Do you think that the overwhelming base-cost of "green" inventions keeps people from buying them?

I'll reference, for example, the most recent issue of Popular Science (September 2010) and the article they have about new super-efficient LED lightbulbs:

(They do not have the current article online, but here's a brief abstract.)

I'll quote for one of the light bulbs:

"LED bulbs that exactly mimic the popular soft-white, 60-watt incandescent could cost $60. This 770-lumen one has slightly less-warm and less-omnidirectional light, but it costs about half as much.

*Lighting Science Group Definity 9W LED A19 (60W equivalent) About $30 (avail. fall);*"

(This is the top light bulb in the picture.)

HOLY COW! $30 for a single light bulb?!?!?!? That's outrageous, since I can buy an incandescent for $0.56!

So why would I ever buy LED??

Well, I did the math. A new LED bulb can last for 25,000 hours. That's almost 3 years non-stop. A typical incandescent can last for 1000 hours, just over a month and a third. What more, this LED runs on 9W of power, while incandescents are typically equal in consumption and light wattage, i.e. a 60W uses 60W.

The average cost of electricity in the US is about 10 cents ($0.10) per kWh:

So, that means the cost of running an LED bulb for its lifespan and the cost of running an incandescent for a comparable amount of time:

LED: ($0.10 / 3,600,000 J) * (9 J / 1 s) * (9.0e7 s) = $22.5

Incandescent: ($0.10 / 3,600,000 J) * (60 J / 1 s) * (9.0e7 s) = $150

Taking costs of the bulbs into account, and how we need to buy 25 incandescents:

$22.50 + $30.00 = $52.50 (LED)

$150.00 + 25($0.56) = $164.00 (Inc.)

Now we see the true numbers. By buying one of these LED bulbs you can save over 100 dollars, or 68% of the money you would have spent on incandescents. However, do people really do the math? Do you think the initial price of $30 per bulb scares away most consumers, and do you think similar situations exist with other green technology?


As a side note, for people who want to know how long it takes for the savings form the LED to pay for itself:

($30.00) / [(51 J / 1 s) * ($0.10 / 3,600,000 J)] * (1 day / 86400 s) = 245 days (23.5% of its total lifetime).

This is assuming continuous running, so let's say a lightbulb stays on for 6 hours in a day, it will take about 2.6 years to pay for itself. This may seem like a long time, but considering how you will live in a house for several years and can always bring light bulbs with you if you move, it's very worth it in the long run. If we still assume you have a lightbulb on for a quarter of a day, you don't have to replace it for 11.4 years.

Update 2:

*...savings from the LED...

Update 3:

First Grade Rocks:

Just to respond to a couple things you said:

- I thought my link to the DoE showed electricity costs sufficiently; perhaps you put a different meaning to "present value analysis" than what I'm interpreting? I can at least say that in Michigan, where I live, electricity per kWh averaged out in 2010 so far is 9.97¢, which is essentially 10¢. The average for the US so far is 9.93¢.

- You have a good point with moving, but can one not bring lightbulbs when he or she moves?

(On a side note, it's not like the housing market is doing great anyways.)

Also, since LED are solid state devices, they experience little wear and tear, depending on heat and current density. The newer models are built to facilitate cooling, but they are still high-power and thus might be damaged faster because of that. I am not sure what the lumen v. time charts would look like for these particular bulbs, nor what testing results are in regards to environmental problems; good concerns.

Update 5:

First Grade Rocks:

Thank you for that analysis, very detailed.

11 Answers

  • 10 years ago
    Favorite Answer

    Couple of notes:

    1. You really need to do a present value analysis of the electricity cost. You also need to consider how often the light is on and determine projected lifetime and bring that cost to present value compared with the old edisons. (although LEDs would still win, but not by as much).

    2. I haven't experiment with LEDs as a prime source of lighting. (Although, I have been following their progress for years and have some small ones that have work just great). But I know that CFLs never lived up to their claim of longevity. I put two in the bath two years ago and both blew out. I went through several in the garage. In the first case, I think the humidity fried the circuits and in the second, I think the vibrations fried them. Would a LED be able to handle harsh conditions? If not, they may not be a great value.

    3. If someone is planning to move in the near future, they are not as good of a value.

    4. My electric bill last month was $28 -- most of which went to feed the refrigerator. I use a power strip for both my computer and my TV. I only use lights as needed, and most of those lights are CFLs. LEDs are not going to save me much over the short term. Wait 'til a light goes out, then replace.


    LittleRobberGirl -- If your "old" CFL is black or dark near the base, it may need to be replaced. The luminosity of CFLs goes down with use. And if you see that dark band near the base, it is not putting out enough lums per watt to make it worth keeping.


    First, my comment on lums was related to old CFLs not LEDs. LEDs generally have a pretty good reputation for maintaining their lums.

    Also, the failure mode for a LED is not necessarily the LED itself, but more likely the fixture, i.e., everything that supports the LED. See:

    Engineering Economics 101:


    60 W bulb life 1000 hours

    Cost $1.00

    (Even if the bulbs only cost $0.56 the annoyance cost of having to change a bulb is at least worth $0.44!)

    LED 10W fixture service life 10,000 hours use or 10 years service

    (I'm being conservative)

    Cost $30

    Average yearly use 1000 hours (2.74 hours/day reasonable household use)

    Discount Rate: 5% (this is low, but so is the economy; normally you use a higher rate) to get present value.

    The calculation to reach present value for a 10 year stream of constant costs is the one year cost x (1 - .95^10)/(1-.95)

    Edison bulb cost

    Bulbs = $1 * (1 - .95^10)/(1-.95) = $8.03

    Electricity = $.10/kWhr * 60W * 1000 hr/year * (1 - .95^10)/(1-.95) = $48.15

    Present value total costs: $56.17


    Bulb = $30

    Electricity $0.10 /kwhr * 10 W * 1000 hr/year * (1 - .95^10)/(1-.95) = $8.03

    Total = $38.03

    The difference is not that great. If you have a high use area >5hrs/day. Change now.

    Most other household uses, you would probably be best off waiting 2-3 years until the price is down to $10 per LED.

    [And, yes I know, you can play around with lifetime, discount rate, future cost of electricity, etcetera. But I decided to take standard, simple and conservative assumptions.

    As an aside, I want to be an early adopter. I wanted to get an LED yellow post light for the front walkway last year, but all I could find were CFLs. Next time I have an appropriate application, I'll look again.]

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  • 10 years ago

    A lot of people are narrow minded and only see the upfront cost of something, while some (particularly those that are trying to live green currently) are able to look past the upfront cost and see the ongoing cost included. While a 60 dollar LED bulb may seem expensive, it's not that bad when you consider, a person wouldn't need to replace it very often at all, plus their electricity bill would be lower than if they used a conventional incandescent.

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  • lc001
    Lv 4
    10 years ago

    Yes, it is. Most people go green to save money, which means they are in a mode where they feel they do not have sufficient cash to begin with (even if they do). Therefore they are not only trying to economize over the long run, they are trying to go lean at the get-go.

    This puts the green movement at a disadvantage before we even start.

    But then again, tell me who would easily plop a chunk of change on big ticket things like repairs or replacements, green or not? Do we replace working, but old vacuums just because the newer models are more powerful or clean better? If things are in working order, we're not too apt to spend money, no matter how much better the new stuff is.

    Here we will need to rely on acts of God or the Govt to change our collective thinking. But change it needs to be. Rebates seem to have some impact as consumers start to educate themselves on these issues due to costs.

    Good luck!

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  • 3 years ago

    Go Green Inventions

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  • 10 years ago

    Absolutely, I myself waiting for the cost of adding solar energy to my home, there are several ways to do it. GreenDIY has a way, but all of the "KITS" I have seen needs to be more simplified, and we need to work together so that everyone can afford to put it in there homes. Those light bulbs, i would like to have them in my home, but the cost is outrageous. Your electric bill, especially during heat waves, through the roof, we need to make things more affordable, then people are more willing to go green. Personally i am sick of the price of electric, what planet is the electric companies from? Very Good Open Question.

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  • 10 years ago

    Have you noticed you always have to pay extra for something that has the "green" label on it? I'm still looking for something that is green and that actually costs less, and I don't mean investment-wise, I mean right there in the sticker price.

    That might make a difference for the environment, more than a whole bunch of calculations. But while you have those guilty feelings about plastics staying in Nature for 300 years, the research to make all consumer plastics biodegradable at competitive cost is not happening, or you'll be charged more for them.

    I dunno. I'm just sayin'.

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  • 10 years ago

    Thanks for sharing this!

    It provides a good example of a situation in which government incentives and regulation can increase profitability of a free market. A municipality that subsidizes the cost of LED bulbs for a period of time to help people get used them, and to increase their market share, prevents waste and saves money for the community.

    Current federal and state subsidies for fossil fuel have the opposite effect. They prevent cheaper clean energy technology from developing.

    June 8, 2010 7:56 AM PDT

    IEA: To promote efficiency, cut fossil fuel subsidies

    "The International Energy Agency on Monday published an analysis that found subsidies for fossil fuels are higher than previously thought. Cutting subsidies would encourage energy efficiency and low-carbon fuels, it said.

    The amount of money paid to subsidize fossil fuels around the world was $557 billion in 2008, which is up from $342 billion in the previous year. The key findings on fossil fuel subsidies were published in advance of the IEA's annual World Energy Outlook report, which is due in November.

    The IEA, which gathers energy industry data, recommended that governments set up programs to phase out fossil fuel subsidies, which would create incentives to use energy more efficiently and use fuels that emit fewer greenhouse gases."

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  • Karen
    Lv 4
    4 years ago

    The Orifice involved, is an exit, not an entrance, and I fear no good can come of it. Musical farts (or Moby's) can be performed without any prosthetic addition, with dedication and training, and diet can influence the bouquet to some extent. I can't see it catching on. Nice Idea though, and I wish you nothing but good luck with it. edit; Hi Freckles, I can see your lettuce from down here!

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  • Anonymous
    10 years ago

    yes. not many people stop to do the maths ( nice breakdown ta, bookmarked) before they buy. also, many people really cant afford to pay the bulk of the cost up - front.

    if you wanted to be more accurate, you would have to adjust for inflation.

    paul, yes, but here too they are horrendously, eye-wateringly expensive. i remember getting one of the first cfl's at a shocking tenner for one bulb, but, though not normally an early adpopter i just had to, and it did work out cheaper. i'm sick of it now, it just wont die, and the modern ones ar loads better.

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  • 10 years ago

    Yes. People notice upfront costs, or even upfront inconveniences, but are unaware of slow drains on resources.

    that's why most people don't even bother to optimise their car tyre pressures.

    Edit: does ayone know if you can get LED bulbs in the UK, and does anyone have experience with them?

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