Solar powered water pump (kit?), for the veg garden

[difflock]

I got a 600 gall water tank situated comfortably above head height, and water about 3.0m below my feet, say a couple of feet deep in a 1.8m dia conc manhole ring.

so looking to raise the water say 6.0m

powered by Sunlight

 

I had been using a 230V submersible pump, which has died recently.

 

Anyway, Solar is more elegant.

 

marcus

[woody paul]

What about a 12 volt fuel transfer pump, battery and a solar trickle charge panel. 

[AHPP]

What about a 12 volt fuel transfer pump, battery and a solar trickle charge panel. 

Could you do that with a 10p resistor rather than a £30 battery and a £20 charge controller? The pump would only run when the sun’s out but would be effectively automatic and simpler + cheaper. You could unplug/switch the pump off when not wanted or even just put a bit of cardboard over the panel.

 

[difflock]

APHH?

Sounds like my kinda "engineering", electrical or otherwise, but  please explain how the 10p resistor works?

I had origionally "picked" a Shruflow 12 V pump, see link;

 

https://www.ebay.co.uk/p/SHURflo-Caravan-Marine-Water-Pump-2095204412/1112679694?iid=171547564513&chn=ps&adgroupid=54682298551&rlsatarget=pla-413984953583&abcId=1133906&adtype=pla&merchantid=101748807&poi=&googleloc=9045175&device=c&campaignid=1058607774&crdt=0

 

And was looking for suitable solar panels to "drive" the pump directly, i.e.  without a battery, 

because with 600 gall of storage, and only needing water to water the garden when the Sun is shining,

I should be able to get enough current/voltage to pump when the Sun is shining, and be able to accept the pump not running during the dull periods.

But prob need some "black box" electronics to protect the pump from low voltage, thinking an automotive related "battery guard" device between the solar panels and the pump.

a marriage made in heaven, so to speak.

 

cheers

marcus

 

 

 

 

Edited May 5, 2018 by difflock

[openspaceman]

43 minutes ago, AHPP said:

Could you do that with a 10p resistor rather than a £30 battery and a £20 charge controller? The pump would only run when the sun’s out but would be effectively automatic and simpler + cheaper. You could unplug/switch the pump off when not wanted or even just put a bit of cardboard over the panel.

 

Yes no need for a battery but maybe some sort of current control other than heating up a resistor.

 

How about nicking a super capacitor from a pimped up Corsa and having a relay running the pump only when the capacitor is at 12V. This way the motor isn't draining current below its stall speed.

[difflock]

 

https://www.amazon.co.uk/Photonic-Universe-controller-battery-caravan/dp/B008BV8CIW/ref=sr_1_2?ie=UTF8&qid=1525532628&sr=8-2&keywords=5a+12v+solar+panel&dpID=512aYDf%2BQRL&preST=_SY300_QL70_&dpSrc=srch

 

This looks like a likely solar panel, to drive my 4.5 Amp (dry mounted) Shurflo pump ?

 

thanks for the interest and input guys

 

mth

Edited May 5, 2018 by difflock

[AHPP]

I just had the broad idea for not using a battery.[mention=33807]openspaceman[/mention] sounds like he knows more about it than I do. I’d be interested to read his component list and why limiting current is more important than limiting voltage (my panels are 250w and 35v ish open circuit so thought that would need regulation down to 12v) if he chose to post one.

 

[openspaceman]

54 minutes ago, AHPP said:

I just had the broad idea for not using a battery.[mention=33807]openspaceman[/mention] sounds like he knows more about it than I do.
 

 

Probably not

54 minutes ago, AHPP said:

 

I’d be interested to read his component list and why limiting current is more important than limiting voltage (my panels are 250w and 35v ish open circuit so thought that would need regulation down to 12v) if he chose to post one.

 

I doubt even 35V would break down the insulation in the 12V pump coil but over current could easily do damage.

 

You have to consider the internal resistance of the panel also so if that is high relative to the coils of the spinning motor (because of back emf the motor will draw less current when spinning than when stalled) the open circuit voltage will drop away. If you have the super capacitor in circuit it will store charge  until there is enough to run the motor in a spurt. Once the voltage drops to below that necessary to keep the motor running it cuts off and the panel then charges the capacitor back up. It serves the same purpose of a battery but without the problems but unlike a battery which stabilises its own voltage to an extent it does need some control. You can do it with a resistor and Zener diode but that wastes power, so  if and only if the panel can produce more current than the motor can stand a relay and current limiter is the way to go. I'm sorry I'm not clever enough to   deliver a design off the top of my head.

 

If a resistor is necessary then a light bulb may be better as this has a decreasing resistance as the current drops.

 

I see Difflock has posted a kit with built in current limiter.

 

 

[AHPP]

Very interesting. Thanks for posting. You’re too modest.

[Macpherson]

Hi, interesting thread,..... I'm putting together a similar system to you to keep batteries charged for off grid power, I rarely find anything on Amazon to be cheaper than ebay, cheers. 

 

http://www.ebay.co.uk/itm/20W-solar-panel-kit-with-controller-for-camper-caravan-boat-20-watt-charger/122630270712?epid=16015680039&hash=item1c8d556ef8:g:EJgAAMXQwwlSABHG