Not as simple as pumping A to B??

Hey Folks,

I’ve been reading this forum for a while now and just took the plunge and joined!

I’m trying to set-up a small irrigation system around my house and keep hitting road blocks!

There is a stream adjacent to my land but I can only gravity feed to just below the house. So I got two IBC (1000L) tanks and thought I would collect the water in a tank below the house (tank A) and pump up (approx. 20m head - approx. 50m pipe) to a tank above the house (tank B) so I can feed the irrigation system EOD (drippers) and have some water (tap/shower) by the house.

I’m off-grid so can’t use an electric mains pump, and y neighbours are not keen on me getting a petrol pump (quick solution), so I’m going down the solar pump rabbit hole.

I have so far two 230W panels (see attached for spec) and the IBC tanks as mentioned above. Luckily I have a friend in the Solar industry so have asked him to spec up a pump for me, basically asked him what is the most powerful pump I can run off those panels. My plan was to feed tank A and plumb an overflow pipe, then just pump up to tank B as and when needed but I’m sure there is a better setup. Ideally I would have the tank above the house constantly filling, could I arrange it so that is possible? Even if it's super slow, could take a whole day to fill, since I only need the water EOD for a few hours. That way I have a full tank most of the time except after I irrigate, and I could utilise the overflow in and around my house.

Great to finally join the Forum and look forward to hearing any responses.

Lots of Love,
Rich

Rich your plan reads well, as for petrol you can get some very small petrol pumps that are quiet.
A  few ideas to think about;
- install the largest pipe from the pump that is practical
- If you go higher up the hill you will have better pressure for the drippers
 because many dont work well with gravity feed.
- I have seen really good solar pumps and I just cannot recall the details, but they work with panels.
 They cost about $AU2500
- sometimes if tanks overflow too often they cause erosion unde themselves and fall down.

The most important thing about the pump for your situation is how high it can pump (the "head"). You want it to have a higher maximum than your pump-to-tank height, or it will never be able to fill the tank. As you approach the maximum head, the volume pumped per minute or hour will decrease quickly to nearly zero.

Our garden water system is as such

our 12v water pump is about 5 feet from our large pond. It pumps up about 30' of head and fills a 300 gallon tank. It then flows down to the garden via gravity. When the sun is out the pump runs off of 130watts of power.
The pump itself can move about 300L+ a day.

it runs directly off the solar panels, there is no battery or controller. It has a switch to shut it off when the tank is full.

I wouldn't consider the 12v pump a "solar pump" its from an irrigation store. Little pressure pump.

Something to consider is the PEP program. They have a Set up a solar water pump system

jordan barton wrote:Our garden water system is as such

our 12v water pump is about 5 feet from our large pond. It pumps up about 30' of head and fills a 300 gallon tank. It then flows down to the garden via gravity. When the sun is out the pump runs off of 130watts of power.
The pump itself can move about 300L+ a day.

it runs directly off the solar panels, there is no battery or controller. It has a switch to shut it off when the tank is full.

I wouldn't consider the 12v pump a "solar pump" its from an irrigation store. Little pressure pump.

Something to consider is the PEP program. They have a Set up a solar water pump system

Thanks so much for your feedback folks.

So it seems by your set-up Jordan I should have plenty of wattage (2 x 230W panels) to power a small 'solar pump', but I'm not sure I can run a 12V pump as my panels are higher voltage 30 volts max?

I like you have a switch to shut it off when the tank is full, I guess that's a system in itself? I'm thinking I'll use a submersible pump with float valve so the pump will never pump air, and just put an overflow pipe on both tanks.

I think I've got all the pipework and fittings figured out it's just choosing the right pump which will work off the panels and give me that 20m (65 ft) of head . . .

Although the more i think about it I like the idea of running a small pump like the one pictured (they are considerably cheaper than submersible), and having a shut-off switch when the upper tank is full . . . so it's only on when needed . . . interested to hear about the shut off mechanism Jordan . . .  

The shut off mechanism is a simple pressure switch.
When the required pressure is achieved, a rubber disc swells enough to operate a switch.
They are very simple and I found the rubber disc lasts about 10 years before needing replacement.
So it pays to get a couple as spares and keep them away from air and light.

A pressure switch at the pump outlet would roughly work, though it would have to be a precisely adjustable one to pump until the tank is just full and then shut off.

A float connected to a switch in the storage tank would very easily fill to exactly the height desired.

hey folks

so I grabbed a few more bits at the builders yard today and explained my system to them . . .

they reckon i have reduced the pipe size too much / too many times? there was already 100m of 1 inch & 100m 1.25 inch laid, I used 0.75 inch to extend to my IBC and 1.5 inch to extend to the pool where I'm hoping to draw the water. So it starts with 1.5, then 1.25, then 1, then 0.75, as I thought it was ok to keep getting smaller, just not bigger.

They think the syphon won't work like that and i need to use only two sizes of pipe?

Also I'm guessing 400m of pipe is too much to start the syphon by mouth, what do people use to kick start a long distance syphon? Manual pump of some kind?

the reason it's more of a syphon than gravity feed is the pipe is going down into a pool, which I can't enter from the side as it's solid rock . . .

it's a pool in a series of pools/waterfalls as opposed to a long stretch of stream/river.

Anyone tapped into something like this?

I am confused, is it possible to draw us a plan so we get a handle on the requirements.
\ We seem to have gone from a pump to a syphon.
There are syphon starters about.

drawing attached hope it's visible enough

Sounds like a "ram pump" is what you need.  If you have good enough flow in your stream, it will pump water uphill just fine, no electricity needed.  I saw one on homestead rescue where they pumped uphill with only stream power.

Yup, a RAM pump sounds like the ticket. If you have sufficient fall from the source (10m is plenty, it's doesn't take much) and volume they do quite well. If you take that route, since these pumps depend on the kinetic energy of intermittent moving water you should probably keep the 1.5" (or 1.25") all the way down to the pump and then whatever is recommended, depending on the capacity of the pump, for the outflow side to your uphill storage tank.

Going across the neighbors property? Hmmmm?

Dean Howard wrote:Sounds like a "ram pump" is what you need.  If you have good enough flow in your stream, it will pump water uphill just fine, no electricity needed.  I saw one on homestead rescue where they pumped uphill with only stream power.

aren't they quite noisy I heard though?

I can syphon water to the house terrace (just need something to get the syphon started) and then I have two solar panels sitting there which I could hook up a small 12-24v pump to pump up and fill the storage tank up top . . .

I'm not sure I need to change the pipe sizing 🤷‍♂️

Rich, you could possibly start the siphon by pumping some water back to the stream from tank A to refill the pipe. This might require some clever plumbing with bypass valves, but ought to work as long as tank A doesn't run dry.
Seems like metering your supply from the stream to match your usage, would allow the siphon to just run constantly and *never* break, require re-priming it?
If you had excess flow at tank A could you use it? or return it back to the stream farther downhill? (return of excess would negate need for metering)
If you could pump excess water to tank B, could it irrigate "automatically"? using swales or such? (tank B would then be a reserve)

Ram pumps make noise, but not loud... my father hooked one up to our spring outflow decades ago to pump the 600' or so and 20-30' uphill from the pump to our house. It sounded like a repeated shhh-chok shhh-chok, which could be heard clearly from ten feet but not from 30'.

How high does the pipe need to rise from the stream surface before dipping down to the bigg lower run? That is the only siphon that I can see, and if anything like scale, is probably not a big deal. If you can include a priming pipe so you can pour water into the upper end and start to fill the lower run, it should work constantly from there.

The inlet pipe size of a ram pump should be large and constant, but since a lot of the flow is discharged from the pump to air, the output flow is much less and pipe can be smaller. Where would discharge water from a ram pump go in your situation? Would there be any use for it?

Kenneth Elwell wrote:Rich, you could possibly start the siphon by pumping some water back to the stream from tank A to refill the pipe. This might require some clever plumbing with bypass valves, but ought to work as long as tank A doesn't run dry.
Seems like metering your supply from the stream to match your usage, would allow the siphon to just run constantly and *never* break, require re-priming it?
If you had excess flow at tank A could you use it? or return it back to the stream farther downhill? (return of excess would negate need for metering)
If you could pump excess water to tank B, could it irrigate "automatically"? using swales or such? (tank B would then be a reserve)

thanks Kenneth, I think after a day on YouTube yesterday I have figured out how to start the syphon using just a tee piece and a bucket.

I'm going to see how high I can bring the syphon this week.

Re excess water/overflows to keep the syphon running, I thought I could make use of excess water from Tank A but need to double check this as it's a long way back down to the stream from my house. I'm installing dripper irrigation from Tank B which could be running constantly while the sun is out and the solar pump is moving water up from Tank A to B, that could work well.

I'm also considering a Ram Pump close to the pool which could potentially pump water straight up to Tank B and negate the need for two tanks / solar pump install and prob overall less pipe and fittings, but it's more of an experiment I feel. Also like my previous post concerned about the noise of Ram Pumps.

Some pump math help.

2l minute is a tiny pump 30gal hr the pressure will be the important # on the pump.
The 20mm pipe us fine for 2l minute.
10m is 30 ft at 1psi per 28inches is 12.8psi make sure the pump will push 20psi / 15m

To direct drive a DC pump from your solar panels you will need a 24V pump. Or a charge / pump controller to step down to 12V.  Most likely you will end up with a larger pump ten you need.  Make sure it is protected from running out of water (tank A empty) and shut it of when tank B is full.  Tom