Friday, September 18, 2015

Simple PV Solar System

A PV Solar System is one of the most comforting and affordable things a Survivalist/Prepper can have. Just the thought of knowing you have electric power for lighting and communications for years while others are in total darkness is priceless!

A quick history note:
I have been using my PV Solar System for 7½ years non-stop 24/7 and the system works perfectly with almost no attention what so ever. About 1½ years ago I upgraded my panels from the Harbor Freight three, 15-watt panels to, two 100 watt panels, a 1000 watt inverter and two 12v RV/Marine batteries. The purpose was to be able to run a small refrigerator during a grid down situation along with lighting and communication needs.
However, a couple weeks ago we had a very close lightning strike and it caused my controller to fail and subsequently over charged my batteries and destroyed them also. So I have to basically start over except for the PV Panels.

Right now this is my current, low cost, 200-watt system:
It has one 12v deep cycle marine battery, a 30 amp charge controller, two 100 watt solar panels and a 1000 watt inverter. I know that doesn’t sound like a lot of watts, but this system guarantees I will have endless amounts of needed electricity during a grid down event especially when there’s no gas available for the generator.

What do I power with this system?
It provides more than enough electricity to run my kitchen 23 watt flat panel TV, my garage radio, my chargers for “AA” batteries and recharging all my communication radios that have internal battery packs and charge the batteries for all the LED lights I have so at night I’m not living in the dark. 
If I had a couple more batteries and solar panels along with full sun all day at my location I would easily be able to power my 5 cu ft chest style refrigerator that uses 640 watts every 24 hours. How great would that be, cold beer and safe fresh food storage while others are in the dark.


Here’s what my inexpensive system looks like.

The heart of the system:
In the upper right corner is the charge controller, lower left corner the battery, lower center the inverter and upper center a state of charge chart.

On the roof are the two 100 watt PV Panels:
The dish has nothing to do with the system this was just the only place on the roof where because of trees it has a clear alignment to the satellite. The panels have to be there also because this is the only place where they can get 3-4 hours of sun a day. The rest of the day the roof and panels are shaded by trees. Here the panels are just entering the full sun cycle for the next 3 hours then they will be in tree shade the rest of the day.

The 12 volt RV/Marine Deep Cycle Battery:

Battery specs.

The controller:
It shows the state of charge, battery volts or the array voltage coming into the controller.

The Inverter:
1000 watt continuous with a 2000 watt surge capability.  It easily handles a 5 cu ft refrigerator or freezer.

Important Information Sources:
Please pay close attention to the wire/cable sizes used in your system. Too small a gauge can overheat and burn your house down.
Probably the best source of small PV system wire size information is at this link: https://handybobsolar.wordpress.com/ and a retailer is http://www.backwoodssolar.com/


Bottom Line:
It doesn’t get much simpler than this. It’s hard to find a reason not to have a small system even if just 100 watts for emergencies. This system is also a very good educational tool for your family and your neighborhood kids.

Cost of this system:
$260 - 2-100-watt panels (Home Depot)(for a starter system just one panel is fine)
$81 – Battery (Walmart)
$39 - Charge Controller (Amazon)
$45 – Inverter (Harbor Freight)
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$425 – Total Cost (or $295 with one PV panel)

And before someone tells me that I’ll never see a payback from this system! This system is not about payback or economy or free electricity, it’s about personal security and a supply of electrical convenience in terrible times. Can’t put a value on that!


10 comments:

  1. I been running my life on solar for 15 of the past 25 years. I am somewhat of an expert on the subject. One battery will not run a refrigerator over night. Even the smallest ones draw way more power than that deep cycle battery will provide. www.sunelec.com has solar panels from as low as 29 cents a watt. Home depot is a rip off on the price of panels Batteries are going to be your most expensive part of your system. I run a bank of 12, 1100AH 2 volt cells for a system voltage of 24 volts. I applaud your article and hope you continue to provide more information for the people that want to outlast the great event.

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    1. Thanks for your experienced comment.
      You are correct one battery will not run a 5cu ft frig 24 hours. My frig (a converted chest freezer) consumes 640 watts (measured) over 24 hours. So as I stated the system would have to grow slightly to maintain the frig. My system is not a whole house system but an emergency system to provide a few basic needs.
      Home depot pricing isn’t totally unreasonable when you consider free shipping and should anything go wrong with any component they take it back or refund your money no questions asked. Unlike the mail order companies where service can be an issue and shipping you pay for.

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  2. Awesome, The pictures helped a lot. I love it

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  3. Thanks Cheryl, I try to have a lot of pictures as it helps explain what I'm doing and you know, a picture is worth a thousand words!
    Do you know if you put your cursor on the picture it will open them up full size?

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  4. Thanks for the write up !! I will be doing this ASAP!

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  5. This comment has been removed by a blog administrator.

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  6. Hello mike, it might be good idea to stress the importance of proper cable sizing to those who are new an try to replicate your system...just thinking.

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    1. I had thought about that but every system is different and therefore could be dangerous litigation wise for me. Improper sized wire can overheat, start on fire and possibly burn your house down. Different wattage PV panels, different amperage controllers, different wattage inverters and different distances the current must flow. The new user needs to do research and also speak with solar providers for guidance about the wire sizes and fuses that will match his/her system.

      As a general rule whenever possible, use larger diameter wire then what is calculated. This simple and inexpensive improvement can yield 5% to 20% more power from your PV panels/system.

      Probably the best source of small PV system information is at this link: https://handybobsolar.wordpress.com/ and a retailer is http://www.backwoodssolar.com/

      For those who simply must know what I used in this 12 volt system:
      I used #6 wire from the PV panels to the controller with a 20 amp fuse (the panels to the controller is a short 8 ft. distance). #6 wire from the controller to the battery. From the battery to the inverter #2 wire with a 70 amp fuse. All wire is stranded and all terminations are crimped.

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  7. Great post Mike, this makes it understandable for even me. And your last paragraph is spot on. Everything in the world is not about money. Not in my book anyway.

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Your thoughts are welcome!