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  • #16
    Here is a link to an Energy Star presentation that compares different types of lighting.


    • #17
      Originally posted by BackBlast View Post
      By this link you have overstated the case for both CFL and linear fluorescent. I was able to find a 109 l/w tube for sale (which claimed to be the best), and I noticed the wonderful "up to 109" in it's marketing literature.
      No not really I said it was an old link, I just used it as it is a good summary and easy for lay folks to see graphically. As for the flourescent bar graph it includes all tubes not just T5HO. And yes I know incandescent goes up to 30 l/w with tungsten high temperature lamps and was my reference for comparison to LED's.

      My whole point is folks have to be very careful when selecting a light source specifically those folks using off-grid battery systems. A good example is with CFL's, they are not created equal and run quite a wide range of efficiency. Just recently on this forum a person was shocked when his battery run times were 1/3 of what he expected. What he learned was his 13 watt CFL lamps when ran through the inverter was drawing 55 watts per lamp when he budgeted only 15 watts per lamp. He got snake bit for a couple of reasons.

      1. He was using inexpensive CFL's manufactured in China with really poor ballast running a PF of .57.
      2. Not considering inverter conversion efficiency. He is running a large inverter on small loads.
      3. Using a MSW inverter rather then TSW..

      Anyway I think we have both made the same point and agree, LED's are not what they are cracked up to be.
      MSEE, PE


      • #18
        I have tried several of the LED bulbs currently available in the UK.

        Of the 1-3 watt bulbs I have tried the spot type, the ones used in recess lighting are quite good especially as a replacement for halogen.

        The LED bulbs as a replacement for CFL are in my opinion dismal and currently far too expensive at around


        • #19
          For a chart that compares types of lamps please see

          An article about low pressure sodium lamps but the chart is for all types.


          • #20

            why can't you go for recessed lights.

            Last edited by russ; 04-11-2011, 08:36 AM. Reason: removed links
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            • #21
              I have no Problem with leds

              if you use tri chip leds they don't produce much heat but put out allot of light.
              Never under estimate the power of hard work. In time something magnificent happens. Dreams are only dreams if you don't push forward. Have a productive day. Tomek.


              • #22
                My friend whose a San Francisco electrician was telling me that the T5 fluorescents are significantly better than the leds, but I haven't heard of tri chip leds. I'll have to ask him about these types of leds. How are they compared to the T5 fluorescents?


                • #23
                  Originally posted by jerld View Post
                  . How are they compared to the T5 fluorescents?
                  They do not compare. T5HO efficiency is around 105 lumens/watt. Best LEDs you can buy today are around 60 to 70 Lumens/watt..

                  But here is the catch and it is a big one. The LED light is measured inside the beam the light produces which may be as wide as 120 degrees. Outside of that beam the light level falls to almost nothing as LED light is very coherent like a laser. That makes them good for flash lights and task specific applications.

                  T5 light level is measured fully around in a 360 degree sphere. Use reflectors and lenses to match the beam angle and that 105 L/watt jumps up to 420 L/watt. So they are not even close.

                  Now with that said go into any new warehouse, Walmart, office, sporting arenas and look up at the lighting. It is not LED. It is T5HO High Bay lighting. The reason is very simple, they are the most efficient. The US government will not allow LED lighting in any building because they do not meet minimum efficiency standards of 90 Lumens/Watt. Only T5 and T8 can do that for interior lighting.
                  MSEE, PE


                  • #24
                    As a caver, I've been seeing and using various LED headlamps for a while, and have been interested in seeing this technology turn a little more efficient and come into the home. The blue ones are terrible, IMHO, and I think its hard to see true distances correctly with blue light. The newer white lights are way better than the old ones and brighter to boot. Some of the headlamps they are coming out with now a days can make up to 1600 lumens with only 4 bulbs. Amazing! Anyone heard of these Cree super efficient LEDs as mentioned in this article: Will probably have to wait for the price to come down on these.

                    I have a few 1 watt LED headlamps and the first time I loaded batteries into them to see how long they would last, they stayed illuminated for a week! Granted only the first 10-12 hours are bright, but its really incredible that they can stay illuminated with such low power for such a long time. I have a few headlamps that have both incandescent and LED bulbs in them. I like the light from incandescents best, but after they wear the battery down and go out I can still turn on the LEDs using the same mostly dead batteries. And they are the only bulb that you can dunk in water time and again and always come back on. I would love to make the switch to LEDs for home lighting, especially for outdoor lighting since they are so darn hardy.