12V Solar PV System

[Bob Campbell]

I'm looking for advise about converting to solar PV.   I bought a 12V 200gph pump from Harbor Freight and hooked it up to a 12V car battery and a 2A charger to keep the battery topped off.  The pump says 'Not For Continuous Use' so it is currently only for times when the power goes out. 

But I would like to convert entirely over to a solar system.   I'm looking for a solar panel to provide enough current to run the 12V 6A pump.  I'm guessing I should look for an 18V panel, and a 12V charge controller.  Any advice or recommendations would be appreciated.

I'm also hoping someone will direct me toward a 12V pump that is built to run continuously.  I have found a few, but the prices are outrageous.  Is there anything for $100.00 or less?

[Bob Campbell]

This looks good to me.  30,000 hr of use, and only 1 amp at 12V.  The Harbor Freight pump is really noisy while this one is only 35db.

[Dave & Yvonne Story]

Bob,

during the summer I run 2 tanks and grow-beds on solar alone.

Currenty, because of the heaters I use, I only use my pv panels in the morning and the early evening.

So, what you are asking is easy to do.

 

I uset my pv power into a 8 12vdc battery bank configured to 24vdc and convert that to 120 vdc.

let me know if I can help

Dave

 

[Bob Campbell]

Your system has the advantage of 120V but I'd like to avoid the inverter by sticking to 12V. 

The DC40-1245 pump I found looks like a better choice than the Harbor Freight pump, but I still need to find a small PV panel and charge controller.

The way I understand 12V PV systems is that I should need slightly more than 14V to keep the battery charged.

Am I on the right track to look for an 18V PV panel?  

Dave Story said:

Bob,

during the summer I run 2 tanks and grow-beds on solar alone.

Currenty, because of the heaters I use, I only use my pv panels in the morning and the early evening.

So, what you are asking is easy to do.

 

I uset my pv power into a 8 12vdc battery bank configured to 24vdc and convert that to 120 vdc.

let me know if I can help

Dave

 

[George]

I'm using three of these with a 1.7A ShurFlo bilge pump running continuously - two AGM deep cycle.  Solar is a tough nut to crack with short, cloudy days.  I keep a 1A charger on it all the time lately - it comes on at night, generally.  Wholesale Solar is where I bought my last controller.  The 1A pump you found looks interesting.  Let us know how it works for you.

[Dave & Yvonne Story]

controller, & inverter & PV panels

I did pricing on ebay and Amazon..

Then decided on the item and found the best price..

It is all a learning experience for me.. I am having fun..

I have 2 12 vdc SHURflo RV water pumps and 2 12 volt marine aerators, but I have not installed them..

I am interested in your experience..

[Bob Campbell]

@George  - Thanks for the details.  I'm going to use a 30W panel.  It sounds like a larger panel would be better for those cloudy days, but I don't want to invest much more money in this project. 

By the way I recently bought a battery additive called Charge-It, the active ingredient in Charge-It is aluminum sulfate

There are others called Inox MX2 and Battery Equaliser which contain cadmium sulfate as the active ingredient.

I have no experience with the last two, but Charge-It did appear to restore two weak batteries.  I never did a load test so all I can base that on is the fact that I no longer have trouble starting my car.

[Matt T.]

Have you checked out Northern Tool, and Equipment? I have also seen a few sump pump designs used for back-up. They kick up to 1350 GPH, so you may need to vent some of this back into the ft. This would take care of any oxygen issues to. Harbor Freight has some solar panels, and controllers for a cheap price. That is as far as cheap goes in the solar market anyway..... You'll want to charge a deep cycle, or an AGM with at least 10 amps to fully charge it, otherwise you're only utilizing a portion of its holding capacity.

[Matt T.]

Does anyone have any ideas on utilizing some kind of a switch to turn on a back-up pump after a power outage? The only thing I've come up with so far is a photocell facing a small LED night light, so when the power goes out, so does the light. This would at least signal the photocell to activate. I still need to work out how this will activate the pump though?

[Randy]

You could use a double throw relay with a 120 V coil to turn on the pump. I use a inexpensive power supply, a powergate and an inverter for battery back-up purposes. The powergate charges the battery and switches to battery power when the power goes out.  http://www.powerwerx.com/batteries-chargers/super-powergate-backup-...

[Matt T.]

Thanks Randy. Looks like a good option. Can a person still wire in a solar charger and still be able to charge through this devises charger, or would I just not connect the devices charger? I would like to have the solar option for extended outages if it should arrise.

[Randy]

Matt the powergate requires a 12 V input source, the solar cells would work for that IMO. The problem is connecting a Power Supply and Solar Panels at the same time. They would have to be isolated some how because PSs don't like voltage on their output when the AC is off. You might be better off splitting the system. Say run the higher wattage water pumps off the Powergate and PS and the air pump off the Solar Panels. The drawback would be the need for two batteries and two inverters. I think you could easily size the Solar set up to run the air without need of any AC. Please keep us informed of your progress. 

[Dave & Yvonne Story]

yes very interesting project.. thank you