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sammy
11-29-2011, 2:36 PM
Ok, so I have decided on getting this solar system from Costco, http://www.costco.com/Browse/Product.aspx?Prodid=11671549&search=solar&Mo=22&cm_re=1_en-_-Top_Left_Nav-_-Top_search&lang=en-US&Nr=P_CatalogName:BC&Sp=S&N=5000043&whse=BC&Dx=mode+matchallpartial&Ntk=Text_Search&Dr=P_CatalogName:BC&Ne=4000000&D=solar&Ntt=solar&No=8&Ntx=mode+matchallpartial&Nty=1&topnav=&s=1

260 watt 12 volt. Now I need to decide what kind of battery or batteries I should get. I am hoping to run a small 500 watt refrigerator, charge flashlight and laptop batteries.

I am starting from zero here. I know that I need deep cycle but what kind? The longer they last the better. HELP Sammy

glockman19
11-29-2011, 2:52 PM
Most rooftop panels today are in the 200 watt catagory...here is a link to the most efficient pannels available...
http://sroeco.com/solar/most-efficient-solar-panels
And...
How do you expect to run 500W off a 200W panel?

You want at least 3 of these...
http://www.gogreensolar.com/products/sanyo-hit-n220a01-220-watt-solar-panel
Have an electrician professionally install the system including inverter, controller and battery backup. It will cost little more to get what you need.

sammy
11-29-2011, 2:57 PM
My thinking is the solar panel just charges the batteries. These batteries are capable of drawing 500 watts easy for short periods.

glockman19
11-29-2011, 3:21 PM
My thinking is the solar panel just charges the batteries. These batteries are capable of drawing 500 watts easy for short periods.

Talk to an electrician. Do it correctly.

Dutch3
11-29-2011, 3:22 PM
My thinking is the solar panel just charges the batteries. These batteries are capable of drawing 500 watts easy for short periods.

That's only a 200W inverter (which is probably a "peak" rating). It's not going to run that refrigerator. If you are lucky, it may only blow the fuses when the fridge tries to start instead of melting.

The best choice for batteries would be something similar to a 6 volt golf cart battery (Trojan T-105, etc.) Wire a couple in series for 12V output. Remember that regardless of your battery capacity, AC output is going to be limited by the inverter capacity.

sammy
11-29-2011, 3:24 PM
That's only a 200W inverter (which is probably a "peak" rating). It's not going to run that refrigerator. If you are lucky, it may only blow the fuses when the fridge tries to start instead of melting.

Crap, you are both right.

Any recommendations on an electrician?

cranemech
11-29-2011, 3:56 PM
$1000 seems pricey for that system from Costco.

thenodnarb
11-29-2011, 4:03 PM
I think you have the right idea. Use the solar panels to charge the battery bank. Run a 1000W inverter off the battery bank, and run the fridge for an hour or so to get it cool.

Or you could buy a gas fridge as a backup. I bought one from an RV used for 50 bucks. I can run it with propane, or failing that, a big candle or sterno. All it needs to do is heat a certain spot and the heat from the candle runs the cycle. It can be plugged in most of the time to 110v so its already cool and when the power goes out, switch over to propane. It might even switch over automatically. I would put it in the garage because I don't trust ammonia fridges inside the home. If it leaks, you're dead.

You could also just use your car as a way to charge batteries or run lights for short periods of time. Its kind of a waste of fuel, but it depends on your purpose. Is this supposed to be for SHTF? power outages?

BTW, what is the energy rating for that fridge. I know mine only uses 1 KW per day(assuming you aren't getting into it all the time). Thats 1000 watts in a 24 hour cycle. The key here is how much wattage/amps does is use when it is cycling? Your 260W setup should produce enough electricity in an 8 hour cycle to run an energy efficient fridge, and maybe some lights too. When buffered by the battery bank, I think you'd be fine. You're not going to "fry" the fridge if it doesn't get enough power. if anything, its the charge system that pops a breaker.

You'd probably be fine with two deep cycle 12v batteries hooked in parallel. Make sure to get a charge controller that is designed for solar. Deep cycle batteries like to be discharged fully before they are charged again.

All that said, a generator is a much better solution, and you can still do the battery bank/charge controller/inverter to make the most of the energy produced.

Dutch3
11-29-2011, 5:27 PM
All that said, a generator is a much better solution, and you can still do the battery bank/charge controller/inverter to make the most of the energy produced.

I use both. About 120W of PV to charge a deep-cycle battery and a 700W inverter to provide lights and charge phones and laptops without running the generator (noise, fuel consumption).

The generator is there to do the heavy lifting (fridge, freezer, well pump) but I only run it for a few hours at a time. It will charge batteries as well on days with little/no sunlight.

Fern
11-29-2011, 5:45 PM
http://www.wholesalebatteriesdirect.com/52272-12-v-200-ah-4d-deep-cycle-agm-solar-battery-ub-4d-also-replaces-210-ah.html

Price per Amp Hours are similair between brands.

http://compare.ebay.com/like/290617135292?_lwgsi=y&ltyp=AllFixedPriceItemTypes&var=sbar

clbshooter
11-29-2011, 5:48 PM
Checkout backwoods solar. I have gotten their catalog before. They have complete systems for sale in a kit form and may be able to recommend a local electrician. Google them but I like their catalog just to compare the different size systems. They have been doing off grid for a long time. Good luck

Bend
11-29-2011, 6:48 PM
See:

http://www.ar15.com/forums/t_10_17/652336_I_built_a_mobile_battery_bank_and_inverter_ combo__what_do_you_think___Pictures_.html&page=1

thenodnarb
11-29-2011, 7:04 PM
See:

http://www.ar15.com/forums/t_10_17/652336_I_built_a_mobile_battery_bank_and_inverter_ combo__what_do_you_think___Pictures_.html&page=1

thats pretty cool right there!

wheels
11-29-2011, 7:38 PM
Start with what devices you want to run - and how long you want to be able to run them (6, 8, 12, 24). This gives you the size of the battery bank you need to run your devices.

Now you know how many batteries you need - how many panels will it take to fully charge the batteries - during the 6 - 8 hours you will get on a good day (depending on where you are)? Figure a bad day maybe 1-3 hours of sun.

dave1947
11-29-2011, 7:46 PM
DO NOT discharge deep cycle batteries completely before rechage,, take down to 50% only before recharge and 6 volt golf cart batteries are in series to get 12 volts,not parallel

http://www.marine-electronics.net/techarticle/battery_faq/b_faq.htm

xgi1991
11-29-2011, 8:15 PM
Ok, so I have decided on getting this solar system from Costco, http://www.costco.com/Browse/Product.aspx?Prodid=11671549&search=solar&Mo=22&cm_re=1_en-_-Top_Left_Nav-_-Top_search&lang=en-US&Nr=P_CatalogName:BC&Sp=S&N=5000043&whse=BC&Dx=mode+matchallpartial&Ntk=Text_Search&Dr=P_CatalogName:BC&Ne=4000000&D=solar&Ntt=solar&No=8&Ntx=mode+matchallpartial&Nty=1&topnav=&s=1

260 watt 12 volt. Now I need to decide what kind of battery or batteries I should get. I am hoping to run a small 500 watt refrigerator, charge flashlight and laptop batteries.

I am starting from zero here. I know that I need deep cycle but what kind? The longer they last the better. HELP Sammy

Itís not a bad starter system Sammy, it will get you going. Replace the inverter with a larger one and get yourself a few 100 amp hours of deep cycle batteries. I use wallyworld (walmart) deep cycles on mine, cheap to get in to and easy to service. Donít worry about getting a installer, do it yourself, you are a prepper after all. The web is a wealth of information and it is not rocket science, be more than happy to help you out just pm me. The thing is, you can always grow the system once you have the basics, get into it, learn, and adapt. Youíll have a lot of fun doing it.

Ironmany2k
12-01-2011, 12:39 PM
Agreed! and then add a 5 Amp battery charger/maintainer to it. It will keep the batteries topped of when the sun goes down and the panels will keep it charged during the daylight. If you loose power the batteries will keep it running. I use a similar system to run my ham radio station.

Keep the fridge plugged into the inverter all the time. Keep the inverted connected to the batteries. Keep the batteries connected to the charger/maintainer and the charge controller.

http://www.batterystuff.com/battery-chargers/12-volt/marine-chargers/PT12v022-0157.html



Itís not a bad starter system Sammy, it will get you going. Replace the inverter with a larger one and get yourself a few 100 amp hours of deep cycle batteries. I use wallyworld (walmart) deep cycles on mine, cheap to get in to and easy to service. Donít worry about getting a installer, do it yourself, you are a prepper after all. The web is a wealth of information and it is not rocket science, be more than happy to help you out just pm me. The thing is, you can always grow the system once you have the basics, get into it, learn, and adapt. Youíll have a lot of fun doing it.

off grid
02-24-2012, 7:22 PM
Hello
Just ran across your post. If you still need any help with this let me knw as solar is what I do for a living, and would be happy to give some guidence if needed.
Mike

Darklyte27
02-25-2012, 5:55 AM
Wow, old thread, Sammy wish you talked to me about this since we live so close to each other. I have a small off grid setup.

also check out this guy and look for the solar near bottom right of the page

http://www.2manytoyz.com/

I have 2 135 watt 12 volt panels at 310$

the newer models are now 140 watts for about 330$

140 watts is the highest you can get at 12 volts.

I have a morning star 12/24 30 amp charge controller http://www.solar-electric.com/ps-30m.html

my 1000 watt inverter http://www.solar-electric.com/sa10wa12vosi.html

my two 12 volt 104 amp hour batteries http://www.tristatebattery.com/product_info.php?cPath=191_371&products_id=1121
http://www.solar-electric.com/pvx-1295.html

Ive ran my 8.4 amp shop vac on my inverter for about 15 mins and noticed the fan on the inverter go on.
Ive used the inverter to run multiple batter chargers with no problem or fan going on.