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Old 03-17-2011, 04:38 PM   #16
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from some website..

How much does a light bulb cost?

There is of course, an easy answer to this… It costs whatever the sticker on the box says. On the other hand, there are two other costs associated with a light bulb.

1) Replacement cost. A light bulb is no good if it doesn’t last. In the long run, a $5.00 light bulb that lasts for 100 hours is cheaper than a $1.00 light bulb that lasts for 10 hours.

2) Energy cost. You’d probably like your light bulb to light, and for that you need energy. Energy consumption is measured in kilowatt hours. If you burn a 60 watt bulb for 1 hour, you’ve consumed 60 watt hours or 0.06 kilowatt hours of power (remember, kilo = 1000). Since the electric company charges you for every kilowatt hour you consume, a bulb that uses less power may also be cheaper in the long run than a bulb with a lower sticker price that consumes more energy.





Please note: When people think about bulb wattage, they usually think that it is a measure of light intensity. In actuality, light intensity is measured in lumens. A typical 60 watt incandescent bulb produces about 800-900 lumens of light. A typical 100 watt incandescent bulb produces closer to 1700 lumens.

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Old 03-18-2011, 08:54 AM   #17
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There is one factor missing on this economic justification -- effect on heating and cooling. In the winter, changing from halogen to LED has less benefit, because all that extra energy used by the halogens simply becomes heat anyways. In most places, oil or natural gas is somewhat less expensive than electricity, but you will be running your furnace that much longer to make up for the heat not being given off by the lights. In the summer the opposite is true, with halogens, first you pay for the electricity to run them, then you pay for the electricity to run your air conditioner to pump that heat out of the house. So in Pheonix, you are going to have an easier time justifying the cost of LED's than you will in Michigan
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Old 03-18-2011, 09:06 AM   #18
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Originally Posted by SPS-1 View Post
There is one factor missing on this economic justification -- effect on heating and cooling. In the winter, changing from halogen to LED has less benefit, because all that extra energy used by the halogens simply becomes heat anyways. In most places, oil or natural gas is somewhat less expensive than electricity, but you will be running your furnace that much longer to make up for the heat not being given off by the lights. In the summer the opposite is true, with halogens, first you pay for the electricity to run them, then you pay for the electricity to run your air conditioner to pump that heat out of the house. So in Pheonix, you are going to have an easier time justifying the cost of LED's than you will in Michigan
They get warm, but I didnt think they gave off that much heat They're installed in the ceiling of my basement, under the subfloor for my house. Maybe in the winter I'll leave them on and heat my floors
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Old 03-19-2011, 07:51 PM   #19
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If they are all turned on, that 1650 watts right?
That energy ia ALL heat.
Almost all of that energy is immediately produced as heat. The small amount of energy that becomes light, will be converted to heat when the light is absorbed by the stuff in that room. Of that 1650 watts, the only energy that does not become heat in your house, is light that escapes through the window, but that is an extremely small proportion.

(Before somebody corrects me, to be specific Watts is power, but power x time = energy)
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Old 03-21-2011, 08:20 AM   #20
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Does someone want to do the math on a 50W halogen and the equivalent lumen producing LED which I believe is a 4W, considering the initial cost of each bulb? Will you ever recoup the cost of the more expensive LED?
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Old 03-21-2011, 08:36 AM   #21
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Does someone want to do the math on a 50W halogen and the equivalent lumen producing LED which I believe is a 4W, considering the initial cost of each bulb? Will you ever recoup the cost of the more expensive LED?
I did. For a decent LED is about $30 at this time. A crappy one that you'll be disappointed in costs about $10. In my case, using the lights for only a few hours a day would take me 5 years and 5 months to break even on the initial cost. Obviously if these lights will be used regularly, the initial cost will be recovered much quicker.

Im all for saving energy, and being as "green" as possible, when it makes sense to do so. If this were the main living area of my home, I wouldnt have a second thought about making the switch.
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Old 04-09-2011, 11:14 PM   #22
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maybe to little to late however the cost to replace 30 halogens can be pretty expensive.. LED will "never" have to be replaces. that is something that should be figured in as well.
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Old 04-09-2011, 11:33 PM   #23
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maybe to little to late however the cost to replace 30 halogens can be pretty expensive.. LED will "never" have to be replaces. that is something that should be figured in as well.
if that's the case, then we are going to have to start doing actuarial studies to see how long the owner is going to live so we know how many incandescents they won't have to be replacing.
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Old 04-10-2011, 12:23 AM   #24
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good point.. we need ALL information Pertinent to said study to be posted so that we can attempt to determine how long you will live to see if the cost savings is really there.

seriously though halogens life span About 2000 hrs LED lifespan About 50,000

http://eartheasy.com/live_led_bulbs_comparison.html

sorry no halogen in there but spells out what im trying to say. in relation to cost of bulb replacement.
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Old 04-10-2011, 02:17 AM   #25
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I'm surprised not to see much mention of dimming here... for me it's a dealbreaker. I would love to have LED bulbs or even CFLs, but until the quality of light and dimmability issues are solved, the extra cost is hard to justify. I use efficient bulbs/fixtures wherever the lights serve a utility function, but when it comes to nice living space lighting, the ability to control the mood of the room with a dimmer (and saving some energy while you're at it) is just not optional.

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