Here comes the sun, so let's put it to work

April 3, 2009 8:45 AM

Small, inexpensive solar projects for the yard? Got one done and I'm curious about what else I can do...

I'd been wanting a small water feature in my yard for a while. With the layout of our place, though, power is a problem. Last week I got the idea to try solar, since if there's one thing we have plenty of here, it's sunshine. I took an unused solar light, a cheapo tabletop battery operated fountain, and some pots and put a little yard fountain together. And it actually works, which is a small miracle. We love it and now I'm wondering what else I could do out back. (A pic - http://sketchpenguin.com/photos/garden/finished.jpg - the solar light in back powers it. The light itself no longer runs, which is no biggie because you can't really see it at night anyway. During the day it just looks like an idle solar light. It's not running in this pic since the sun is almost down.)

I have 3 more unused solar lights. We got them on clearance for $2 each, so they're not a huge expense. In optimum sun, it generates 3.2 volts. The current reading was hard to figure out as the meter wasn't cooperating, but it looks to be 100 milliamps. For the fountain, it's built to run on two AA batteries, and the pump needs all 3 volts. Any shade and it shuts off. I had to remove the batteries from the solar light since there's not enough juice to charge them and run the pump. (The pump runs about seven hours a day, which will increase as summer comes along.) Given this info, any ideas for fun outdoor projects that can run on this kind of power? And can I get more juice if I wire the solar panels together? Thanks!

posted by azpenguin to home & garden (4 comments total)

You can get more current for sure if you put several solar panels in parallel, and you can get higher voltage by putting them in series.

What about a solar-powered spinning... thing... you know like those plastic yard decorations that spin when the wind blows? Except you could make something that spins when the sun blows instead. ;)
posted by FishBike at 8:50 AM on April 3 [1 favorite has favorites]

You could probably power your doorbell that way. If memory serves, doorbells run off low voltage from a transformer.

And if the scope of this question includes non-electric solar projects, how about a solar cooker?
posted by bricoleur at 9:16 AM on April 3

what about asun jar? less utilitarian, but very pretty at night. i made a few, and they have taken the place of candles on our patio.
posted by bluloo at 9:57 AM on April 3

A shed light like this (ready-made) one might be an interesting project. You could cobble one together quite easily using a battery-powered LED or fluorescent lamp, a simple charging circuit, some NiMH batteries and a few square inches of solar panel. More generally, any project that needs to be less sun-dependent will benefit from modifying it to charge a couple of batteries.
posted by le morte de bea arthur at 11:18 AM on April 3