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Mar. 14th, 2006 @ 09:28 pm Light bulb economics
Current Music: "Mother" by Tori Amos from "Little Earthquake
Let's work this out: I just paid $84.72 for a 12 pack of compact florescent light bulbs for the new chandelier. A 12 pack of incandescent light bulbs from the Home Depot cost $12.74. So you would think I'm $71.98 in the whole.

But, wait. The rated life of the incandescent bulbs is 2000 hours, and the CFLs is 8000 hours. So I'd have to buy 4 sets of incandescents to last as long as the CFLs. So they'll cost $50.96 over the same lifetime. So now the difference is $33.76. (we'll ignore the fact that I'm comparing lots of 12 and will only need 10 for the chandelier--I have to buy them both in cases to get the pricing.)

The most expensive part of this is the electricity. I pay about $0.13/kWh for electricity. A chandelier full of 40 watt incandescent bulbs burns 0.4kW. Over an 8000 hour life that's 3200kWh. At $0.13/kWh that costs me $416 over the life of 4 sets of these bulbs. Over the lifetime of one set of CFL bulbs, which burn 9 watts a piece, or 0.09kW, over 8000 hours, 720kWh, at $0.13/kWh is $93.60.

Total costs of incandescent: $50.96 + $416 = $466.96
Total costs of CFLs: $84.72 + 93.60 = $178.32.

So compact florescent bulbs save nearly $300 over the life of the bulbs. Now, that will probably be 5-10 years, so it's not much per year, but it's real money.
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thow chairs
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Date:March 15th, 2006 04:17 am (UTC)
Did you hear about the guy who wants to get Oprah to give every kid in America a CF bulb? I kid you not.
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Date:March 15th, 2006 04:11 pm (UTC)
What if you spent less upfront for the incandescent, and invested the different? What rate of return would you need to make them more worth it than the CFLs? (not including the hassle factor of investing and buying/changing light bulbs more often)
Date:March 18th, 2006 03:57 pm (UTC)
I have a hard time finding bulbs with a base that is skinny enough to fit in my lamps, have you had that problem?