solar panel for sump pump

[lhpjennings]

We run two to keep our property from becoming a vernal pool in the rainy

season, but our house does not have a garage or basement to flood. So my

idea is to use solar to operate the pumps, so we don't get these huge bills

in the winter for running (2) 1/3rd hp pumps for day after day.

[ghurd]

I put in quite a few of these.

I like the Attwood pumps and matching switch.

For low head, like 4' from where the water is to the pipe it goes out, I use the V625.  It is stunning how much water a V625 can move 3' high for only 1 amp, over 400 gallons per hour.

For a higher head I use the V1250. About 7' and 500 gallons per hour, or 3' and 950 gallons per hour, with 2.6 amps.

The only problem is they will wear out with continious use in about 3-5 months.

They do not move the quantity of water a 1/3hp pump will.  But they move a lot more water with a lot less power.  Less power means less battery and less solar panel, and that means a lot cheaper.  And the pumps are cheap, as are the matching switches.

They can be run straight from a well matched solar panel, but the sun doesn't shine while it is raining.

Just 0.02

G-

[eureka]

You can run a pump from a solar panel without a battery if you use a dc-dc converter (like the mini maximiser from the ATA) to match the motor load the the panel. http://www.suburbia.com.au/~mickgg/minimax/minimax.htm

http://shops.bizarsoftware.com.au/ATAShop/catalogue/category16/category37/product87

[ghurd]

Not at night.

[eureka]

Yes, but that wasn't the question ...

[ghurd]

Good point.

G-

[lhpjennings]

The nice thing about our situation is we

can wait for the sun to be able to

pump, because the standing water does

not reach the house.

Thank you all for the great ideas....

The minimaximizer is a fab concept.

I only hope I can persuade my husband to

go for it.

Cheers....

[lhpjennings]

Ghurd, I liked the suggestion for the attwood pumps. Go you need a battery

to run from the panel to the pump, or can you direct tie?

[ghurd]

It could be direct or with a LCB.  Direct could have some issues.  LCBs are kind of pricy.

I would want a battery.  If it is raining for 3 days, the PV would only run when there was enough sun (and it IS raining).  A battery would give a big jump on how much water could be pumped in those 3 days, using last weeks sun instead of next weeks sun.

You do need the automatic switch.  The pump will wear/burn out very fast if there is no water to pump.

The 'perfect' system around here would be a 32~50 watt PV, charge control with LVD, 85~110ah battery, the switch, and 2~3 pumps. (the switches last a lot longer than the pumps!)

Depending on where you are and what pump, the PVs could need to be a little bigger.

The head would determine the proper pump.  Make the discharge large.  Say you go with the V625 pump with a 3/4" outlet, then run 3/4" only a foot to a 2" pipe to carry the water away.  It works a LOT better that way and uses less power.

(I put in a temporary garden irragation system with 150' of 3/4" garden hose, about 30" of head, and barely a trickle came out while the pump was using a lot more amps than normal)

G-