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Pump water with no electricity, no gasoline, just gravity!
Sound crazy or impossible? Don't worry, it does obey the laws of physics, but I'll try to explain the operation later. This instructable shows how to build a fairly simple water pump that needs no energy input other than water flowing from a higher point to a lower point. Most of the pump is constructed from PVC, with a couple of bronze pieces thrown in for flavor. I was able to source all of the parts from a local hardware store (Lowes) for a bit under $100.
To function, the pump does require a reasonable amount of water that will drop at least 3'-5'. The level that the pump can raise water to depends on the water's head (total drop the water will make).
This design was worked out by Clemson University.
If you like what I've done, please take the time to give it a rating, and I'd love to hear your input. Thanks!
Sound crazy or impossible? Don't worry, it does obey the laws of physics, but I'll try to explain the operation later. This instructable shows how to build a fairly simple water pump that needs no energy input other than water flowing from a higher point to a lower point. Most of the pump is constructed from PVC, with a couple of bronze pieces thrown in for flavor. I was able to source all of the parts from a local hardware store (Lowes) for a bit under $100.
To function, the pump does require a reasonable amount of water that will drop at least 3'-5'. The level that the pump can raise water to depends on the water's head (total drop the water will make).
This design was worked out by Clemson University.
If you like what I've done, please take the time to give it a rating, and I'd love to hear your input. Thanks!
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Signing UpStep 1Bill o' Materials
Before you can really do much, you've got to go out and buy some stuff. One of those sad facts of many projects. But if you want to build this (and it's a lot of fun to see it work), print out this list and head to the plumbing dept of your hardware store.
Materials for the Pump
Connections Note Read through the instructable and understand all the pipe-fitting connections that will happen before buying materials. The store may not have exactly what you're looking for, and you may have to improvise. I wound up getting some different parts because my local store didn't have the exact parts I was looking for. This usually appears in the form of not having a threaded fitting, but having a smooth pipe connection, or vice versa. Not a problem, you can figure it out.
Installation Materials
Materials for the Pump
- 1-1/4" valve
- 1-1/4" tee (buy two of these)
- 1-1/4" union
- 1-1/4" brass swing check valve
- 1-1/4" spring check valve
- 3/4" tee
- 3/4" valve
- 3/4" union
- 1-1/4" x 3/4" bushing
- 1/4" pipe cock
- 100 psi gauge
- 3/4" x 6" nipple
- 4" x 1-1/4" bushing
- 4" coupling
- 4" x 24" PR160 PVC pipe
- 4" PVC glue cap
- 3/4" x 1/4" bushing
- Short (4') section of 1-1/4" PVC pipe
- Old Bicycle Innertube
Connections Note Read through the instructable and understand all the pipe-fitting connections that will happen before buying materials. The store may not have exactly what you're looking for, and you may have to improvise. I wound up getting some different parts because my local store didn't have the exact parts I was looking for. This usually appears in the form of not having a threaded fitting, but having a smooth pipe connection, or vice versa. Not a problem, you can figure it out.
Installation Materials
- Long section of 1-1/4" PVC ("drive pipe", connects pump to water supply)
- Garden Hose (male end threads into 3/4" union, supplies pumped water)
- Bricks, blocks, rocks to prop up and anchor pump
- Shower Drain assembly (must be able to attach to 1-1/4" pipe, for attaching pipe to water supply)
- PVC Primer (I used Oatey Purple Primer)
- PVC Cement (Oatey again, just what they had)
- Teflon Thread Tape
- Hacksaw
- Measuring Tape
- Clamps
- Pocket Knife
- Lab gloves (keeps the chemicals on the pipe and off your hands)
- Bike Pump (to inflate the innertube)
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This is the latest design of the pump. Picture two shows the pump operating on the site.
many thanks
just some approximationss. i badly need it.. thankyou
sorry for not getting back sooner. Very busy these days (but that'll never change, will it?) Anyway, as far as your question about supplying 20 households. The short (and disappointing answer) is: it depends.
Mostly, it depends on how much each household would need, what your water supply looks like (how far the water drops, how fast it flows, how far below the houses the pump would be). Lastly, for supplying many houses, I would expect that you'd do better to build a number of pumps. I really don't know how well these scale (and the cost of larger materials would probably be prohibitive even if they do scale well).
Look around online, I think that there are some good calculators based on the water head (overall drop), flow rate, pipe diameter used to build the pump. Keep in mind that you'd end up pumping water to a storage barrel (located a bit above where the water will be drawn so that you have constant pressure) because these pumps don't do high flow as much as they do constant low flow. Hope that you're able to sort out your water needs!
thanks for the practical design and instructions. I have made mine with 60m of 40mm inlet pipe and 25mm outlet pipe, the drop is about 10 meters and the supply is about 20 liters a minute. I have only attached 100m of pipe to the outlet, going about 20 m uphill. Eventually I hope to get the water 80 m up the hill. The pressure is good, the brass valve snaps shut very quickly, problem is unless I break the pressure manually it stays shut. I have tried reducing the inlet pressure and angling the pressure chamber but no joy so far. I have not given up yet and have had great fun playing around with the ram. The parts cost me a lot less than expected, around 50$ (excluding pipes)
There is an almost identical pump for sale for an exorbitant price
http://www.aquaafrica.co.za/store/index.php?main_page=product_info&cPath=2_18&products_id=194&zenid=5a1dfaf3daf84a3a77b94289de5dbe4a
their pressure chamber is a lot smaller, does that make a significant difference?
cheers
First, as mentioned by one of the commenters below, sometimes priming the pump can be a bit of a challenge, involving repeatedly pushing down the flapper valve. I can't remember for sure, but I think that there should be a pressure spike then drop following the closing of the brass swing check valve. I think having some back pressure on the other side of the pump helps that pressure drop occur, which would allow the check valve to open up again. Make sure to also check the orientation of your plastic swing valve (just in case).
If you still don't have any luck with that, it's time to get a little more creative. It's possible that the static pressure of the water head is enough to keep the brass flapper closed, period. So perhaps we need to help gravity out, and add a spring that pushes down on the flapper to help it open up after closing. I've seen other designs that actually use compression springs rather than gravity to do the whole operation of the brass check valve. Perhaps you could use some hose clamps to fix an angle bracket to the side of the brass valve, and then run some allthread with a spring around it (and washers + nuts to hold everything in place etc) so that it would push down on the check valve when it's closed.
If you think of the brass valve as a spring valve that's just using gravity to provide the downward force, then you'll see what tilting the pump is doing. As you rotate the swing valve motion from inline with gravity to perpendicular to gravity, you're decreasing the spring force of the valve, so it takes less flow / pressure to close the valve. This is handy in low flow / pressure situations where the pump might have trouble closing the valve initially, but that isn't your problem. You've got too much of a good thing at the moment! We just need to figure out how to put it to use properly.
As far as the volume of the air chamber, it may well have an effect. Basically, the air chamber acts as a spring, storing some of the pressure of the water that's forced past the plastic check valve, and then releasing that to push the water in the outlet pipe higher. A bigger chamber is equivalent to a looser spring, but once the pipe is filled it shouldn't be a huge difference... But on this point I'm really not 100% sure.
While I don't have an immediate solution for you, I hope that some of this has helped. You're clearly up to the challenge, so let us know how it goes. Try out some different builds! Swap out parts, make your own, get a little crazy! And when you get it all working, toss up some photos, because that would be pretty cool. Good luck out there.
The Great Sphinx Of Giza
Water doesn't like to be compressed. And things in motion like to keep moving, unless something is there to stop them (friction or a wall). So, when you get a column of water moving down the inlet pipe at some speed, it wants to keep moving, but suddenly it's stopped by the brass swing check valve. Think multi-car pileup on the highway perhaps. Car 1 stops, car 2 slams into car 1... anyway, when the water is stopped, it causes the water pressure in that area to spike. Going to take a brief aside here, but just keep in mind that the pressure around both check valves has gone way up.
In an open column of water, pressure is determined by the height of the water level above the point that you're looking at. The equation is Pressure = Density of the Fluid * Acceleration due to Gravity * Depth of water. So if you had two pipes, one twice as tall as the other, both filled up with water, the pressure at the bottom of the taller one would be twice as great as the pressure in the other pipe. The only real important part of all this is that pressure at the bottom of some pipe depends on how high the top of the water is above the bottom.
So if we stick a hose on the outlet of the pump, it acts very much like the pipes that I was just rambling on about. The higher you lift the end of the hose, the higher water has to go to get out of the hose, and the higher the resulting pressure at the pump-end of the hose. Which is importantly right on the other side of the spring check valve.
OK, back to the fact that when the swing check valve closes, the pressure spikes on the inflow side of both check valves. As long as the pressure rises above the pressure on the other side of the spring check valve, some water will be forced past the valve, until the pressure on both sides is more or less equal, when the valve will again close. This happens over and over, each time pushing just a little water past the spring check valve, and slowly moves the whole column of water up the hose.
The height that the pump can lift water to is limited by the height that the incoming water drops from, based on the increase in pressure generated by the water stopping.
Righto, I hope I didn't bore you too much with all of that, and I hope that this all helped explain how these odd little creatures work. There are some other very odd / cool pumping methods out there that can do strange things just using water dropping some distance. Go and google "pulser pump" if you're interested.
I see why you suffer wear problems with your horizontal valve. Attached is a design that may help you. I don't think we should hijack Habolooby's thread here, so if you have any questions, you can ask me via pm or in my pump thread at http://www.instructables.com/id/Worlds_greenest_water_pump
We're building this as a project for 1st year Engineering. But there's a problem: whenever we attach the air chamber, the swing check valve refuses to drop (or be sucked down). It needs to be triggered manually everytime. Removal of the air chamber results in the pump automating nicely (albeit with reduced efficiency).
We're trying to grasp the physics behind why it won't work, but (unfortunately) have failed. Can you help?
Some specs: The drive tank is elevated 1.3m, connects to a standard hose, which connects to the 3/4-inch pipework. The chamber is two connected tin tennis ball containers (= 1m high; 10cm diam.)
Could the chamber be too *big*?
For your eventual thesis, maybe you can tackle the following phenomena:
http://www.great-pyramid-giza-pulse-pump.com/Vortex_Anomaly.php
It's not caused by the impuities in the water. I have an idea why it happens, but can't back it. That piece of pipe is still purple today, albeit somewhat faded.
Also note: In one of the pictures, the waste gate valve is open and no water is coming out. That's the valve sucked open and zero pressure (and zero water flow) at the wastegate valve because of the compression wave going back up the pipe.
Best,
John