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Best lighting cost comparison: Incandescent, CFL, LED

LED, Incandescent, CFL

LED, Incandescent, CFL

Between Incandescents, CFLs, and LEDs, there are many different lighting options available for the homeowner.  The problem is that there are so many options, the energy-saving technology keeps improving, and costs keep adjusting.  I've done a cost comparison between incandescents and CFLs that showed how much better an investment CFLs were.  Since then, a few models of LEDs are available for the home and I have now included them in a cost comparison.

Until someone proves me wrong, I'm convinced the spreadsheet below is one of the best lighting cost comparisons on the web.  I've put in some reference data for each bulb so you can verify the data.  For the incandescent, I included a GE long-life 60-watt bulb.  I'm using the n:vision CFL's I use in my house which are still working flawlessly and out of probably 15 bulbs I haven't had 1 failure in 1.5 years.  Finally, for the LED I'm comparing the newly released Pharox60, 6 watt dimmable LED by Lemnis Lighting and Digital Light. Update - 2/10/11 - I've updated the sheet with more recent data.  Home Depot changed the n:vision brand name to EcoSmart.  I'm using EcoSmart bulbs for both CFL and LED because I can easily get them at Home Depot and I've been happy with the quality so far.  The EcoSmart A19 LED I'm testing out is about 30% cheaper than the Pharox60 LED and has a higher light output.

The cells in yellow are meant to be edited by you based on your situation.  The cells in green are current prices for the lights I'm comparing in the sheets.  If you find better prices or want to compare different lights, adjust these prices accordingly.

[iframe_loader src="http://sheet.zoho.com/public/ckmapawatt/lighting-cost-analysis" height="400" width="800"]

The first thing to notice is the Lumens (light output) of each bulb. The CFL uses less energy than the incandescent, but puts out more light! And while the LED uses less energy than the other bulbs, it puts out 2.5 times less light than the CFLs!  According to my sheets, it would take almost 30 Years before a current investment in an LED bulb would turn out to be the better investment over a CFL.  Now, that's based on an electricity price of $.010/kWh, and if you pay more than that, LEDs look a little more attractive.

Since LEDs have such a high initial cost, it is very hard to re-coup that cost over the life of the bulb.  The other issue is how much less light they put out compared to the incandescent or CFL.  What I will say is that if you are reluctant to adopt CFLs in your house due to concerns over mercury (even though it is a very minuscule), then the LEDs could be a great alternative to incandescents.  Since incandescents use so much electricity (most of the energy that goes into them turns into heat), the payback of an LED at .10 cents per kWh is around 5 years when compared to the incandescent.

The important thing to take away from the sheet is how bad a monetary investment incandescents are and how much energy they use compared to CFL and LED technologies.  It's time to get away from 100 year old energy-wasting technology and start saving your home money and helping to waste less energy!

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Comments

I have been using CFL's since they first came out but am about to change my ways. It takes energy to produce the CFL's, energy to get them to the shelf and more to move them to my home where they quickly burn out. They cost more than the standard incandescent but don't last half as long and many provide less than adequate lighting. I'm ready to try the LED's which should drop in price as volume increases.
ckmapawatt's picture
Rosaleen, Which brand of CFLs are you using? They may just be cheaply made. I do agree with you on LEDs though. The LED I'm testing out has performed wonderfully and it was only $10 (with the cost dropping constantly).
Are we all so caught up in feeling good about being "Green" that we completely negate the future feelings of what it will be like to pay more for drinking water than we do for gasoline? That's right everyone, Mercury is a poison. Perhaps Edison was right in the first place? CFL's are what happen when you allow government to run your lives. Good luck with all your "Feelings" of saving the planet. Such small thinkers, tisk tisk. I am burning all incan's and have enough stashed away to last me a lifetime. One thing for certain I will be greener than all of you CFL lovers.
ckmapawatt's picture
Hey Jackson....do tell me what part of the country you live in? Unless it's the Northwest, I'm guessing the majority of your electricity comes from coal. From this link from <a href="http://www.popularmechanics.com/home/reviews/news/4217864" rel="nofollow">Popular Mechanics comparing Mercury emitted from incandescent vs. CFLs</a>: <blockquote> About 50 percent of the electricity produced in the U.S. is generated by coal-fired power plants. When coal burns to produce electricity, mercury naturally contained in the coal releases into the air. In 2006, coal-fired power plants produced 1,971 billion kilowatt hours (kwh) of electricity, emitting 50.7 tons of mercury into the air—the equivalent amount of mercury contained in more than 9 billion CFLs (the bulbs emit zero mercury when in use or being handled). Approximately 0.0234 mg of mercury—plus carbon dioxide, sulfur dioxide and nitrogen oxide—releases into the air per 1 kwh of electricity that a coal-fired power plant generates. Over the 7500-hour average range of one CFL, then, a plant will emit 13.16 mg of mercury to sustain a 75-watt incandescent bulb but only 3.51 mg of mercury to sustain a 20-watt CFL (the lightning equivalent of a 75-watt traditional bulb). Even if the mercury contained in a CFL was directly released into the atmosphere, an incandescent would still contribute 4.65 more milligrams of mercury into the environment over its lifetime. </blockquote> Don't be so smug next time.
There you go again Chris, with the same uneducated reply... There is something just a bit hypocritical in stating that the carbon footprint of CFLs is less than that of incandescent light bulbs, if one looks at the manufacturing processes of both. Incandescents have a much shorter material list than CFLs. Also factor in the cost of special cradle-to-grave handling and disposal/recycle for CFLs, besides the labor involved in twisting the glass by hand, manufacturing, gathering and soldering the discrete electronic components and hazards involved in coating the glass with phosphors and adding the mercury and other toxic gasses. No CFLs are manufactured in the Americas or Europe. Why? The health standards for manufacturing are not as strict. All are manufactured in either China or India. Factor in overseas shipping and handling expenses. Now that you have that long list, figure the carbon footprints. Incandescents are becoming more efficient as well (GE ceramic technology from 2007). At the moment, incandescents create 5-10% light and 90-95% of the energy input goes to heat. With CFLs, 25% of the energy input goes towards making light and 75% goes to heat. CLFs are between 10-15% more "energy efficient", while using as much as 75% less electricity, using sophisticated electronics. The total energy input for the production of a CFL light bulb comes to 1.7kWh compared to 0.3kWh for a single incandescent light bulb. Note: Not included in the manufacturing costs for CLFs are the mining of materials associated with the various phosphors or the mercury. Nor are transportation costs factored in (imports). "8 grammes of waste are produced in the manufacture of the incandescent, but 128 grammes are produced in the manufacture of a Compact fluorescent of which 78 grammes are hazardous." (Original information derived from spreadsheets prepared for the European Parliament Energy savings committee.)
One thing I notice in all the posts is the fact that no one has mentioned the electromagnetic radiation emitted by the CFL bulbs,it is high compared to the other bulbs and does have a negative effeft on the body,especially if sitting close to the bulb.Something to consider in your choice of lighting.
ckmapawatt's picture
Ken, I haven't much looked into that issue. Do you have any information or links to other sources?
I have looked into it because I do some research before I go drinking the kool-aid...and I'll be quoting...from my research. "Most CFLs have a claimed power factor of around 0.52 (where the figure is given at all), so a 15W CFL will actually draw just under 29VA. Because the load is not linear, the current waveform is in phase with the applied voltage, but is discontinuous. This simply means that current is only drawn at the peak of the waveform, and this effect causes a poor power factor just as readily as a phase shift between voltage and current. The nasty waveform created by CFLs is another thing that is going to come back and bite us on the bum. Any spike waveform means that significant harmonics are added to the mains waveform, and although CFLs are only a small percentage of 'nasty waveform generators' at present, the situation will get a lot worse. An anecdote on the power factor issue was sent to me ... Apparently a company in the UK installed a large number of CFLs in a building where the lighting was primarily on one phase. It burnt out the neutral link in the fuse box and caused a small fire! The high peak current of all non-power factor corrected CFLs can cause problems where they are used in large numbers. For example, 25 x 75W (incandescent) lamps will draw 7.8A - just within the 8A rating for lighting circuits in Australia. The power factor is 1 because of the resistive load. If replaced by 25 x 13W CFLs, although the RMS current is lower, the peak current is over 10A (based on the 410mA peak current). No problem at all so far, but ... What if the installer decides that many more lamps can be connected to the circuit because of the lower power? Based on the claimed RMS current for a typical 13W CFL (~95mA is typical), it would seem that you can run 80 CFLs on the same lighting circuit (80 x 95mA = 7.6A). Unfortunately, the peak current is 80 x 410mA = 32.8A. The wiring won't overheat, but in-line connections (junction boxes), switches and other terminations may fail because they are expected to handle the high peak current continuously - well above their design ratings (especially if a connection is very slightly loose). Remember too that the switch-on surge (inrush current) will be many times higher again - if we assume only 4A (fairly low in reality), the first cycle inrush current could be as high as 320A if all lamps are turned on at once!" " Power Factor CFLs work best if left on for over 15 minutes at a time. Saving electricity by turning off CFLs shortens the life of the lamp. How is that efficient? Answer: It is not. Most CFLs do not work with Dimmer circuits. In fact it can be dangerous to operate standard CFLs on a domestic dimmer, either or both the lamp and dimmer can dangerously overheat! Standard domestic dimmers are a bit of a bodge. They rely on the resistive path of the incandescent lamp to provide a neutral path for the dimmer's electronics. This doesn't exist in a CFL. You will find that even CFLs designed for dimming do not respond perfectly, many will flicker badly when turned down and none will dim smoothly to extinction. They rely on a further bodge in electronics to make them wok at all!
Really awesome blog post. Why do comparisons of bulbs always negate the fact that CFLs have dire colour reproduction? The phosphors used to turn the florescent light source into something broader band only produce a small number of narrow bands of colour. Because the colour of objects is very narrow band by nature, a room lit by a CFL will look very unnatural – many objects will appear darker, or even appear as a completely different colour than they actually are because they can’t reflect the very specific wavelengths of the CFL. This is completely missed by simple lumens calculations and is precisely the reason why they make rooms look dreadful.
ckmapawatt's picture
I use CFL's all over my house and they make the rooms look great. Maybe you are getting poorly manufactured CFLs or earlier models of CFLs. If you haven't tried them lately, give them another shot, just make sure you get the right "color". If you get a "bright white" CFL, then yes, it will make a room look bad. But if you get a "warm" CFL, it will look very close to a regular old incandescent.

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