Solar Lights

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solar lights
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Solar Lights

Post by solar lights »

I'm figuring out whether solar powered lights really help reduce electric bills... Do any of you guys have any information on this?... thanks!
shawn
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Location: Cambridge, Mass.

re:solar lights

Post by shawn »

Let's think straightforwardly about this, and inclusively.
If you pay for solar power on your bill (not likely), then use that to power your lights, then you pay for your lights to be solar powered.
If you are setting up a custom, off-grid solar powered lighting system, besides the simple lights you can buy at a hardware store, the answer is too complicated, but it probably will reduce your utility bill.
The following two scenarios are more likely.
If you buy solar lights not to replace anything that's producing light using electricity from your utility, then you're not reducing your bill.
If you buy solar lights to replace lights that run on your utility's power, then you are reducing your bill. Let's examine the cost/benefit analysis: Suppose you pay $25 for 5 solar path lights, replacing 5 25W lights that once lit your path. At $0.10 per kWh (rough rounding not including fixed costs on your bill that aren't dependent on how much you use), $25 buys you 250 kWh. That's enough energy to run 5x25W (125W) for 2000 hours. At 10 hours a night, that's 200 nights. So, the solar path lights will reduce your bill enough so that they will pay for themselves in 200 nights, or under a year. You could say that replacing 5 25W lamps that run 10 hours a day with lamps that don't use billed electricity will reduce your bill by about $40 a year.
I live in a place where I don't need air conditioners. The biggest portion of my electric bill is for my refrigerator, then the dehumidifier, then my computer, then the lights, then all the other little things, stereo equipment coming in as the least. My heating, cooking, and hot water are all done by natural gas, costing me much more than my electric bill.
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