span of CFLs (and don't burn out when used base up)
    LED life is shortened with heat. Trying to get more lumans per LED makes them run hotter in general. Sams club sells some bulbs that have 10,00hr rated life right now. Incidentally, they get to say how they rate the life, and that might mean half of them fail by 10,000 hours.
    And the more LEDs are overdriven, the more the light output degrades over the life.

    LEDs use roughly half the energy of CFLs
    There are still a lot of them on the shelves that do not have the luminous efficacy of CFLs.
    Here is the great wikipedia’s take on it:
    http://en.wikipedia.org/wiki/Luminou...acy#Examples_2

    LED heat emission is 3.4 BTU/hour, CFLs are 30 BTU/hour
    I think that would be all over the map still.

    For 1,110 lumens, LEDs use 9-13 watts, CFLs use 18-25 watts
    Got a link to those 1,110 lumen 9 watt LED lamps so I can buy some?

    The latest LED bulbs do not use transformers, they convert the 120v AC to 120v DC and chain a bunch of LEDs together. This avoids the use of a transformer.
    I was wondering if they would do it that way. BTW…LED’s would convert the AC to DC all by themselves.

    They are getting efficiencies of 120 to 150 lumens per watt!
    Got a link where I can buy some of those? I thought the best option for white light was the super t8’s as far as lifetime costs, replacement of lamp costs, and efficiencies. or if you are outdoors in the cold the PSMH's.

  4. #34
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    Default Re: Future of non-IC lights

    Quote Originally Posted by charles View Post
    Agreed, but somebody asked me to give an example.

    I'll let you do the research on that. I didn't make a broad statement, I said some LED bulbs are crap.
    I believe the word first used was "lots" not some, but no matter, cheap and less than optimal bulbs can be had in most all forms, thus the car:horse bit.

    A couple weeks back I was at a facility where they had installed occupancy sensing CFLs in the break, bath, some hall passages and storage areas. They had not paid much attention and used lesser bulbs [they claimed were handed out by the energy saving folks from the elec utility] that were rather slow starters.

    Full [lumen] output took about 3-5 minutes, or about the time they were on per cycle. Once going they were quite high output [lumen:watt], but in this instance/use they were probably cut back to 60-70% of potential at best. Owner wanted to replace what was there with higher watt bulbs to overcome. Solution was simply selecting a different bulb with a better starting L and, as a kicker going from the 2700ºk to 4100ºk - more and 'brighter' light, same watts.
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  5. #35
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    Default Re: Future of non-IC lights

    Quote Originally Posted by johnny watt View Post
    LED life is shortened with heat. ... And the more LEDs are overdriven, the more the light output degrades over the life.
    The LED element is very small so the heat from the LED is concentrated in a very small area and can degrade the LED. That is why good bulbs have decent heat sinks to conduct the heat away. It isn't that there is a lot of heat, it is just that you don't want it to build up in the LED. Good cooling is part of what results in the 50,000 hour life. Take a look at the CREE LR6, it has a massive heat sink. That is also why it can be burned in any position or in a recessed housing, unlike most CFLs that will be toast.

    Quote Originally Posted by johnny watt View Post
    There are still a lot of them on the shelves that do not have the luminous efficacy of CFLs.
    Could be, although it is pretty hard to make an inefficient LED. You have to work at it... Lousy electronics in the power supply or using the fallout LEDs from production.
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  6. #36
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    Default Re: Future of non-IC lights

    Quote Originally Posted by johnny watt View Post
    Got a link to those 1,110 lumen 9 watt LED lamps so I can buy some?
    Sure. Lextar has demonstrated a new high efficiency bulb that gives 1000 lumens, consuming only 8.3 watt and peaking the efficiency at 120 lm/W in the warm white color temperature of 2700K.

    Cree has 254 lumen-per-watt white R&D power LED in the lab. Cree generally produces the most advanced LEDs. This should give you an idea where things are heading. It will only get better while mercury laden CFLs are left in the dust. (Fortunately for us...).
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  7. #37
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    Default Re: Future of non-IC lights

    I ran across this and found it interesting:
    ----------------------------

    Why Eartheasy no longer sells CFL bulbs:

    We have discontinued sales of CFL bulbs because we are concerned about the inconsistent quality standards among overseas manufacturers of CFL bulbs, and the use of mercury in these bulbs.

    The rapid development of LED bulb technology is bringing newer LED bulbs to the marketplace which are safer, longer lasting and more energy efficient than today's CFL bulbs. The price of LED bulbs has recently gone down to a more affordable level, and now delivers the best cost-savings over the life of the bulb when compared to CFLs or any other light bulb available today.

    If you can't see spending what it costs for an LED replacement now, at least switch to a CFL to reduce your costs for one bulb life of about 5 years and then re-evaluate the situation then. It will reduce the amount of mercury that is released into the environment and reduce power demands.


    From: http://eartheasy.com/live_energyeff_lighting.htm
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  8. #38
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    Default Re: Future of non-IC lights

    Quote Originally Posted by BeachBoy View Post
    Sure. Lextar has demonstrated a new high efficiency bulb that gives 1000 lumens, consuming only 8.3 watt and peaking the efficiency at 120 lm/W in the warm white color temperature of 2700K.

    Cree has 254 lumen-per-watt white R&D power LED in the lab. Cree generally produces the most advanced LEDs. This should give you an idea where things are heading. It will only get better while mercury laden CFLs are left in the dust. (Fortunately for us...).
    But where can I buy them?

    I’ve been using LSI and BETA LEDs for a while. Originally they were close to $1k/each for a 400w mh equivalent. I used them to score points with the pointy-headed librul fascists on planning boards. They bring up dark sky initiative and I say, “even better, were using LED’s because your town deserves them”. They don’t bother to check that LEDs are worse for dark sky initiative because of the color of the light. Then they don’t make me use ridiculously low exterior lighting levels.


    The LSI has a slightly better looking CRI. The rep tells me the LEDs have phosphorous in them to convert uv to visible light and LSI ops for the better compounds. But reps are bullshippers so who knows.

    Lately I can get 400w equivalent for under $500 so I have used them when I didn’t need to, just for electricity and heat output and maintenance savings. I never get any rebates unless I am retrofitting and the energy retrofit cartels have the rebates all but locked up with Nation Greed, so I have to sub it out to them.

    I’m still waiting to find something acceptable for interior retail lighting. I just saw a McDonalds redone that used a can every 16 square feet with an LED lamp and then added pedant lighting on top of that. Cheap fixtures and lamps, but a lot of holes to cut and install. Plus adding pendants on top of that seems like they are not worth it yet.

    As far as the OP goes, I assume he would purchase lamps from orange depot and he would be hard pressed to find an LED anywhere else that would not work. He can sue me in NY at Johnny Watt LLC if I am wrong. But since it is just a hypothetical question I don’t know what damages he could ask for.

  9. #39
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    Default Re: Future of non-IC lights

    Quote Originally Posted by MarkMc View Post
    I believe the word first used was "lots" not some...
    What, you don't think Wal Mart has lots of LED's?

    OK, try Big Blue at http://www.lowes.com/pd_171150-28839...e|0&facetInfo=

    or Big Orange at http://www.homedepot.com/h_d1/N-25ec...&storeId=10051

  10. #40
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    Default Re: Future of non-IC lights

    Why don't the light covers, ie. Tenmat, cause the housings to overheat?

  11. #41
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    Default Re: Future of non-IC lights

    Those aren't designed for incandescent bulbs, so the heat generated will less.
    There are some larger ones available made from some sort of fiber board and another version made from metal.

    The general concept is to spread the heat onto more surface area so it can dissipate.
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  12. #42
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    Default Re: Future of non-IC lights

    Beach, that chart is not all that accurate.
    Nearly every statement is not exactly right.
    CREE LR6s are 650 lumens, 10.5 watts. Good fluorescents smoke that ratio.
    We use CREE fixtures, they have very nice light and have been reliable. They only dim down so far before they start blinking on and off, and the light turns very pink when you get much below 50% or so, plus they cost $75...but they're about the best out there.
    Fixture efficacies for LEDs are still not great because LEDs don't naturally put out the right color light and don't naturally work on 120v AC. They're getting there and I'm looking forward to them being more competitive. But they certainly don't put out twice the light for the electricity, in fact it's more like 90% of the light as a CFL depending.
    Meanwhile CFLs are ubiquitous and inexpensive and seem to be perfectly adequate for most purposes.
    One other thing to think about...the current 'lifespan' of LEDs is based on when they put out 70% of original amount of light (they dim as they age). I am guessing our clients may notice the dimming well before the nominal lifespan. In that case some of the advantage of the long life is lost.

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