I feel like I've just about beat this solar aeration horse to death, but I came across another pump and now I'm thinking this may be a viable option.

This continues from the previous discussion here: http://forums.pondboss.com/ubbthreads.php?ubb=showflat&Number=403945

So a quick recap... I pretty much had a solar system designed, but the problem I was running into is that the pump I was looking at (good for my 1/4 acre pond - http://www.123ponds.com/pa10w.html) would pull slightly too many watts (173) for the other components (solar panel, inverter, etc.) which are 150 watts.

Well, I was at harbor freight yesterday and saw this compressor:
http://www.harborfreight.com/1-5-hp-58-psi-compressor-and-airbrush-kit-95630.html

Well looking at the specs, it appears this $89 airbrush compressor only pulls 130 watts and is quite a bit more powerful than the pump I linked to above.

So my new setup would be:

Solar Panel
https://www.renogy-store.com/Renogy-150W-12V-Mono-Solar-Panel-p/rng-150d.htm

Power Inverter (Eliminates the need for batteries)
http://store.mwands.com/charge-controllers/12-volt-suntaqe-pwb-charge-controller-with-inverter/

Compressor
http://www.harborfreight.com/1-5-hp-58-psi-compressor-and-airbrush-kit-95630.html

50' of 3/8" Weighted Hose
http://www.diversifiedpondsupplies.com/50-ft-coil-38-self-weighted-airline

Diffuser
http://www.123ponds.com/dm2.html

All and all $565

Yay or nay?

I am not an expert but, I still don't understand why you are using an inverter to eliminate a battery. Why not just wire the solar panel direct to a suitable compressor motor? Still no battery. That's how my solar attic fan is wired - direct to the fan motor.

The pump is AC, so I need to plug it into an inverter. The DC pumps that are large enough require too much wattage. I would need an array of panels if I were to do it that way.

I made a diffuser that reduces backpressure on the pump so the pump doesn"t have to draw as much power. I wonder if that would help. Basically, you plug the airhose into a 3 in. PVC pipe 4 inches long capped (just drill a hole big enough to jam the barbed fitting in the side of th pipe just below the cap and use waterproof caulking to glue it in). Drill a series of 1/8 inch holes all through the cap to diffuse the air. Place the open end in the center of a metal pie pan and secure it with two small angle brackets. Use three 1 ft. stiff metal straps with holes drilled in each end to secure a 2 ft. piece of 6" PVC to the pie pan so there is about 3 inches between the drilled cap and the bottom of the 6" PVC. Fill the pie plate with concrete. The air rises through the 6" PVC pipe creating a venturi effect. It seems to move more water than my old stone diffusers, costs a lot less, and my pumps (and vanes) last a lot longer.

Hmmmmm. Now you have me thinking DIY diffusers. Ha.

What if you took a foot long piece of PVC, cap the ends, drill a bunch of holes in it and cover it with a couple of these boom mic covers (for lots of bubbles, haha).

http://ecx.images-amazon.com/images/I/51hoPT2AJuL._SL1001_.jpg

Then just attached the pvc pipe with a conduit clip to a box filled with concrete or whatever just big enough to sink it.

Edit- If I'm insulting your intelligence here, I apologize!!!! And I tip my hat to you for your hunger of learning... Try digging into a little research on an electrical component called an Linear Current Booster or simply LCB. I think your DIY options may open up a bit

mnfish, I'll be the first to admit my intelligence in this area is lacking to say the least, so no need to apologize!

Linear Current Booster? Great, another component to throw into the mix. Thanks a lot!

Okay, so I can run the solar panel directly to the pump through the LCB, right? And the LCB will only let the pump kick on when it has sufficient amperage to keep from burning the motor up.

No need for an inverter or battery...

Am I understanding this correctly?

FWIW IMO A DC motor can run variable speed no problem. All that will happen is it runs slower when you have less sunlight and faster when you have more. An AC motor is more efficient but a DC motor can do what you want.

You got it, sir.

I will give you my $600 LCB/compressor R&D mistake for FREE. If you go the route of an LCB, make sure it is built for the operating voltage of the compressor you intend to run. Off the shelf 12V LCB's are usually set above 12V and out of the operating voltages of a lot of 12V DC compressors. The compressor will run wayyyy to fast and pump failure will occur prematurely.

Okay, so how do I know how many amps the LCB should be? Does it just need to be equal to or greater than what the pump draws?

Here is one guys setup.

Solar Air system

Winter operation
He changed from DC to an AC linear pump with inverter.

https://www.youtube.com/watch?v=aoSVUXBEO28&list=PLzNGe4RIH2pFybPJgIIAp3hXsdVmpDgKf&index=12 Building a battery box for the system.

https://www.youtube.com/watch?v=4JSZSZR0qTU&index=13&list=PLzNGe4RIH2pFybPJgIIAp3hXsdVmpDgKf Without batteries.

https://www.youtube.com/watch?v=kZ1BzbzdrGY&index=14&list=PLzNGe4RIH2pFybPJgIIAp3hXsdVmpDgKf controller for no battery use



Interesting.

I'm sorry if I wasn't very clear. LCB's are for DC motors only. No AC!

Sizing is very simple. Whatever your maximum draw from your load; set the LCB 20% to 25% higher for a factor of safety. For example, if the compressors has a start up draw of 8 amps spec. the LCB at 10 Amps. Usually the LCB's are fused but I suggest you fuse at the compressor as well. Just in case.

Please keep in mind my expertise is very limited here...I am a mechanical engineer and most of my electronic knowledge is self taught. Fair warning and be aware. Kind of like when a machinist see's me walk into the shop and start using the tools.