Energy

Affordable Mass Market LED Lights on the Way

By Ryan McGreal
Published February 23, 2007

(this article has been updated)

The folks at treehugger just reported that a company in The Netherlands has launched a new LED light, called the "Pharox", which generates as much light as a 40 watt bulb but uses only 3.4 watts.

A pack of four costs € 22.68. That's $8.63 Cdn per bulb.

Granted, that sounds like a lot of money, but as always with these matters, it's important to pay attention to the lifecycle costs, not just the initial capital cost. A three-way comparison between LEDs, compact fluorescent lights (CFL) and incandescent light bulbs (ILB) is in order.

Purchase Costs

Because LEDs and CFLs have a much longer lifespan than ILB, we need to calculate the lifetime costs of replacing the lights. Let's start with LEDs, which have the longest lifespan. Because the LED actually produces less light than the other two, I bumped the price up to an even $10 for the sake of comparison.

Energy Costs

So far, LEDs are ahead. However, we also have to calculate the lifetime energy costs of operating the lights.

For the sake of this example, I used $0.10 per kilowatt-hour. Bear in mind that over the next twenty years, that price is ridiculously optimistic; we will more likely be paying at least triple that price, either directly in our hydro bills or indirectly through tax subsidies.

Note: the featured LED is 3.4 watts but only produces light equivalent to a 40 watt bulb. For the sake of comparison, I calculated that an LED producing light equivalent to a 60 watt bulb would require 5.1 watts.

So:

Total Costs

Now we can add up the purchase price and usage price for each light over 60,000 hours to get the total price.

Light Types Total Cost Comparison
Light Purchase Price Usage Price Total
LED $10.00 $30.60 $40.60
CFL $60.00 $96.00 $156.00
ILB $30.00 $360.00 $390.00

Over the 60,000 hour life of an LED light, you'll save $115.40 compared to CFL, and $349.40 compared to ILB. Hmmm, tough decision.

Update: A reader noticed that my summary table erroneously listed the total purchase costs of a CFL as $10 instead of $60. I've corrected this. Thanks for pointing it out! - R.

Update 2: A few commenters have suggested that $10 per CFL is too much money. The last time I bought CFLs was a couple of years ago and they were that much back then. For the sake of argument, I re-calculated the Cost Comparison based on $3 per CFL. Replace six times, that works out to $18.

Light Types Total Cost Comparison, $3/CFL
Light Purchase Price Usage Price Total
LED $10.00 $30.60 $40.60
CFL $18.00 $96.00 $114.00
ILB $30.00 $360.00 $390.00

As you can see, at $114 total cost, CFL is still considerably more expensive.

Ryan McGreal, the editor of Raise the Hammer, lives in Hamilton with his family and works as a programmer, writer and consultant. Ryan volunteers with Hamilton Light Rail, a citizen group dedicated to bringing light rail transit to Hamilton. Ryan writes a city affairs column in Hamilton Magazine, and several of his articles have been published in the Hamilton Spectator. He also maintains a personal website and has been known to post passing thoughts on Twitter @RyanMcGreal. Recently, he took the plunge and finally joined Facebook.

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By user (anonymous) | Posted February 23, 2007 at 12:16:03

In the table "Light Types Total Cost Comparison" the purchase price for CFL should be $60 not $10, bringing the total for CFL up to $156

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By Ted Mitchell (registered) | Posted February 23, 2007 at 12:33:34

Good analysis! But many raise the issue of the quality of light produced.

Basic incandescent light bulbs are pretty bad for CRI (color rendering index). This is a 0-100 scale where 0 is black and white and 100 is the quality of color produced by noon sunlight. Some people wrongly list all incandescents as "100" because their radiation is of the "blackbody" variety. At a much lower temp than sunlight a much redder spectrum is produced. Typical cheap ILB's rate about CRI 80 (they are very yellow).

Much better is the neodymium glass bulb (e.g. GE Reveal). This is a typical IDL filament perhaps burning slightly hotter (shorter life), with different glass around it. There is no sign of yellow light, it appears white. The CRI is 90+. If you haven't tried one, do it.

4 foot flourescent tubes have both a color temperature and CRI rating. E.g. 2800K means this is approximately the color of a filament at this temperature (fairly red light). 5000K is like typical sunlight. 6500K is equatorial noon sunlight (will look very bluish is the brightness is less than sunlight), etc.

CRI is typically 70 or less for "cool white" which is also 4100K. STAY AWAY FROM THIS CRAP. Most people have no idea that these are obsolete.

The T12 "cool white" can be replaced directly with a T8 3500K CRI 85 bulb (called "835": 8 is the CRI decade, 35 is for 3500K) which is actually the same $2 price, but even MORE efficient and has better color rendering than a typical IDL.

The best CRI you can get easily is the "sunlight" bulb, either a T12 5000K CRI 90 or the better T8 5000K CRI 95, both about $6. These use expensive phosphors that are also slightly less efficient than the 8 series (CRI in the mid 80's)

CFL's do not have these numbers listed or even available. So maybe they might be 2800K and CRI 82 like a typical IDL, or maybe something much worse. Probably not better though, even though this is well within current technology.

LED, who knows? Certainly the LED flashlights I have are quite bluish and likely poorly rated for CRI. But there is certianly a lot of potential there.

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By sewiv (anonymous) | Posted February 23, 2007 at 14:16:26

There's an error in your table. The CFL Purchase Price should be $60, giving a total of $156.

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By Spiff (anonymous) | Posted February 23, 2007 at 16:23:43


The problem with this analysis is time value of money. Full time jobs are 2,000 hours per year. If we kept a bulb on during working hours, a 60,000 hour bulb could easily last 30 years.

But this comparison treats money to buy incandescent bulbs bought 30 years from now the same as money to buy led bulbs today.

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By gerryscat (anonymous) | Posted February 23, 2007 at 17:07:07

Your prices are WAY, WAY, WAY off. I just bought 3 CFL's for about $10 Canadian, or about $8.50 US.

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By Number33 (anonymous) | Posted February 23, 2007 at 17:25:33

As for the comments above on CRI, CRI only tells you how far a light deviates from the blackbody curve AT A GIVEN COLOR TEMP, it can't be used to compare lights of different color temp. So incandescent are 100 CRI by definition, but that doesn't mean their color rendering is realistic. When most people say that color from CFLs looks bad, they're genereally referring to 2700K CFL designed as an incandescent "look-alike", I agree that those generally look terrible. CFLs in the 3500-4100K range (if you can find them) have both higher CRI and a more useful color temp. It's important to note though that the higher the color temp, the brighter the light you need for it to look good.

As for the LEDs -- no way are they anywhere close to a 40W incandescent for light output. The most efficient LEDs on the market right now, Cree XR-E (5500-6500k, around 84 CRI, good lights but definitely not "warm white"), are about 100 lumens per watt when underdriven and heatsinked. Accounting for optics losses and ballast losses this light might be able to put out around 300 lumens if they're using the best LEDs on the market. (I doubt they are using LEDs this efficient anyway since they didn't explicitly state any lumen numbers)

Realistically I expect this light is probably under 200 lumens. A typical 40W bulb is about 480 lumens, and a typical 9W CFL (Available for $2.50 at Home Depot) is over 500 lumens.

While I think LEDs have great potential for replacing halogen spotlights (since LEDs can be focused efficiently) they won't be able to compete for good electronic ballasted fluorescent for area lighting. Two T8 tubes in a highly efficient reflector can put out almost 5000 lumens from the fixture from 64 watts of power, and about $35 up front. (A 65W reflector bulb puts out only around 700)

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By gwb (anonymous) | Posted February 23, 2007 at 18:26:11

Did you know there's an error in your math? Just in case you missed the 100 other entries pointing it out. It should be $35T instead of $3.5B.

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By kenmce (anonymous) | Posted February 24, 2007 at 16:18:09

Pharox is the first 3.4 watt LED lamp with a light output which can be compared to a standard 40 watt (flame) light bulb.

You will note that they use a rather odd unit to measure its light output. Is a "flame light bulb" one of those incans with a flickery orange filament that is supposed to resemble a candle?

To do a proper comparison you need units that emit equal amounts of light, and Pharox doesn't actually say how much light they emit.

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By Ted Mitchell (registered) | Posted February 25, 2007 at 17:21:14

question for number33 or anyone - why do manufacturers not list CFL color temp or CRI when this info is easily available for straight tubes?

i've tried websites and emails to no avail.

no wonder that many people are disappointed with CFLs when they have no idea what they are buying.

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By CFL - LED (anonymous) | Posted February 26, 2007 at 09:19:57

CFL's are as low as $2 a bulb nowadays, and not $10 a bulb.

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By dendubs (anonymous) | Posted April 11, 2007 at 14:02:06

I want to also point out the after effects of using florescent bulbs, a big one. They contain mercury in minute amounts. add it up. The manufacturing process makes LED's #1 in my book

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By Remi (anonymous) | Posted May 10, 2007 at 00:07:16

One other thing to consider is Lumens per watt or light production per watt... As far as I know, LEDS are only able to produce something like 55 lumens/watt, while fluorescent something like 70 lumens/watt and high pressure sodium (street lights) 120lumens-watts. I`m sorry I`m not giving sources for my info but i`M confident my numbers are in the right ballpark. If the last research I saw is correct the latest 30$ led bulb would only be able to produce the same light as a 40 watts ILB while you can get a 100 watt ILB equivalent for 3$ in fluorescents...LEDs do last longer though and potential is very high as I think I`ve seen prototypes of 150 Lumens/watt in LEDs, but right now Fluorescents are still king in my appartment.

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By scobb (anonymous) | Posted May 17, 2007 at 17:56:25

Ryan--you're a brave guy to put these numbers forward for folk to pick at. They are certainly numbers we all should be researching right now. Like a lot of guys, I live with someone who does not like fluorescents (my wife) and I would love to use LEDs because of their low power and high longevity. But for me it boils down to the lumens.

A 60-watt incandescent and a 18-watt fluorescent both give off about 1000 lumens. I haven't been able to find a commercially available LED "bulb" with more than 100 lumens. If you've seen a computer projector doing PowerPoint slides at 1000 lumens then the idea of one tenth the light of that is not very appealling. Nevertheless, I plan to replace the the bulbs in my desk lamps with LEDs just to get started.

Stephen Cobb
cobbontech.blogspot.com

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By kunle (registered) | Posted May 22, 2007 at 04:09:08

Pls can anyone in help compute the amount of Lumen that a flourescent light produces as the same as amount of lumen of Kerosene lamp. or what is the Lumen of Kerosene lamp. thanks kunle

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By Sarah (registered) | Posted June 27, 2007 at 10:18:27

If you check the website, the cost of the LED bulb is 22.68 Euros per bulb, not per 4.

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By Alex (registered) | Posted July 23, 2007 at 12:11:27

I have been checking out fluorescent tubs and compact fluourescents that have a CRI of 96 (5900 K)from www.fullspectrumsolutions.com Their new T5s are rated at 5200 lumens. They put out a ton of light. They make other fluorescents look brownish. Have any of tried them - have an opinion on them?

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By mickrussom (anonymous) | Posted July 24, 2007 at 00:56:36

Everyone here pushing CF you are forgetting that using CF and poisoning the world means murder in the first degree. It violated ROHS and is genocidal, autism is 1/160 births and mercury and other ROHS banned metals are partly to blame. Again, CF = murder. Hg = murder. CF should have been banned, mercury in any home appliance should be banned.

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By seancb (registered) - website | Posted July 24, 2007 at 14:12:06

CF as with all hazardous materials should be disposed of correctly. It would be beneficial to have a municipal program for regular collection of batteries, bulbs and other hazardous goods -- if it's not convenient, people won't do it. CF and other hazards ending up in the trash is purely a result of laziness.

Mick, I'd be interested to have a peek at the products and services you surround yourself with. There are so many hazardous chemicals used in manufacturing so many things that is impossible to live completely impact-free. If everyone burned candles for light, we'd be no better off (albeit the issues would be different than with CF).

I hate to break it to you, but by being humans we are by definition "murderers" in that we consume resources and create waste -- we have no choice but to cause a detriment to SOME creature SOMEwhere. So we have to choose our battles. Do you have an alternative to CF that you can suggest?

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By mickrussom (anonymous) | Posted July 28, 2007 at 17:31:05

LED lights could be used. ROHS compliant materials are a step in the right direction. Im sorry, seancb, that you are ok with autism, and poisons and pollution, but I am not. There are programs in the US and EU, like ROHS, that are a step in the right direction. Saying being human means that its ok to dump mercury in the environment is a total cop-out. And its wrong.

LED lights, like the Pharox bulbs for Oxxio customers, are being blocked or lobbied against by GE or other CF-mudercury manufacturers wants profit over making bulbs safer and more efficient.

Its sad we live in a world where the technology exists to be cleaner (Nuclear, wind power, LED bulbs, etc) , but people simply ignore it.


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By Prince (registered) - website | Posted December 21, 2007 at 04:55:31

I fabricated a LED unit using 144 LEDs and that gives out a good powerful light more than 60W bulb I think. It cost around US$20 for the lot. Here in India, and uses 12W of current. As someone else said its a focussed light. I have used it in my marine fish tank, But I think I should get one more fabricated to provide suffcient light. ts cheaper than using Metal Halide 150W and cheaper to use at 12W. Although they say that the pure white LED provides 8000-10000 Kelvin I'm not too sure. The MH gives me 12000K and thats the way to go for a marine fish tank. I wouldn't consider the expense for other applications as there is no comparison in initial cost.

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By calsolar (anonymous) | Posted January 25, 2008 at 20:02:49

The 60000 hr comparison may not be compelling for people because it's hard to project that far. At 3 hours per day, that's about 55 years. Anyone lived anywhere that long, let alone have a light fixture that old? And as pointed out previously it ignores the time value of money.

It is probably better to look at how long it takes for the LED to pay for itself with savings.

Assume the ILB is free (it's already in the fixture). Assume all the replacements are free (you get the ones people are replacing with CFLs). At $0.10 per kwh, and assuming a 40 watt bulb, it takes 25 hours of operation to use a kwh. So the bulb costs you $0.004 per hour.

If the LED cost $40, and uses 4 watts, it costs $0.0004 per hour.

So what's the payoff time? H hours

IFL cost = H x $0.004
LED cost = $40 + H x $0.0004

Equating

$0.004 H = $40 + $0.0004 H

($0.004 - $0.0004) H = $40

H = 40 / 0.0036

H = 11,111 hours

So if you use the light 3 hours a day, it will take 3703 days or roughly 10 years for simple payback, so even longer when considering NPV.

If you use it 24 hours a day, it will take 462 days or a little over a year.

This gives you a feel for the dynamics. Lights used a lot make a lot more sense to replace. Your closet light just doesn't matter that much (CFL or ILB or LED) unless you leave it on all the time. It doesn't use that much electricity and it doesn't produce that much carbon.

If you live in Hawaii, your electricity costs 3x as much, so the time is cut to a third. 24 hour a day lights (traffic lights, emergency exit lights) are going to pay for themselves in a few months and keep paying.

If the LEDs cost 1/2 what I assumed, the payoff time is 1/2. If 2x as much, then payoff time is twice.

If it costs you to replace those bulbs every 1000 hours (office building or parking garage) you can include that cost and LEDs get better.

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By Q (anonymous) | Posted July 26, 2008 at 12:45:50

Just a note for anyone interested. The WalMart near me (Englewood Ohio) has 40Watt equivilent LED lights with a standard socket for $5.82 each. Not sure if that is a one time purchase because they have not restocked in the last 4 weeks. I bought what I could when they were available. I agree they are probably not a full 40Watt equivilent but the price is much lower than what I've seen posted here. I wait for sale prices on bulbs so my typical cost of a CFL is $2.00 (Menards sale price) and I buy only the daylight bulbs as they have a much whiter light. As far as the mercury debate.... CFL's will be taken off of the market in a few years when LEDs become cheaper so the trade off is in more murcury now in limited amounts vs. More polution from non clean forms of energy production. I will not be throwing my CFL's into landfills so I don't believe I'm contributing to MURDER as some would have you believe. I also take the time to educate others on the CFL's and the murcury hazard and how to minimize the risks to themselves and others. I'm all for a clean environment so I will buy the most cost effective choice and hope that LED technologies hurry to catchup so the prices fall.
Remember to add some logic into your scare tactics so you don't come off as a nut case in future postings. More folks might listen to you and help with your cause (including myself) if you stick to the facts and let us be the judge of our actions. Just my 2 cents.

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By Q (anonymous) | Posted July 26, 2008 at 13:34:46

Just a note for anyone interested. The WalMart near me (Englewood Ohio) has 40Watt equivilent LED lights with a standard socket for $5.82 each. Not sure if that is a one time purchase because they have not restocked in the last 4 weeks. I bought what I could when they were available. I agree they are probably not a full 40Watt equivilent but the price is much lower than what I've seen posted here. I wait for sale prices on bulbs so my typical cost of a CFL is $2.00 (Menards sale price) and I buy only the daylight bulbs as they have a much whiter light. As far as the mercury debate.... CFL's will be taken off of the market in a few years when LEDs become cheaper so the trade off is in more murcury now in limited amounts vs. More polution from non clean forms of energy production. I will not be throwing my CFL's into landfills so I don't believe I'm contributing to MURDER as some would have you believe. I also take the time to educate others on the CFL's and the murcury hazard and how to minimize the risks to themselves and others. I'm all for a clean environment so I will buy the most cost effective choice and hope that LED technologies hurry to catchup so the prices fall.
Remember to add some logic into your scare tactics so you don't come off as a nut case in future postings. More folks might listen to you and help with your cause (including myself) if you stick to the facts and let us be the judge of our actions. Just my 2 cents.

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By mr led (anonymous) | Posted October 05, 2008 at 11:41:14

a few points of info to help.local stores like home depot are now doing cfl recycling centers.please call your local stores to see if they taking back failed bulbs.in the next 3-6 months from cree led and other vendors led that have the same white light as standard bulb and one chip led bulbs (20w) with same lighting as a 100w bulb and the price point of a cfl blub as most of the big three blub makers have switch over to led plants.

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By BENNIBOB (anonymous) | Posted October 16, 2009 at 07:21:48

h.t.t.p://www.ledlight.com/t12-t8-led-tube-light-4foot-15-watt.aspx

REMOVE "...."

h.t.t.p://www.ledlight.com/8-2-watt-led-light.aspx

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By ledwallwasher (anonymous) | Posted November 03, 2010 at 12:41:39

Light fixtures need to improve efficiency
http://www.leledlighting.com

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By Sarah (registered) | Posted June 03, 2011 at 04:06:40

Hi, we are the factory in China, specialized in LED lamps, LED tube, spot light etc. Please visit our website www. firstled.net, or contact firstled@163.com for detail.

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