Building a Solar Chicken House

[James Jarrett]

Hi all,

My wife and I are starting to raise chickens. We want to protect the birds and get the most out of them egg wise, so we are going to put a couple of lights in the 10' x 10' chicken coop we just built and surround the coup and run with electric fencing to protect the birds from coyotes (Yes, we have them in NC too).

I have two solec 90 solar panels, and 6 surplus golf cart batteries that are pretty much near the end of their life, but would be good for this.

Our plan is to use a 12v dc electric fence energizer and 1 or two 12v dc compact flourecent fixtures in the house on a timer.

My question is, I'm trying to do this on a shoestring budget. I already had the panels, and by running everything of direct 12v, I avoid the cost and power loss of an inverter, but I need to come up with an inexpensive charge controler to keep the batteries (I'll proabaly only use two or four of them) from getting over-charged, especially during the summer.

Any suggestions?

Also, what size/grade of blocking diode should I use.
Thanks,

James

[Rob Beckers]

Hi James,

How about a (used) car charge controller? You can find those really, really cheap.

The really old ones are mechanical, almost anything made in the last 20 years will be electronic, they're very rugged. Voltage and current wise it would be a pretty decent fit (depending on how large your batteries are). They cut off at a preset voltage (factory set for flooded lead cells, so that's good too).

Now the disclaimer: I've not actually tried this. Just a thought that seemed like a good one. If you actually try this please let us know how it works out....

-Rob-

[James Jarrett]

Can you point me to an example of what you are talking about? Im not sure I have ever seen an automotive charge controller, I thought those were built into the alternator. That would indeed be perfect if I could find one.

James

[Rob Beckers]

They are in new cars, but not too long ago they were seperate little boxes. I've replaced them on cars and motorbikes. I'm not sure if they have the rectifier built in or not, if so you'd bypass it or take the diodes out altogether. Actually, come to think of it (it's been a few years since I messed with this stuff), the rectifier would be part of the alternator, the charge controller was separate. If you have a car dump nearby just ask them for any brand/type for a 12V system, shouldn't be more than a few bucks for an old one. The electronic type is preferred over the mechanical ones (being mechanical they have a limited life time, that's how I ended up replacing them).

-Rob-

Edit: I knew they weren't called "charge controller" in a car (English is not my native language, what can I say...). So what I mean is the voltage regulator. Basically it'll charge with whatever your panels can provide up to a set voltage, then switch off charging. This isn't exactly the most elegant way to charge batteries, but if they're old or inexpensive and you don't mind adding a bit of water on a regular basis it should get the job done for very little money.

[Chuck Morrison]

James,
I like Rob's idea about using a car voltage regulator, although some of the ones I've seen have a lot more connections than just ground, charging source and battery. I've replaced some tractor regulators that are very simple and don't have connections for computers and such. If it was me I'd go with a simple mechanical one, maybe an old VW bug voltage regulator for example. It should be pretty cheap compared with a Trace C-40.

Just a comment on Coyotes. I listen to them serenade me every evening. Even though folks say they travel alone, they often travel in packs to hunt. I wouldn't trust an electric fence to keep them out. I've seen them jump and crawl under fences.

I have one chicken, who's a wiley old bird having survived a "friendly" attack from the dog a few years back. She roams free during the day and has a fully enclosed cage she retires to every night. The door to the cage is too small for a coyote to get into but it's always open. She's usually up in her perch away from the door. I worry more about hawks and owls than I do coyotes, but any of them could get her. When I lived back east I had problems with skunks and weasels, the weasels being the worst.

Best of luck with the flock.

[James Jarrett]

Thanks for the tip on the voltage regulator, I'll see what I can find.

As to the Coyotes, I know what you mean. We have a "three Tier approach to protecting the flock. First of all there is the electric fence around the whole yard (about an acre) This is the "roaming zone" that we will let the chicks roam in only when we are out and about to keep an eye on them during the day.

Then there is the "chicken run" wich is 10' wide and 50 feet long made of 5 foot high dog wire (2" x 4") and stapled into the ground every foot or so. (or will be when we have all the staples in)

Over the run we have 1" x 1" deer netting to keep small animals, birds and hawks out (it goes all the way to the ground also.

Then there is the chicken house. Only one entrance (when the door is shut) and it is 8' tall with "Oh S**T" perches in the rafters so they can "escape".

It's not perfect, but it's pretty good.

Thanks for the tip.

JJ

[Kurt Treutlein]

Hi James,

How about a (used) car charge controller? You can find those really, really cheap.

-Rob-

I don't see how these could work. Automotive "Voltage regulators" control the alternator, by feeding more or less current into the rotating field coil, depending on the battery voltage they sense. As the battery charges up, it's voltage increases and the "Voltage Regulator" senses this increasing battery voltage and turns down the alternator output to suit. If you turn on the headlights (say) the resultant extra draw on the battery reduces it's voltage and the "Voltage Regulator" increases the alternator output to match.

A charge controller on a PV system senses the battery voltage and reduces the current from the PV panels when the battery voltage reaches full charge. It does this by introducing a resistance into the circuit, thus reducing the current, or even blocking the current flow entirely. It will also usually have a blocking diode in it.

Where do you get one? In Oz, I would go to Dick Smiths, or Jaycar or even Tandy, or any of the alternate energy shops around the place. In the U.S.----- Radioshack perhaps? Many places here in Oz will sell you kits, for under $20 if I remember rightly. Don't get talked into a "you beaut" all singing and dancing device that does everything. All you need is actual charge controlling.

Kurt

[Rob Beckers]

I don't see how these could work. Automotive "Voltage regulators" control the alternator, by feeding more or less current into the rotating field coil, depending on the battery voltage they sense. As the battery charges up, it's voltage increases and the "Voltage Regulator" senses this increasing battery voltage and turns down the alternator output to suit. If you turn on the headlights (say) the resultant extra draw on the battery reduces it's voltage and the "Voltage Regulator" increases the alternator output to match.
Kurt

Hi Kurt,

My voltage regulator experience is from about 20 years ago, while working on cars and motor bikes. What you say rings true with the vague memories I have of them. So, forget about my voltage regulator idea, it was just a thought (would be cheap if it worked)...

-Rob-

[Rob Beckers]

James, did you take a look at the smaller regular solar charge controllers? Their prices aren't too bad. Did you mention you're going to put around 180W of solar over the chicken coop? So that would be around 15A max. The Phocos line of charge controllers (http://store.altenergystore.com/Charge-Controllers/Solar-Charge-Controllers/Pwm-Type-Solar-Charge-Contollers/Phocos-Solar-Charge-Controllers-Pwm/Phocos-CML-15-15A1224V-Charge-Controller/p1014/) is not bad in their pricing, for $45 you have a 15 Amp controller.

Amazon.com has a few cheap charge controllers listed as well. There's a 10 Amp controller for just $26. Except for a few sunny and very cold days that'll still get most out of your panels.

-Rob-

[James Jarrett]

Thanks,

Yes, I have looked at some of the cheaper Charge controllers. I was about to tell you that 15 amps was not enough. My memory (worthless thing that it is) said that these were 7 amp panels, but I wanted to be sure so I looked them up.

They are rated at 5.2 amps short circuit, and 4.86 amps max charge current.

So a 10 amp charge controller would PROBABLY be good enough, a 15 or better would definately do it.

I'll have to go back to ebay et.al and see what is there.

So much for trusting my memory.

James