Hydro choices, location and turbine type

[Apogee]

Very cool thread!

I would love to see more pics.  It'd be nice to see the penstock as well as more shots of the turbine while it's working.

Congrats!

Steve

[Jedon]

Thanks! Here are some videos I made of the process.
http://www.youtube.com/view_play_list?p=D9D9584BE7BF9815

[mike90045]

Thanks! Here are some videos I made of the process.
http://www.youtube.com/view_play_list?p=D9D9584BE7BF9815

Whoa !  Thanks,  Likely have to add some hydro for next winter.  I'll be skimming water off the top of my pond, with a 4" PVC pipe, and use 3" poly to feed a generator. 30' won't give me much, but better than flat batteries.

[mbryner]

Thanks Jedon!  Keep the posts, pics, and videos coming.   I found a thread of yours on fieldlines also and spent too much time reading it today.   Like Mike90045, I'll be installing some hydro next fall also.

[Jedon]

Will do, it's exciting and frustrating at the same time. Here is the last stuff I posted there:

I'm wondering if the input voltage to the charger is not high enough, it's right at the low end cutoff range, 108V. I'll put bigger jets on the hydro to get some more voltage out of it under load and if that doesn't work I'll lower the field resistance to keep the voltage up under lower flow rates.
This is the charger : http://www.iotaengineering.com/dls5413.htm
it does say 80% efficient so that would lower the 560W down to 450W, then the inverters are 97% so now we are down to 434W max, if the charger is producing less current at the lower voltage,
If it can push 13A into 54.4V, it can only push 11.7 into 49V ( battery bank voltage )? Or it makes 13A at 120V but only 11.7A @ 108? Combine the two for even less power?

Just throwing some silly ideas out, I have a Morningstar TS-60 PWM charge controller. Right now it's not hooked up. I have my PV going right into my batteries at 65V. I was going to hook my PV up to the TS-60, but should I instead hook the output up the IOTA up to it so that perhaps it trades some amps for volts and puts less load on the charger? Can I hook both the PV ( 65V ) and the IOTA ( 54.4V ) up to the TS-60 at the same time?

Anybody have some advise on how to tune the Harris unit? I have 1/2" nozzles and all 4 water inlets going and the pipe is staying full so water flow isn't an issue. Pressure might be? I only have 19psi. I played with the field adjustment on the Harris unit a lot today and didn't really get anywhere. I thought that if you turn it all the way strong then it's harder for the water to spin it so it spins slower and you get lots of amps but not as many volts, and it I make the field weaker then I get more volts but less amps. This doesn't really seem to be the case. At full strength at the turbine I get 8A @ 110V, when I go back to where the charger is 700ft away I get 105.4V and 5A. I expect the voltage drop but not the amperage drop, I though only voltage dropped over distance? I have 10g wire so I expect 10% voltage loss which would actually bring my voltage to 99V but it doesn't. ( from here http://www.nooutage.com/vdrop.htm ). I want to get as much voltage as possible to feed the AC IOTA charger which wants 108 to 132V AC which the 71% difference for DC means I need more like 150+V DC, not sure I can get that since the Harris unit is 120V DC rated, it's 208V open circuit but I can't get it above 112V loaded so far. Is there some way I can up the voltage electronically? I know I can't use a transformer since that's for AC. Should I stop wasting time and spend the $500 on an MPPT controller instead of the IOTA charger?
Thanks!!

[KeithO]

Hi Jedon
Excellent stuff.
Could it be that the charger is clamping the voltage at 108V , does the voltage rise as the battery voltage rises towards fully charged ?
What are you measuring the current with , and yes 8A at the generator should be 8A at the charger end, unless the meter is being fooled somehow or some power is leaking some where.  
Might have to test that old pump cable with a 500v meg/ohm meter
Also what happens when you turn one jet off ?

Cheers
Keith

[sailawayrb]

Hi Jedon,

I would first suggest calculating your maximum available hydro power and then quantify/address the other power system losses.  So I would first measure actual head (either static or dynamic pressure) and actual flow rate.  I believe you already measured your actual head being 19 PSI, however, you didn't state whether this was dynamic or static head?

Using the calculator in this link to calculate your maximum available hydro power:

http://www.nooutage.com/hydroele.htm#How

(which assumes an overall 50% power system efficiency...which is actually pretty close to your setup: 65% for Harris x 80% for IOT x 97% for inverter x 95% for wire = 48%)

and:

your measured 19 PSI head (which I assume/hope is dynamic pressure...i.e., measured water pressure with valve open and maximum flow of water thru the pipe),

your 400 feet of 3" PVC,

and assuming 90 GPM flow rate (about the maximum pipe flow rate for your run of pipe above which pipe friction head loss becomes significant...and which shows up as the recommended "Minimum Pipe Diameter" in the calculator),

your maximum available power is about 355 watts (256 kWH per month).

If your measured 19 PSI head is actually static pressure (i.e., measured water pressure with valve closed and no water flowing thru the pipe), then 80 GPM is about maximum pipe flow rate, and your maximum available power is about 253 watts (182 kWH per month).

This link provides the Harris nozzle setup recommendations (i.e., the number of nozzles to use) to maximize Harris efficiency given your available head and flow rate:

http://www.nooutage.com/harris.htm

This link (see nozzle selection section) provides Harris nozzle size recommendations given your available head and flow rate:

http://www.nooutage.com/hydroele.htm#Nozzle

Your head/flow rate appears to be in the range where either 2 (5/8"), 3 (1/2") or 4 (7/16") nozzles would yield the maximum Harris efficiency.

Lots of potential hydro power in my creek today  

Bob B.

[mike90045]

In a circuit, AMPS have to be the same.  Something else is wrong.  I'd expect the voltage drop.

The Iota has a .6 power factor, so combine that with the 80% eff, and you are not going to get it's full output with a hydro generator.   

You could  feed the TS PWM controller with one OR the other, but it is PWM, and not MPPT and will not downconvert spare voltage to amps.  You need MPPT to do that.

Panels, if connected without a blocking diode, will suck power from the batteries at night, draw varys on type of panels. Use a blocking diode rated for your full array power at about 100VDC.
( for $8 bucks, this should work  http://search.digikey.com/scripts/dksearch/dksus.dll?Detail&name=APT100S20BG-ND  )

I don't know if you can program the MS TS PWM into DIVERSION mode,
connect Solar and Hydro to the batteries, and when you hit diversion voltage, the MA TS dumps the excess into your load bank.  (say about 11 - 3pm daily, if the sun is out and charging, and the hydro is going too.)

[Jedon]

Bob, wow thanks for all the info! The 19psi is static, from GPS and Google Earth I though I had about 100' of drop but it turned out to be half that. Due to some fun with the pipes I don't have the pressure gauge on it at the moment.
If I should only be making 200W after all is said and done, perhaps it's all working like it should be and I just have over inflated ideas of how much power I should be getting due to going off the raw output of the hydro.
I noticed that now that I am running 4 1/2 nozzles that some air is getting into the pipe, my intake is a 3" pipe through a damn and even though there is water above the damn it doesn't seem to be letting quite enough through to keep the intake pipe fed. I guess I'll put one one of the smaller nozzles back on.
I fiddled with it some more and this time was more scientific about it, here are my results:
Full Field:
At the power shed ( 750ft from the turbine ) voltage was 109V to the charger and the batteries were are 50.1. Later when the sun was on the 800W of PV the battery voltage went up to 53V and the hydro voltage went up to 114.4V so there is a correlation between the voltage of the batteries and the loaded hydro voltage.
I went down the the turbine and measured 108.8V when the voltage at the shed was 109.2V, I then shut it off and connected my multimeter to read current and got 8.4A which then fluctuated a bit and even went down to 5.2A when some air was in the pipe.
To test the water pressure I then measured with nozzles off:
1 nozzle  1.5A @ 107.7V
2 nozzles 3.1A @ 109.4V
3 nozzles 4.6A @ 109.6V
4 nozzles 8.4A @ 108.8V
I noticed that there was more load on the unit with my meter than with the IOTA alone, it spins slower when I measure amps than when I measure volts.
I then started playing with the field strength:

1/8th turn off full field:
1 nozzle  1.5A @ 109.3V
2 nozzles 2.7A @ 111.8V
3 nozzles 3.9A @ 113.3V
4 nozzles 4.8A @ 113.8V

1/4 turn off full:
1 nozzle  1.5A @ 108.7V
2 nozzles 3.0A @ 111.2V
3 nozzles 3.8A @ 112.7V
4 nozzles 4.5A @ 112.8V

3/8 turn off of full:
1 nozzle  2.8A @ 106.9V
2 nozzles 5.8A @ 105.8V
3 nozzles 5.8A @ 106.5V
4 nozzles 5.8A @ 103.4V

1/2 turn off full field
1 nozzle  3.7A @ 79.6V
2 nozzles 3.8A @ 77.7V
3 nozzles 3.8A @ 77.7V
4 nozzles 3.8A @ 77.7V

I left it at 1/8th off of full then took readings for a while, the voltage slowly dropped down to 110.3V.
Back at the power shed it was 108.8. A bit later when the batteries got up to 52.2 from the solar it was 112.8, then 114.4 @ 53.3V.

Mike,
I tried connecting the hydro right to the batteries and it drops the hydro voltage down to match the batteries, it didn't seem to make much power like that but I don't really have any way to measure it besides seeing what the battery voltage is in the morning.

I can set the TS-60 to diversion mode but I've never come close to needing a dump load so far.

Right now the hydro alternator is set for high voltage wye, I could wire it into delta and try hooking it directly to the batteries like that? Perhaps line losses at the lower voltage would be offset by the inefficiencies of the charger?

[rl71459]

This is a great thread!  Very interesting.... I have little knowledge of hydro systems. This is great!

So is the amount of head available the limiting factor? or is it the hydro system? both?

Rob

[sailawayrb]

Hi Jedon,

Glad I could be of some help.

OK, if your 19 PSI is indeed "static pressure", than the elevation difference between your pipe intake and your Harris location (which is also your maximum available "gross head")  is exactly 44 feet (i.e., 19 PSI divided by 0.433 PSI per foot).  

Now we need to calculate your pipe head loss due to the pipe friction in your 400 feet run of 3" PVC pipe so we can determine the "net head" available at your Harris location:

At 50 GPM, there is 0.65 feet of head loss for every 100 feet of 3" PVC pipe.  So, at 50 GPM, you will lose about 2.6 feet of head (i.e., 4 times 0.65).  So the "net head" available at your Harris location is about 41 feet if your flow rate is 50 GPM.

At 100 GPM, there is 2.33 feet of head loss for every 100 feet of 3" PVC pipe.  So, at 100 GPM, you will lose about 9.3 feet of head (i.e., 4 times 2.33).  So the "net head" available at your Harris location is about 35 feet if your flow rate is 100 GPM.

At 150 GPM, there is 4.93 feet of head loss for every 100 feet of 3" PVC pipe.  So, at 150 GPM, you will lose about 19.7 feet of head (i.e., 4 times 4.93).  So the "net head" available at your Harris location is about 24 feet if your flow rate is 150 GPM.

With 400 feet of 3" PVC pipe, a drop of 44 feet, a PVC roughness coefficient of 130, and applying the Hazen-Williams equation, your "net head" will go to zero at about 200 GPM.

http://www.calctool.org/CALC/eng/civil/hazen-williams_g

Lets say you elected to use 6" in lieu of 3" PVC pipe.  At 150 GPM, there is 0.2 feet of head loss for every 100 feet of 6" PVC pipe.  So, at 150 GPM, you will lose about 0.8 feet of head (i.e., 4 times 0.2).  So the "net head" available at your Harris location is about 43 feet if your flow rate is 150 GPM.

The fundamental hydropower "rule of thumb" (which assumes a 53% overall efficiency to get the magic "10") is:

Power (in Watts) equals Net Head (in Feet) times Flow Rate (in GPM), all divided by 10

At 50 GPM and 41 feet of "net head", we would expect about 205 Watts.

At 100 GPM and 35 feet of "net head", we would expect about 350 Watts.  

At 150 GPM and 24 feet of "net head", we would expect 360 Watts.

If you used 6" PVC pipe, at 150 GPM and 43 feet of "net head", we would expect 645 Watts.

I think this illustrates how pipe size and flow rate can significantly  influence "net head" (and "dynamic pressure") and ultimately your available power...and why it would be very worthwhile to know the maximum pipe flow rate (or the "dynamic pressure").  I would guess your actual power to be between 205 and 360 Watts.  This is also consistent with the previous 19 PSI static pressure NoOutage calculation of 253 Watts.

Arguably, multiplying your voltage and current measurement, should get the job done too.  If we use your 1/8 turn, 4 nozzle configuration and multiply 4.8A times 113.8V, we get 546 Watts.  There appears about 46% power calculation discrepancy between using your measured voltage/current versus using your measured static head and likely flow rate given your pipe configuration.  I am very curious how this can be?

How confident are you about your pressure and current measurements?  Any chance you can measure the pipe flow rate (see McMaster-Carr water flow meter for PVC pipe, P/N 4349K4)?  Here's another way:

http://smallhydro.com/200910/small-micro-hydro/measuring-the-flow-rate-q-from-an-openpipe/  

BTW and unlike "static pressure" (which needs to be measured at your Harris location), it really doesn't matter where you measure the flow rate (or "dynamic pressure") along the length of pipe.  Flow rate and "dynamic pressure" don't change along the pipe length (unlike "static pressure" and ultimately "net head", which do change along the length of pipe).

Bob B.

[sailawayrb]

In a circuit, AMPS have to be the same.  Something else is wrong.  

Precisely!  In a pipe with relatively incompressible fluid like water, flow rate (GPM) has to be the same too.  In fact, flow rate in pipe is analogous to current in an electrical circuit...and pressure in pipe is analogous to voltage in an electrical circuit.  I suspect inaccurate current (Amps) measurement is the likely culprit.

Bob B.

[sailawayrb]

So is the amount of head available the limiting factor? or is it the hydro system? both?

Rob

Available "gross head" (which is essentially the elevation change of stream across your property) and available stream flow rate are the ultimate limiting factors in terms of how much hydro power one can generate.  Then economics come into play...size and length of pipe you can install (which influences the "net head" your turbine will see)...and size of turbine/generator you can install...

Bob B.

[mbryner]

Bob B.

Great pic of Evans Creek!   And thanks for the link to nooutage.com.   Great site.   

[Jedon]

Here is something that could be an issue, I don't measure the current and voltage at the same time, measure the voltage then shut the unit down, switch to current measuring and turn it back on. So in the case where I am measuring voltage the unit is loaded down by the IOTA but when I measure current it's loaded by both the DMM and the IOTA, could this make a significant difference? I do notice that the unit has more load on it when I measure current with the DMM than when it's loaded only by the IOTA.

I would guess I'm closer to 150gpm than to 80, the 3" pipe was a compromise between high winter flow rates and much lower summer flow rates, I was afraid that if I was only putting 30gpm into the pipe in the summer that a 4" would get air in it but I guess that's not really right since I restrict the flow with the nozzles. Cost and weight of the pipes was a more significant issue. Plus I really thought I was going to have 100' of head instead of less than 50.

When I got up this morning my battery voltage was at 49.4V whereas before I switched out a 3/8 nozzle for a 1/2 and lowered the field strength a little the voltage in the morning was more like 50.1 to 50.5 so I have managed to make things worse instead of better.