Off Grid
Off Grid

I live in central Florida near the coast where we get plenty of sunshine. After completing my Aquaponics system I wanted to have a backup for when the power goes out. So I figured that solar power is a good way to go here. We have been lucky for the past six years with no major hurricanes but that is unusual.

We have been without power for seven days, five days, three days and so on. Most times it is at least one day so I designed for three days without power. A lot of the following information can apply to wind power as well.  Let me say that working with solar panels and batteries can be dangerous. I have a background in electronics and have certifications from two tech schools and a solar design and installation certification.

I think that it is worth it to at least get a certification in solar installation so you know the basics. If you are unable to do that then please do a thorough study on the subject.  We need to have a great deal of respect for electricity and the dangers of batteries. Let me explain the basics. After getting a certification in solar design and installation I decided to do a small experimental system. I found a small photovoltaic (PV) system on Amazon made by Sunforce.

Off Grid
Off Grid and Solar Powered

I added another kit from Harbor Freight I just used the panels from the second kit because I didn’t care for their charge controller. It would drain the battery at night.  Before buying anything make sure that you have enough sun in the location of your installation. Six hours of sun without interference from trees or anything that will block the sun from reaching the cells. This is known as “Shading” In my location the panels are oriented to the south.  While I am talking about orientation, it makes sense to mention Azimuth here. The Azimuth is the angle at which the panel is aimed at the sun for maximum power.

Watch the sun at different times of the day to see how it tracks across the sky.  In general PV solar panels should be mounted at an angle of 10 to 15 degrees plus the site’s latitude. http://itouchmap.com/latlong.html Where there is severe weather think about how you will protect your panels because they are prone to breaking and once the glass is cracked and the cell is exposed to oxygen it will become useless.

The Installation:

off grid
off grid

Have enough tarps or blankets to cover the panels from the sun. You don’t want power running down the wires until everything is connected. You can orient the panels after they are wired up but do get them close to where they should be. The charge controller and battery should be close enough to your fish tank so that you can power the bilge pump.  The wires from the solar panel output will connect to the charge controller input. The wires from the charge controller’s output will connect to the deep cycle battery.

The bilge pump will also connect to the battery. That is all that there is to a basic system. Once you have this wired up you can uncover the panels and fine tune the orientation. You should now have an led lit on the charge controller indicating that you have power input. Make sure that you have quick disconnects for the bilge pump, as in alligator clips. Do a clean, safe stable job of your installation and have adequate ventilation for the battery. Wait until the charge controller shows a complete charge before using the system to power the pump.  OK, that takes care of the install.


I use this bilge pump http://www.amazon.com/gp/product/B000R4UBPS it is low wattage and moves just the right amount of water to make my auto siphon function properly. Also I have an aerator http://www.amazon.com/gp/product/B000HASBFE that is in use at all times, unless I am without ac power.  For aeration I have the tubing split with a T so that I can switch on the aerator when the ac power goes out.  So water is still being pumped into the grow bed and the fish are getting plenty of air. I angle it down more than this. I took the pic this way to dramatize the aeration. The hose on the left is coming from a rain barrel that I use to keep the fish tank topped off.

Back to the PV system for a few pointers; it is important to keep the glass clean. When the glass gets dirty the number of photons that reach the cells is reduced and this is known as soiling. Just spraying the dirt off with a hose is good enough.

Also, PV works better in cool weather. The hotter the panel gets the more inefficient it is. I run completely off solar two days a week to make sure that everything is working properly.

I also use the bilge pump to keep the bottom of the tank clean. I have another hose that I attach and push the pump around to suck the fish poo up into the grow bed. Hope this has been informative and given you ideas for your own setup. Next time I will be writing on companion fish for tilapia.

This is a reprint of an article from before the site was hacked. Sorry, I don’t know the actual author. JCO

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