Our System is now running on Solar power !!!! WOW

[Bob Vento]

I completed the solar portion of my system today and as of this minute the system is under the suns power. I've included a link to all of the pictures from this project, so far and the solar pictures are at the end of the images.

Here is a list of items used;

1 - Harbor Freight 45 Watt Solar Panel Kit                PAID $ 151.99 
http://www.harborfreight.com/45-watt-solar-panel-kit-68751.html

1 - 12Volt 45 Amp Hour Battery                                 PAID $ 88.00 
http://www.amazon.com/PowerStar-Power-Sonic-PG-12V42FR-PS-12400-Uni...

1 - Coleman 200 Watt Inverter (which I have had for years in my trunk) List $ 20.00
http://www.amazon.com/Coleman-PMP200C-Continuous-Power-Inverter/dp/...

1 - 20ft. Outdoor extension Cord                                PAID $ 6.00 at Big Lots

1 - 12 gallon Plastic with latching top container          PAID $ 7.00 also at Big Lots

TOTAL INVESTMENT ..................................................  $ 272.99

We are waiting to see if this will carry the charge overnight. Keeping our fingers crossed.

PICTURE link here > https://www.facebook.com/media/set/?set=a.2905296195502.2115978.135...

[Bob Vento]

I am using the ECO633 Submersible pump (45 watts I believe) running 24/7 with no timer.

I have a flood and drain system and have considered using a timer to allow the water to remain in the bed longer before draining. We have not decided as of this writing what we want to do.

[equalsandy]

I wrote this up for myself but thought I would share incase: a) it's useful to you b) you see a mistake and can correct me:

On our aquaponics system we will have a 50 watt water pump and a 12 watt air pump. We will also run some peripherals like the monitoring system (about .5 watt) and a light available for use at night (8 watts). So I am basing our electric needs on 100 watts to give us almost 30% headroom. Based on the math (100w/12v * 24hours) we need 200 amp hours to run the system for 24 hours. Deep cycle batteries are generally rated in Amp Hours so we know we need 200 amp hours to run for a day and 'conventional wisdom' dictates that an off-grid aquaponics system should be able to stand alone with no input (a bad storm providing no sun) for 5 days. So the ideal setup would have 1000 amp hours of battery. From what I can tell marine deep cycle batteries tend to be rated between 100 - 200 amp hours so we would need 5 to 10 batteries but starting on 1 or 2 with grid backup is fine, assuming we have enough input.

If the system is pulling 100 watts then the 45 watt solar pack we have doesn't even provide 50% of the power needed to just run the system, let alone charge the batteries. We need 100 watts to run the system. 

As far as i can tell to charge the batteries…. 

watts / voltage  = charging amps 

45/12 = 3.75 amp

charging amp hour requirement = battery amp hour * 0.7 

200 * 0.7 = 140 

1000 * 0.7 = 700

So we need somewhere between 140 and 700 AH of charging depending on how many batteries we have

charge time  = ah / amp

Wisdom say one should average 5 hours a day of full sun charging. In order to charge our batteries in 5 hours….

140 / 5 = 28 amp

700 / 5 = 140 amp

to generate that much charging power 

28 amp * 12 V = 336 watts

140 amp * 12 v = 1680 watts

SO… in summary, to build a solar system that meets the 'ideal' safe criteria we would need 1000 amp hours of batteries with 1800 watts of solar panels to charge the batteries while running the pump. 

or minimal system needs 200 amp hours with 500 watts of panels. Presumably a system with 400 amp hours of batteries and 1000 watt solar would provide a reasonable cost effective place to start. 

Batteries seem to cost about $1.2 per 1 amp hour = $480

Solar panels seem to cost about $2 per watt  = $2000 

It is also worth noting that 1000 watts of 12 volt solar panels will typically be 10 100 watt panels each 3.5 foot by 2.25 foot so that's 80 square foot of panels. That's a good rain water catchment surface :-)

[Chris Carr]

You missed the point George. My point was even under completely unrealistic 100% perfect utopian conditions, it still cant handle the load. Also wanted to provide Bob with the basic example of calculated system load, because trial and error is not the most cost effective way of getting a solar system working, especially when system failure results in things dieing.

[George]

14 hours of charging is a lot.  Even on the longest day of the year here at 30N, that would be a lot.  Even if my panels could rotate and I had no trees, I wouldn't get that many good, peak charging hours.  I'm curious to see how this plays out.

"10w charge x 14h daylight = 140wh charge"

[Chris Carr]

For timed flood you should be able to get away with plumbing your pump directly into your drain outlet, just be sure to also have an overflow that can more than handle the inflow of water. Be sure both have media guards and don't run the risk of clogging. The bed should fill when the pump is on, and eventually overflow back into the tank. Once the pump is turned off, the bed drains back through the pump. Alternatively just have a drain that works at a lesser rate than your pump, and an overflow. When the pump runs, the drain cannot keep up and eventually the bed overflows. When the pump stops, the drain continues to do what it does, and drains.

In either case you will want to at least consider an airpump and stone for supplemental oxygenation. Depending on the wattage it still maybe just fine on the system to run it continuously while the pump is on a timer.

[Bob Vento]

Chris,

Thanks for all of your hard work and calculations on my solar project posting. It makes a lot more sense the way you explained it and I may follow your advise and do a timed flood and drain, using the solar system and see if that works on a 24/7 basis.

I won't be able to try this for a few weeks since we have some other plans in the works at the moment.

I will, however keep everyone posted on this new idea of yours and let everyone know how it works out. I am still trying to wrap my head around the auto siphon / non-auto siphon situation and how that works as well as all of those numbers Chris provided.

Regards,
Bob

[Chris Carr]

Great start on this project Bob. I am sure you will get it all figured out soon.

The way I would approach it is to be sure your pump is sized correctly and as efficient as possible. I haven't really done much in terms of comparisons but I am sure TCLynx (http://www.aquaponiclynx.com/) has figured which ones are the most efficient and recommends them through her site. Investing in an efficient pump is going to save you in batteries/panels.

Then you will need to figure 2 things in the worst case scenarios (accounting for battery efficiency decline over time) First, how much battery juice do you need to run the system during the longest nights of the season, typically winter. Second would be how much power do I need from the panels during the day to run the system, PLUS charge the batteries fully on an overcast/rainy day.

So some estimated numbers assuming 100% efficiency rates (and it for sure will not be).

35W pump x 10h darkness = 350wh

12v battery x 45ah = 540wh

 45w panels - 35w pump = 10w charging power

10w charge x 14h daylight = 140wh charge

I do not think you will be able to come close to charging your batteries during the day, even when the sun is full blast on your panels in perfect conditions. You will run out of power on your third night. (in reality the second night).

If you get rid of the auto siphon and run a timed flood of 15m per hour, your pumps drain is now 87.5wh and your panels charging power is (10w x .25) + (45w x .75) x 14h = 507.5wh charge.

During the night, your batteries wouldn't get below 83% charge and during the day, it will charge back to 100% in 2.5hours.

This will be much different under efficiency loss (clouds,dawn/dust, heat from the inverter and battery, etc), but i think your system may be able to handle it as it is today if you switch to a timed flood. Aeration may be a problem for your fish though. Maybe not. That pump wont handle the entire tanks volume of water in 15m, but you dont have enough media to stock your tank too heavy anyway. Passing half the water through the media per hour may be ok.

[Bob Vento]

Here is the long awaited UPDATE...

After burning up a couple of Coleman inverters, due to my specially bad designed gizmo to cross over from solar to commercial power automatically in case of lack of solar power.  I decided to give up on my goofy design and just see how long I could run on the solar regulator, another new Coleman inverter (hopefully the last one), and a fully charged battery.

(As a side note I have had one of the 12 volt compact flourecent bulbs running 24/7 off of the front panel of the solar regulator for a week now, and it lasts all night.)

Ok ... so Friday night my new Coleman inverted arrives, I unpack it and hook it up. Switch over from commercial power to solar power and see how long it will last.

It ran from about 4pm Friday until 2am Saturday morning, at which time the 12 volt bulb began flashing. My wife woke me up and I went out disconnected the pump from the solar system and reconnected it to commercial power. (The 12 volt bulb stopped flashing and lasted all night ... I guess there just was not enough stored power for the drain of the pump)

I think if I add another deep cycle battery to my system, it will last all night and be a 24/7 system. I am thinking about trying that in the near future.

That's it from Miami for now. Keep looking for ways to go off of the grid to run my aquaponic system.

Regards,
Bob

[David]

How many watts is your pump?.

[Vlad Jovanovic]

..."My hope is to use some sort of relay that will switch over power in the event of a power outage"...

I don't know if something like this would help you out at all...http://www.victronenergy.com/upload/documents/Brochure%20-%20Solars...