Do you think that the overwhelming base-cost of "green" inventions keeps people from buying them?
(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); lsgc.com*"
(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?
($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.
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.
Thank you for that analysis, very detailed.