Help me build a basic solar charging system
 

During the hurricane, we lost power for 5 days total. We ran a generator most of this time. If this was a real emergency, the use of the generator would be only to pump the water from the well and to empty the septic tanks.

So now I have a problem.. how to power the septic aerator and basic (and I mean BASIC) lights and a fan during those times that the genset is not running.

Here is my thoughts so far:

4 to 6 golf cart batteries
1 1000 watt inverter (RV grade or better)
1 solar charge controller
1 standard 120v charge controller (could be built into inverter)
250 watts of poly or mono crystal solar panel (or somewhere close).

This should allow charging during the few hours a day the genset would be running, while still allowing use of CF lights, a small fan and the septic aerator.

Thoughts, suggestions on products?




When the genset is running, fee

Re: Help me build a basic solar charging system
 

I don't know if they are selling this product yet but:

http://www.nanosolar.com/

Check out the nanosolar solarply panels. They are next-gen solar panels that are supposed to be cheaper than current tech.

Re: Help me build a basic solar charging system
 

my only thoughts are go with dedicated deep cycle batteries rather than
golf cart they cost only a little more per AH and you should get quite a few
more years of service out of them.

double or triple the inverter size you will be surprised when that will come in handy ie motor starting of certain tools and appliances.

i dont use a charge controller for my solar setup because i have a
small solar array for a comparitively large storage capacity.

ie my solar charging capacity in amps is only about 1% of the total
storage capacity of the bank in amphours.

i think you can safely go out to 5% but dont quote me on that?

also have an overvolt alarm just in case.

Re: Help me build a basic solar charging system
 

good advice from damoc.
Look in the yellow pages.
Call and talk to battery distributors
look into a set of L16 batteries. 6 volt, 400 amphour rating, use them in series pairs for 12 volt nominal system, or in strings of 4 for a 24 volt system.
Charge controller is pretty inexpensive, around a hundred bucks for a 20 amp device

Re: Help me build a basic solar charging system
 

Go to Homepower.com , lot's of info. As I've stated on on other threads home power has been an invaluable source for info , and equipment ratings.

Re: Help me build a basic solar charging system
 

also, the six volt battery array may provide some cost efficiency when weeding out bad cells. they do go bad unevenly for various reasons

Re: Help me build a basic solar charging system
 

if you want something quick and cheap
if you have an old junker sitting around with the electrical system intact
buy one of those solar trickle chargers that sits on your car dashboard and charges your battery
and there's convertors that will convert the 12 volt to 120
and if you need more power, add more batteries to the original
this setup has it's limits, but it's a nice quiet secluded source of power/electricity

i have a setup like this waiting for me at my auto junkyard bug-out out in the county


http://www.electronics123.co.nz/osc/images/1381.JPG http://www.powersuppliesonline.co.uk...10/TPS-946.jpg

Re: Help me build a basic solar charging system
 

C-g: Those panels you have pictured above are only for very small trickle charging....just barely above the amount to keep a battery from self discharge and keep up with a few light draws like a car clock. If you actually draw any from a battery, one or even two of them won't keep up. Running the car radio, for example, an hour would take all day charging by one of those panels to replace what the radio drew from the battery.

Tech Guy:

What you have listed will get you a decent start, as long as you realize you will have to monitor the batteries closely and fire up the generator once or twice a day.

Actually, a battery bank is the smartest way to use a generator.....use the generator to fill the bank, then draw slowly from it, rather than running a generator for just a small load. The panels, in your case, would merely be a supplement to the generator running. You will need that charge controller between the generator and the batteries.....make sure it can plug into your normal house current so you can keep the bank charged up during normal times as well.

I'd also agree with Fullpower......look at a bigger battery bank.....in fact, I'd look at that BEFORE even adding any solar panels, honestly, since you plan to use this more as a 'generator extender" rather than a true solar system ( which would require a LOT more panels ). I just bought a set of eight 8L16 deep cycle batteries for 200 bucks each from a local Deka dealer....these are the TALL version of the L16 series, and rated at 420amp/hr 6v.

The 250 watts of panels are probably going to run you in the 1200 buck range, spend it on more batteries instead. Assume you get 6 hours/day out of your panels....that's only 1500 watts over that 6 hours....or 1.5kwhr.....your generator ( assuming it's a 4 or 5KW or so ) would do that in 20 minutes of extra running in a day...so the question becomes "how much does 20 extra minutes of fuel cost versus the cost of 250watts of solar panel"......and I think you'll find the generator you're gonna have to run anyway wins that deal.

Note this is the situation ONLY for a emergency power deal. NOW if you plan those batteries ALL the time as part of your house use, then using solar to fill the batteries starts to make a whole lot more sense.....you're still gonna have to increase panels or be pretty stingy on your power use, and probably supplement with generator, but that is a case where panels would make more sense.


SO, I go

1. Generator ( which I take it you have )

2. Batteries.....size them enough to run everything except maybe the well pump for at least 12hrs.

3. Generator to battery charger/controller

4. Inverter ( I'd also up the size of that )

5. Solar add on

You might also look at getting some 12v items ( truck stops are great for this ) such as that fan, coffee pot, etc, and use DC directly where ever you can to save on a larger inverter and the power loss you get thru an inverter.

Re: Help me build a basic solar charging system
 

My wife and I are cruising sailors - and you might be able to benefit from the cruising community's knowledge.

Sun Electronics in Miami, FL has the ABSOLUTE best prices on solar modules and all things solar/battery/charging equipment.

Sometimes they'll have 2nd's in stock that are only visibly blemished but still work perfectly and still carry the 25 year warranty.

They let you test them right in the store - they have a huge wall of bright lights and a voltmeter - pretty nice folks.

You can most likely have them ship to you and the shipping would be less than the taxes you may pay elsewhere.

Check it out - http://www.sunelec.com/

Good luck,

M.

Re: Help me build a basic solar charging system
 

They aren't selling it. If they did it would revolutionize the way people power their homes. At 1$/watt it is very competitive with grid based power. In places like Hawaii, Texas, and California you would see massive demand for those panels.

Even another company, first solar, isn't selling their thin film panels to the public. Instead they are selling them to companies that build large scale solar projects.

Re: Help me build a basic solar charging system
 

Well, that sucks. Thanks for informing me.

Re: Help me build a basic solar charging system
 

I wonder how much one would have to buy in order to get them? While not applicable to TechGuy's issues, it might be a good investment for a retreater community. :shine:

Re: Help me build a basic solar charging system
 

Dont feel too bad about it...NanoSolar's product is CIGS and as types of panels go, they're relatively inefficient. What you would save in cost, you'd lose in having to buy more. The product really isnt all that much different, just the means they use to make it (printing the chemicals). The crystalline panels out there market now represents the foreseeable future - at least in terms of whats really practical.

The next step, imho, is enhancing solar collection....lots of tracker mechanisms out there and solar concentrators are fairly simple to make with a series of simple flexible plastic fresnal sheets.

Anyways, the pv tech is where its going to be for awhile...just a matter of putting it all together.

Re: Help me build a basic solar charging system
 

http://www.northerntool.com/webapp/w...atchallpartial

:shine:

Re: Help me build a basic solar charging system
 

What is the power draw of the septic?