replacing CFLs with LEDs

Discussion in 'Environmental Discussion' started by dhanson865, Jul 24, 2013.

  1. dhanson865

    dhanson865 Expert and Devil's advocate

    Joined:
    May 24, 2011
    851
    186
    0
    Location:
    TN, USA
    Vehicle:
    2005 Prius
    For me $0.10 per kWh is about right and am I doing the math right saying that 3 watts time 10,000 hours = 30,000 Wh = 30 kWh? If so 30 x $0.10 is about $3 energy savings.

    I do live in the south so I'll save money on AC most of the year but I figure that is almost too small a benefit to bother with calculating since I'm already using CFLs in all the sockets.

    CFLs are about $1.50 a 13w bulb for a 10,000 hour life (x 2.5 bulbs for a total of $4.25) vs $10 or $15 a bulb for a 25,000 hour life.

    Now the wattage depends on the usage as a down facing can light I can probably go for a 7 watt LED with a more directed beam vs non can light fixtures (floor lamp, ceiling fan, bathroom vanity) where I might use a more omnidirectional bulb and end up using a nicer 9 watt bulb.

    So for the kitchen can lights the wattage saving will be 6 watts x 25,000 hours versus a purchase price difference of $6.75 vs a savings of $15 electricity?

    For general use the wattage saving will be 4 watts x 25,000 hours versus a price difference of $10.75 vs a savings of $10 electricity?

    If I got the electricity math right it looks like it is worth me switching out the 3 can lights in the kitchen now. It also looks like I'll have to wait for the Cree or Philips bulbs to drop in price a bit before I start replacing the rest of the bulbs in the house due to my low cost of electricity.
     
  2. FL_Prius_Driver

    FL_Prius_Driver Senior Member

    Joined:
    Jun 17, 2007
    4,319
    1,526
    0
    Location:
    Tampa Bay
    Vehicle:
    2010 Prius
    Model:
    I
    I've changed out to LEDs are nearly every major socket for a couple of additional reasons:
    1) I like the color balance of the LEDs I use.
    2) Much harder to accidentally break an LED, and the mess of shattered glass is not possible if I did.
    3) LED bulbs don't look goofy in exposed bulb holders, like ceiling fan fixtures, whereas the spiral CFLs were distracting.
    4) No detectable flicker.

    Those add up to a lot more than 75 cents of value to me. The price tag is important, but the quality of light makes more difference than I originally thought. Make dang sure the spreadsheet does not overshadow the reason for having nice room lighting in the first place.
     
    Rae Vynn and DadofHedgehog like this.
  3. john1701a

    john1701a Prius Guru

    Joined:
    Jan 6, 2004
    11,835
    4,561
    57
    Location:
    Minnesota
    Vehicle:
    2017 Prius Prime
    Model:
    Prime Advanced
    I couldn't stand CFLs, so many shortomings and only a temporary bridge to LED. So, I skipped them going straight to LED way back in 2010.

    Years later, I'm delighted with that choice.and am pleased to see how much price has come down.

    Whether or not you can justify the cost is a personal decision. The reduced electricity consumption is something everyone will benefit from.
     
    Rae Vynn and austingreen like this.
  4. dhanson865

    dhanson865 Expert and Devil's advocate

    Joined:
    May 24, 2011
    851
    186
    0
    Location:
    TN, USA
    Vehicle:
    2005 Prius
    Funny, I've been using CFLs since the late 90s, I still have some from 2002 to 2005 in daily use.

    I'd like to switch to LEDs but until recently the dollars just weren't there. I can't afford to do it until it is cheaper to buy and use than CFL.

    The cheaper LEDs have been inefficient, hot, but good quality light. Now they are finally making some in the $8-$16 range that i'd like to have. If my electric rate were higher I would have switched last year.
     
  5. SageBrush

    SageBrush Senior Member

    Joined:
    Jun 4, 2008
    11,627
    2,516
    8
    Location:
    Southwest Colorado
    Vehicle:
    2012 Prius v wagon
    Model:
    Two
    In general I calculate lifetime savings like OP did, but not for LEDs. The problem is two-fold:

    1. If the light is used for only a couple hours or less a day, you simply are not going to reach 25k hours.
    2. The reported long-life is the LED, while failure occurs from the electronics. So instead I multiply my hourly use by 5-10 years multiplied by the watt savings to estimate my kWh savings from a replacement.

    I'll also point out that LED tech is dropping in price and increasing in lumens/watt very quickly. If the current setup is acceptable and substantial savings from an LED replacement is not obvious, waiting a year or two strikes me as a very reasonable choice.

    My house is stuffed with CFLs, and 5 LED bulbs:
    2 LEDs in the kitchen for immediate on and light quality
    3 LEDs for very low watt situations.
     
    fuzzy1 likes this.
  6. wjtracy

    wjtracy Senior Member

    Joined:
    Sep 19, 2006
    10,847
    3,327
    1
    Location:
    Northern VA (NoVA)
    Vehicle:
    2006 Prius
    The long-life estimates for LED is nutty. I had a high quality Philips LED 60-w equiv bulb die in 1-yr. They gave me a refund, but what: are you going to have to save your receipts for 10-yrs to get the refund? I've got some $30 Eco smart LED's from Home Depot not failed yet but sometimes they do not go on and sometimes they flicker.
     
  7. mmmodem

    mmmodem Taste Tester

    Joined:
    Nov 17, 2011
    2,626
    1,575
    0
    Location:
    Milpitas, CA
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    I've got 3 LED's and the rest are CFL's. As each CFL bulb burns out, they will be replaced by LED. The minute wattage savings is not worth replacing a perfectly good bulb. The main reason is due to mercury in CFL. Also, there is a pollution cost to produce a light bulb. It's wasteful to constantly upgrade to the next best thing.
     
    DadofHedgehog and alekska like this.
  8. dhanson865

    dhanson865 Expert and Devil's advocate

    Joined:
    May 24, 2011
    851
    186
    0
    Location:
    TN, USA
    Vehicle:
    2005 Prius
    +1 totally agree there but I have something like 60 sockets in my house so even if I only bought a couple of LEDs a year it'd be a long, long, long time before I replaced all my CFLs.
     
  9. SageBrush

    SageBrush Senior Member

    Joined:
    Jun 4, 2008
    11,627
    2,516
    8
    Location:
    Southwest Colorado
    Vehicle:
    2012 Prius v wagon
    Model:
    Two
    I fail to see the problem, if you are happy with the CFLs.

    Home Depot would love to have your money, but that is not a very good reason to switch.
     
  10. dhanson865

    dhanson865 Expert and Devil's advocate

    Joined:
    May 24, 2011
    851
    186
    0
    Location:
    TN, USA
    Vehicle:
    2005 Prius
    I'm OK with the CFLs, I like the light level of the 9watt cfls more than the 13 watt cfls because they create less intense bright spots on TVs / monitors / tablets but I want more lumens / watt.

    Said another way what I want is to be able to buy bulbs that are more efficient than my current 9 watt and 13 watt cfls and still have choices of lumens and wattages while staying more efficient.

    All in all, I just want to save more money. I'm not looking to replace bulbs en mass, I'm looking to properly identify the switchover point and start buying LEDs.

    Currently my mix is 99% CFL, 1% incandescant, 0% LED and I will stay at 0% LED until I'm sure I'll save money by switching.

    As to home depot, I'd consider buying bulbs there but I'll also be watching Amazon and other sources.

    Bulbs I'm watching to see if the price drops include these two for the kitchen lights (recessed can socket)

    TorchStar Kirin Series LED 545 lm / 7 watts = 78 lm / watt at 7000K with 120 beam spread
    Lighting EVER 7W A19 630 lm / 7 watts = 90 lm / watt at 6000K with 120 beam spread

    and for general use

    Philips 425264 11-Watt A19 LED , Dimmable 8‚Äč30 lm / 11 watts = 75 lm / watt at 5000K
    Cree 9-Watt (60W) A19 Daylight 800lm / 9 watts = 88 lm / watt at 5000K

    I'm not sure any of these are cheap enough for me to start buying now but if they drop in price I'll probably pick up one or two.

    Personally I don't see why people are so in love with 2700K and 3000K bulbs, I'd rather stay closer to pure white. Something in the 4000K to 5000K range is fine by me. I'm not sure if I'd be happy with the 7000K bulb but if the price were cheap enough I'd try one to find out.
     
  11. FL_Prius_Driver

    FL_Prius_Driver Senior Member

    Joined:
    Jun 17, 2007
    4,319
    1,526
    0
    Location:
    Tampa Bay
    Vehicle:
    2010 Prius
    Model:
    I
    Do a mirror test. Look at your face in the mirror with the different light temperatures. That will make the reason apparent.
     
  12. SageBrush

    SageBrush Senior Member

    Joined:
    Jun 4, 2008
    11,627
    2,516
    8
    Location:
    Southwest Colorado
    Vehicle:
    2012 Prius v wagon
    Model:
    Two
    It seems clear (for now, at least) that LEDs will be the future, but for now flourescent is still leading by a long shot in the lumens/$ metric.

    I bought T8 flourescent tubes last week. $5 a piece, 90 lumens/watt, 4100k, 70s(I think) CRI, and instant on.


    As you say, LEDs of ~ 100 lumens/watt can be found, but there is a wide range that tends to parallel flourescent. I was a bit surprised to find a fancy display of LEDs by Sylvania being displayed in a kiosk last week that had 45 - 50 lumens/watt.

    I'm personally looking forward to the day I can buy $5 LEDs that have 450 lumens/3 watts.
     
  13. mmmodem

    mmmodem Taste Tester

    Joined:
    Nov 17, 2011
    2,626
    1,575
    0
    Location:
    Milpitas, CA
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    For me, it's not about the savings in cost that is driving the change to LED. In fact, it's quite the opposite. CFL's are subsidized by the utility company down to $0.25 a bulb. I haven't done the cost analysis but I'll go out on limb and say I just might not recoup that kind of cost versus a $10 LED. I'm doing the change for health and environmental reasons. The increased cost is easy to stomach at the slow rate my current bulbs are going out.

    $5 LED bulbs started circulating recently. I'm wary of the quality, though. My original CFL purchased with gobs of money maybe a decade ago is still working. The cheap ones not so long.
     
  14. SageBrush

    SageBrush Senior Member

    Joined:
    Jun 4, 2008
    11,627
    2,516
    8
    Location:
    Southwest Colorado
    Vehicle:
    2012 Prius v wagon
    Model:
    Two
    mmmodem,

    I hear you re: environment and health; and in general I think LEDs are awesome and have tremendous potential. I'm just skeptical of any real reason to only consider LED today Vs flourescent.

    Health boils down to Hg. I at least do not dump these bulbs in my trash, and instead bring them to authorized disposal centers. So as long as the Hg is being recycled I am not adding to the problem. I'll agree that if society at large is handling the Hg poorly then that is a very good reason to phase them out.

    Environment does not pan out because of opportunity cost. It just makes sense to spend one's green $ for the best green ROI.
     
  15. dhanson865

    dhanson865 Expert and Devil's advocate

    Joined:
    May 24, 2011
    851
    186
    0
    Location:
    TN, USA
    Vehicle:
    2005 Prius
    Eat a food with no salt or a ton of salt on it. The difference will be apparent.

    Doing anything at one extreme or the other isn't a good idea just because some people are used to it.
     
  16. FL_Prius_Driver

    FL_Prius_Driver Senior Member

    Joined:
    Jun 17, 2007
    4,319
    1,526
    0
    Location:
    Tampa Bay
    Vehicle:
    2010 Prius
    Model:
    I
    Whoa, what I intended got misinterpreted. The "mirror" test was to show how lower temperature bulbs make faces look more appealing. There was absolutely no personnel inference intended, it was just intended as a simple example of why many folks like the the lower temperatures. My bad.
     
  17. dhanson865

    dhanson865 Expert and Devil's advocate

    Joined:
    May 24, 2011
    851
    186
    0
    Location:
    TN, USA
    Vehicle:
    2005 Prius
    If you thought I misinterpreted your statement as a jab at the lack of beauty of my face worry not. I've seen many photos and videos of people looking into a mirror with different light bulbs lighting their face and know the effect you were referring to.

    My contention is that too low k bulbs are just bad in a different way that too high k bulbs.

    Everything in moderation.

    The thing is with salt you can add as little or as much as you like. When you go to buy a light bulb many types only offer one or two color temperatures.

    If I see two bulbs on the shelf and the choice is 2700k or 3000k but I really want something with a higher k it isn't much of a choice. I'll buy the 3000K and be less unhappy with it than I would be with the 2700K.

    Until a major bulb manufacturer makes 3 or more color temps in the same style bulb you'll only see people grabbing the "yellowish" or "warm" one because they are used to it. Give them 3000K, 4000K, 5000K and watch how many people grab the middle choice and say they are happy with it.

    hope my response makes more sense now also, I had no qualm with how you wrote that post.
     
    FL_Prius_Driver likes this.
  18. ChapmanF

    ChapmanF Senior Member

    Joined:
    Mar 30, 2008
    9,048
    6,604
    0
    Location:
    Indiana, USA
    Vehicle:
    2010 Prius
    Model:
    IV
    How about 2700, 3000, 4000, 5000 so we have a choice of a middle one that isn't icy?

    What I personally have is 2700s everywhere except a 3000 at my desk. The 3000 is nice for desk work and makes an attractive but subtle contrast to the rest of the room.

    I've seen plenty of living spaces lighted with 4100 or higher and personally it just sets my teeth on edge to be in them. Also I have a friend who had 4100 fluorescents in the kitchen and never knew how nice the wood cabinetry could look until those were changed.

    Some of it could be generational; remember I grew up not only with incandescents at 2700, but incandescents on dimmers (which drop even further in color temperature when you want that cozy mood, as opposed to dimmable CFLs which just give you less of the same color). We also thought it cozy to sit around the fireplace. Partly what you're used to, I guess.

    -Chap
     
  19. dhanson865

    dhanson865 Expert and Devil's advocate

    Joined:
    May 24, 2011
    851
    186
    0
    Location:
    TN, USA
    Vehicle:
    2005 Prius
    1. what you are used to / what you grew up with, yep I believe I mentioned that above.

    2. You saw bad lighting labeled 4100k? Maybe because

    a. it was because of 1.

    b. it was truly bad lighting (low CRI or mislabeled as 4100K when it was really 7000K or some other issue)

    either you just need time to get used to good lighting or you don't understand how yellow 2700K is.

    While different sites reference pure white at differing K values I think the image below is a good enough to get the point across on how far down the scale your 2700/3000K bulbs are.

    [​IMG]
     
  20. SageBrush

    SageBrush Senior Member

    Joined:
    Jun 4, 2008
    11,627
    2,516
    8
    Location:
    Southwest Colorado
    Vehicle:
    2012 Prius v wagon
    Model:
    Two
    Interesting discussion, Dhanson.
    I also find myself thinking of fluorescent as whitish-blue, but perhaps I am blinded by preconception, or other aspects of light that play into the question.

    Found this related to natural sunlight:
    Before sunrise: 10,000 degrees K
    Before sunrise the only illumination comes indirectly from a blue sky. This produces a characteristic strong steel blue color.
    Dawn: 2,000-2,500 degrees K
    The lighting will change to a very warm red color just as the sun comes up. Look for the first appearance of shadows.
    Early morning: 3,000-4,000 degrees K
    The color temperature will become more neutral as the sun continues to rise through the morning.
    Midday: 5,500 degrees K
    Overhead sun at noon produces neutral colors, though this may not be best pictorially.
    Overcast: 7,500 degrees K
    Overcast lighting conditions raise the color temperature noticeably. Your photographs will have much cooler colors.
    Shade: 10,000 degrees K
    The color temperature in shade on a sunny day is extremely high. All of the lighting will be coming from the blue sky.
    Afternoon sun: 3,000-4,000 degrees K
    The color temperature will fall as the sun goes down. The light effects become warmer and redder.
    Sunset: 2,000-2,500 degrees K
    Some of the reddest lighting conditions of the whole day will be at sunset.
    Twilight: 10,000 degrees K
    Just after sunset, the lighting will suddenly becoming very blue, for the same reasons as the shadows above.
     
Loading...