Need Some Engineering Advice, PLEASE

[Harold in CR]

 I am trying to beat the rainy season, by getting my Hydro system mostly installed.

  I have dug a small pond uphill from the water source. It will be 4' deep and have around 9000 gallons of storage, but, be fed with possible 2 waterwheels, each pushing 2 piston pumps to push the water up to the pond. I plan on using the overflow for the generation, downhill. Hopefully, I will have 1500 gallons in 24 hr period of time, OR MORE.??

  First, the pond is right at 110' elevation, at 200 feet distance to the stream and waterwheel location. I have 2-4" PVC pipes set in concrete for the drain and overflow. I will cap the ends inside the pond, and let the overflow drop down a 4" pipe, into the "T" that attaches the drains to each overflow. That will drop the water to the generator site, just above and upstream of the waterwheel site. The spent water from the generator, can be piped right back downstream, to help the waterwheels, in case there is insufficient water available to run both. Figure to wear out the water, using it over and over and over. This is a second water supply, coming as a direct result of the first supply being piped to the waterwheels from the stream source to the waterwheels.

  Today, I was digging around below the elevation of the waterwheels location, trying to see how deep the bedrock is, because, I found out that the small dam I installed upstream, to put the 3" pipes into, that will feed the waterwheels, has less flow than at the location where I was digging. SOOooooo, I am thinking about putting a Dam at THIS location, and have it hold back a small pond, that would be 18' wide, X 40'+ long, X nearly 36" deep, throughout the whole pond area. There is plenty of room to build a small cement block, "powerhouse" at the base of the Dam. IT will be cement blocks, poured full of concrete, and tied into the existing boulder type rocks that are set into a "concretion" type mix, that looks exactly like moist coarse sand mix concrete. I can drill holes into this concretion, and put pieces of rebar in the holes, that will allow me to tied the blocks into the concretion.

  This whole dam will be 4' high by the thickness of the blocks, 4½", and span a distance of 4-5 FEET or so. Pretty small set up.

  What I am needing to find out is, I can figure the amount of power I can produce at the Pond overflow system, but, is it possible, I could put a drain pipe low in the dam, and have sufficient pressure to get the same amount of power, without the Rube Goldberg piping-waterwheel system   Just picture a MINI-Hoover Dam using this SPRING fed stream.

  I can supply all the photos needed, but, first, would like someone to try to figure out if there is sufficient FORCE of water pressure, to run a Pelton set up, at the discharge of the dam ??  AND how much power would be available from the info I have provided.  Anyone???  PLEASE

[Harold in CR]

Can't seem to find the instructions for posting photos  Maybe need to have an outside hosting source

[hydrosun]

As best as I can figure, you plan on using 4 feet of drop to run a waterwheel to pump water up 110 feet. If it was 100% efficient you would be able to pump about 4/110 of the water flowing over the water wheel up to the pond. You'll be lucky to get 1% of that water up the hill.  That's not a lot of water. Looking at you photo I'm seeing a small stream of water. I've no idea of your winter time flow. But it seems the 4 feet is all the head you have. The power available is 4 times the gallons per minute divided by 10. That is before the losses of pumping the water up the hill and back. Just for power is makes more sense to use the four feet into a turbine directly. Check the old otherpower forum for a wheel cage for hydro.  I don't know what  other plans you have  for the water storage, but pumping the water up the hill for power just wastes more power.
Chris

[Harold in CR]

 On the otherpower forum, there was a diary by Divebuddy. He built a water wheel using wheel chair wheels and metal buckets he made. He had very similar conditions, and was pushing 500 gallons per 24 hours, up a hill at 100'+ elevation, at 26PSI, I believe.

  I am planning to somewhat copy what he did. He is using 1 piston pump, and thinks 2 pumps would be very possible. That would possibly get 1000 gallons per 24 hours.

  I am NOT disputing what you have written. I am merely asking if what he did could be duplicated here.

  All day yesterday and last night, we had rain. Didn't measure how much, but, today I have AT LEAST 1/3 more flow. Right now, it is our dry season, but, could start raining steady at any time. It would be early to start now, but, Al Gore is in charge of Global Conditions, so, anything is possible.

  So, lets say I have a flow of 25 gallons per minute. IF I build a dam where the water is dropping in the photo, I can get 4' of dam wall, to hold back about 40" height of water, to allow for overflow when the rains come. I will try to check the flow later today, to see what the increase was overnight. I have a small test dam, upstream, with a 3" pipe running through at the top of the dam. yesterday, it was 1/3 full. Today, it was 2/3 full of flow.  I know I have many "seeps" through the roots of the trees and down on a bedrock, of sorts. That's why I am pretty sure I can up the amount of flow, IF I can build another Dam further downstream, at the photo location, and collect, AT LEAST, another 6-8 gallons of flow. All this, before the rains come ?? Then, I have about 9 months to see where I can improve on the set up.

  I can't find the amount of pressure buildup I can expect at the bottom of that dam. I have been all over the Internet, and have found formulas. They are great if you understand Algebra or Physics. I'm a mechanical type, not a Math type.  i KNOW it will be more than the drop pressure, correct   If so, what could I maybe expect, if I had a very efficient generator and Pelton wheel, or another efficient generator set up   I don't expect much, but, could I expect 1000 Watts per 24 hours

  The idea of pumping the water uphill, to the pond, was so I could raise Tilapia and sell them and eat a few. That water would HAVE to drain to keep  it from becoming stagnant, so, use the drop to run another Pelton set up. Once the expense of building the wheels and buying the piping is covered, The system would be essentially free running. Just need maintenance.

  I REALLY appreciate your response, Hydrosun, and hope you would continue to advise me. I am not about to give up on this project. I can't defy the laws of Physics, but, maybe I can tweek things here and there, to get some usable generation going, to AT LEAST charge my Electric Vehicle, when I get it finished.

[Ungrounded Lightning Rod]

Seems to me it makes more sense to make a hydraulic ram for this than to build a wheel.  Less to go wrong and similar efficiency.

A hydraulic ram is the fluid dynamic equivalent to a switching boost converter, trading high flow at low pressure difference to get low flow at high pressure:
 - Flow=== current.
 - Pressure === voltage.
 - Inertia in ram pipe === inductance.
 - Clapper valve === switching transistor.
 - Output check valve === diode.
 - Pressure tank === output capacitor.

They're simple and reliable - often running decades without attention.

Why do you need to pump the water up and store it before generating from it?  Do you intend to store it for months to save rainy-season power for the dry season?  (If so that seems like a very small storage area.)

[Harold in CR]

 Actually, a hydraulic ram was my first idea. I am very familiar with Rife Ram Pumps. My dad collected them for many years, and we took a couple out of the pits they were still operating in. There is not enough head to operate a Ram Pump. I would still have to double or triple run pipes to get enough head, and, they waste a lot of water.

  The one I built, I used a motorcycle wheel, and 17 buckets made out of 4" PVC pipe cut in half long ways and capped on each end. It should function as well as the DiveBuddy wheel does, maybe.

  Here is why the pond uphill.

 

The idea of pumping the water uphill, to the pond, was so I could raise Tilapia and sell them and eat a few. That water would HAVE to drain to keep  it from becoming stagnant, so, use the drop to run another Pelton set up. Once the expense of building the wheels and buying the piping is covered, The system would be essentially free running. Just need maintenance. Huh

 

[Ungrounded Lightning Rod]

Thanks.  I missed the paragraph about the fish farm.  Recovering the pumping energy as electricity when you dump the used water makes perfect sense.

[hydrosun]

If you can duplicate what the other person did you would have 1000 gallons per day at 110 feet, about 48 psi. A hydro running 100 gallons per minute would run 10 minutes a day. The power per day would be under 200 watt/hours (0.2kwh)  Spread out over the 3600 minutes per day it is less than 1/3gpm. Most hydro won't work on that flow. At that head the Harris hydro needs at least 3 gpm to overcome internal losses.
At 4 feet head the pressure is under 2 psi.    2.3 feet for 1 psi
 Energy in is always greater than energy out. You need more than 25 times as much water to pump the water up 25 times the height of the falling water. At 50% efficiency you would need almost 20 gpm at 4 feet to pump 1/3 gpm up 110 feet. So your 25 gpm is in the ballpark for pumping 1000 gallons water per day.
 You'll have to decide if the output is enough to justify the expense of a hydro, and figure out a way to automate a start and stop.    ( some sort of syphon arrangement?)
Chris

[Harold in CR]

 OK. NOW we are getting somewhere.  In the beginning, I want to put 2 pumps per wheel. I can re-route the water the first round, to be sure I get sufficient flow to get that 1000 gallons per day. I have room in the pit I built, to put 3 wheels. They are pretty cheap to build. That would give me a potential of 3000 gallons per day. Running the water downhill, through the turbine, and THEN, running it back through the wheels, will give me double the input. I can catch every drop of the downhill run, so, efficiency of the system stays steady.

  I can also catch the overflow from the wheels if I build the small 4' high dam. That will give me a chance to get more input to the pond uphill. I will probably build the dam with 2-pipes, and use that to drive maybe 2 more wheels for drop water, instead of trying to rig up a pressure pipe from the bottom of the dam ??

  I know it sounds like a lot of pipe and work, but, it's all in a confined area, so, rolls of 1" poly are cheap, and using 2-3 runs uphill from the pumps is cheap and easy. I also have 2-4" drain pipes out of the uphill pond, for whenever the rains and /or increased wheels put out more production.  Piston pumps are cheap and easy to build. Just need more check valves.

[ghurd]

Off Topic.  I already smacked myself for it.   

If the water change is for the fish, nitrogen etc, can circulate the deeper water to the surface for natural exchange of gasses with very little power using an air pump.
The bubbles lift the water.  Bubbles in a pipe lift water from where the bottom of the pipe is.
That should make less water change (pumping water) required per day.

Something like a DC8 aeration pump (12V 25W) or DC15 (12V 75W)?  Need the brushes regularly changed or the commutator is ruined.  Shop around (if you like that brand pump), the price differences are astounding.
Anyway, air pump to a diffuser in a pipe, something like this,
http://i701.photobucket.com/albums/ww20/ghurd1/Sketches/Air.jpg

G-

[Harold in CR]

 Thanks ghurd
 I am also thinking about the aeration. Actually a couple of those devices.
I am also thinking about raising Prawns in the same pond. They will digest the poo from the fish, but, I still want to use the overflow for generation. Once the water is uphill, why just let the creek water run unused   Might just as well use it, several times over

[hydrosun]

The water coming back down the hill will only be about 1% of the water used to pump the water up. It won't contribute much to pumping more water up the hill. It's pressure will be spent in a hydro turbine. so it will be left with 4 feet head.
Chris

[roosaw]

As a general rule there is NO advantage to moving the energy around trying to get more out of it.  Perhaps you have some other constraint (machanical limitation extracting the energy??)  I'm certian that your waterwheels extracting energy from the stream directly are your best bet to capture the most energy for your use.  Instead of pumping water up to catch it going down later (with at least three losses I can directly see) it is better to just regear your waterwheels to use the energy directly.
Summary of losses
Waterwheel pulling power from stream
pump friction
pipe friction going up the hill
evaporation losses sitting in the pond
pipe friction going down the hill
losses in the final water to electrical conversion

If you loose the pond then all you have is the final water ot electrical conversion.  Pretty much a no brainer from the engineering standpoint.

Why are you thinking a pond is going to be helpfull?

[Harold in CR]

 This idea has been re-routed. Anyways, to answer your question, about why I think the pond would be helpful.

 First, The water has no usable power as it is. I could have gotten 8' of head at 25GPM. That would pump water up to the pond. Then, the pond is supposed to have fish in it, so, regularly drawing the pond down, would allow more fresh water for the fish, and, may as well use what power IS available, at the 100' drop.

 The spent water would be run through a small alternator, UPSTREAM of the water pumpers. That way, I get to re-use the pond water a second time, and provide a little more flow for the water pumpers.

 Yes, it may not be very efficient, BUT, I needed to pump water to the pond, no matter what, so, rig up some battery charge from the discharge.

 Now, I have put in a second dam, 30' downstream from the first, so, all flow goes through the second dam, run through a wooden sluice I built, to channel the water THROUGH a hillside, where I have dug a ditch, to put pipe into, and then, I pick up an additional 16' of drop, giving be a total of 24' of head and, using all the flow I can get, including storm runoff. What overflow I get, will simply be runoff, over the second dam and down the original stream bed.

 This all comes from the neighbors spring, just uphill from my place. and, I only have 60 meters of property width, to get this all working.

[ruddycrazy]

G'day Harold,
                   If you have any decent wind there whynot just get 3 off 44 gallon drum, cut em in 1/2 stack em then couple and old car diff and 2 water pumps connected. So when ever the wind is blowing your pumping water. Over here in Oz it is an ol' favorite for farmers.

Cheers Bryan

[Harold in CR]

 Good idea, Bryan.
 The water is 100' down in a gulley. NEVER have any wind down there, due to the 50' high trees growing down the hillsides.

 My plan should work OK. Just need to get the neighbor, uphill, to stop washing his dairy floor down into the spring-creek.

 Looks like a giant open septic down there.  Talked with him, a couple days ago. He says "No Plata", no money.  IF I go to Synasa, the environmental branch of the Govt. They will rain hell down on this guy. It's prohibited to do what he is doing. I'm giving him fair warning in 30 days, to get this stopped, OR, he's really going to hate me.

 No problem, I have way more bullets than he does. 

[roosaw]

Or you could start a joint venture and take his bio mass and furment it into methane then sell it back to him as high grade compost.   Pretty simple equipment too.