Pond Project

[Ohio Fisherman]

Looking to set up a batteryless pond aerator.
I do not need it to run after dark or when it is cloudy. It just needs to start on its own when it has enough power.
I have a pump that is 3.9 amps, 688 watts and 115v
I was thinking I would just need about 1000w of solar panels and 1000w inverter, connect it all and I would be off to the races. But then I see parts like inverter controllers, charge controllers, breakers, RV inverters, Hybrid inverters...
Anyone have any advice or product recommendations?

 

[FilterGuy]

You should consider using a DC pump instead. Your requirements are actually very simple to meet with a solar panel and a matched DC pump. (The impedence of the pump needs to be at a value that is close to the impedance needed at the Panel's MPP). Adding a charge controller and an inverter just adds cost and complexity you do not need.

Do a search for "solar pond pumps" There are systems ranging from less than $50 to hundreds of dollars. I suspect the less than $50 might be a bit unreliable.... but I also suspect the really expensive ones are over priced.

 

[Ohio Fisherman]

I have the 115v pump ready to go and would love to use it. It is larger than most 12v DC pumps because I am dealing with 12ft + depth.

 

[FilterGuy]

I have the 115v pump ready to go and would love to use it.

That pretty much forces you into using an inverter and the complexities it brings.
Most (all?) of the lower cost inverters require batteries...and that adds another large amount of complexity.

Definitely do some web searches for a battery-free off-grid inverter, it would greatly simplify things if you can find one, but I am not sure you will be able to find such a beast.

You will probably need the Panels, a solar charge controller, batteries and an inverter to run the pump. You should watch some of @Will Prowse older videos on building small systems.

 

[schmism]

I have the 115v pump ready to go and would love to use it. It is larger than most 12v DC pumps because I am dealing with 12ft + depth.

MPP 1012lv is a small 1000w 12v all in one. paired with a simple 12v FLA batt you could have a system that does what you want.

 

[FilterGuy]

MPP 1012lv is a small 1000w 12v all in one. paired with a simple 12v FLA batt you could have a system that does what you want.

You would want to put a timer on the pump so it does not continue to drain the battery after sundown. Even Deep Discharge lead acid does not like to be anything but 100% charged.

Also, I would set the low voltage disconnect really high. That way the battery is just there to keep the inverter happy and is never drained very much.

 

[FilterGuy]

I have the 115v pump ready to go and would love to use it. It is larger than most 12v DC pumps because I am dealing with 12ft + depth.

The depth of the pond is not the driving factor. If the Feed pipe is properly sized, the height above the surface of the pond is going to be the primary concern for specifying the head the pump needs to overcome.

If you are still concerned, there is a simple way to pull from the bottom of the pond without pumping from the bottom: