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Mike 604

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Looking to get some insight and learn from others regarding Micro Hydro.
For the last four weekends have been busy installing a 6" penstock pipe of 140 ft of length.
The Micro Hydro that I have installed is made by Scotty Micro Hydro which is a crossflow turbine. It's capable of providing 1500-2000W of power via 3 phase output.
So my question is which set of electronics should I use to provide power to charge the batteries and be able to use the excess for a dump load
using hot water immersion heaters that I will install in my hot water tanks. My tanks have six inputs for heating so I want to use two electric
immersion heaters. My tanks are 1000 L each.
Next year I will get the PV installed so this will join my off grid setup.
Morning Star and Mid Nite solar make units, not cheap but which one to get or what else would you recommend please.
 

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Looking to get some insight and learn from others regarding Micro Hydro.
For the last four weekends have been busy installing a 6" penstock pipe of 140 ft of length.
The Micro Hydro that I have installed is made by Scotty Micro Hydro which is a crossflow turbine. It's capable of providing 1500-2000W of power via 3 phase output.
So my question is which set of electronics should I use to provide power to charge the batteries and be able to use the excess for a dump load
using hot water immersion heaters that I will install in my hot water tanks. My tanks have six inputs for heating so I want to use two electric
immersion heaters. My tanks are 1000 L each.
Next year I will get the PV installed so this will join my off grid setup.
Morning Star and Mid Nite solar make units, not cheap but which one to get or what else would you recommend please.
I would go with the Midnite classic. It seems to be the go-to for micro-hydro set-ups.
Warning: There are some models out there that don't have the aux outputs..... these won't work well for diversion load.

BTW: Even at the low end, that system is going to produce a lot of energy: 1500Wx24Hr/Day=36,000Wh/day.
Do you have a plan for the dump load if the tanks reach max temp?
 
The tanks will be used to bring temp to heat the house, using radiant/hydronic heating for my house which is in the concrete floors.
Once this has reached set temp will divert to green house and outdoor electric baseboard heater.
Can I use the 3 phase AC power to go to supplied by the MicroHydro manufactuer rectifier to go straight to the Midnite Classic 250 ?
Or do I have to use the Midnite Clipper to go to the Classic 250 ?
Thanks Filter Guy for your reply.
 
This says for both wind and hydro.
Probably best to confirm with Midnight if you want to go without; based on performance of your hydro generator they may be able to give advice. Don't want to blow out the Midnight Classic.


Manual indicates the AUX relay of Midnight Classic controls Clipper.


Somehow, you have to make sure voltage never exceeds input specs of charge controller. Wind turbines always need to be limited, because wind speed varies. Do you know what open-circuit voltage of your hydro turbine is?

Can your turbine tolerate operating no-load? It would spin faster, and this probably depends on how much head your water source has.


For comparison, here's a similar protection device that SMA used to offer (They've since stopped selling inverters configured for turbines.)
The inverter manual mentions both wind and hydro, but protection box manual only mentions wind.


 
The tanks will be used to bring temp to heat the house, using radiant/hydronic heating for my house which is in the concrete floors.
Once this has reached set temp will divert to green house and outdoor electric baseboard heater.
Can I use the 3 phase AC power to go to supplied by the MicroHydro manufactuer rectifier to go straight to the Midnite Classic 250 ?
Or do I have to use the Midnite Clipper to go to the Classic 250 ?
Thanks Filter Guy for your reply.
Yes, it does have to be rectified before it goes to the Midnight.
 
This says for both wind and hydro.
Probably best to confirm with Midnight if you want to go without; based on performance of your hydro generator they may be able to give advice. Don't want to blow out the Midnight Classic.


Manual indicates the AUX relay of Midnight Classic controls Clipper.



The Classic aux control can be programmed for a few different modes. The simplest mode is simply that it turns on when the voltage gets high. This can be used to turn on the dump load and thereby control the voltage. This type of setup has been used on many installations.

The more elegant mode is to program the Aux control to put out a PWM signal that can be used to gradually increase the load as the voltage goes up. The clipper can use this signal to control the dump load....but the dump load is built into the clipper. In the OP's case, the ideal scenario would be to have a clipper-like device that allows an external dump load.

1633545721410.png


Do you know what open-circuit voltage of your hydro turbine is?
In my experience, open-circuit voltage is rather nebulas on turbines because it depends so much on the pressure and flow of the water. Some turbine manufacturers do a better job than others documenting it but even then it is difficult to match the spec to the specific conditions of a particular install. For the most part, it should be assumed the voltage will be too high and a dump load is needed to control it.

Can your turbine tolerate operating no-load? It would spin faster, and this probably depends on how much head your water source has.
Some turbine manufacturers say their turbine can free-wheel (Operate without a load), but they will also warn you it is hard on the bearings. Other turbine manufacturers will explicitly state free-wheeling will damage the turbine. In general, the larger the diameter of the turbine, the higher the forces on the blades and the less likely it will be able to handle free-wheeling.
 
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Looking to get some insight and learn from others regarding Micro Hydro.
For the last four weekends have been busy installing a 6" penstock pipe of 140 ft of length.
The Micro Hydro that I have installed is made by Scotty Micro Hydro which is a crossflow turbine. It's capable of providing 1500-2000W of power via 3 phase output.
So my question is which set of electronics should I use to provide power to charge the batteries and be able to use the excess for a dump load
using hot water immersion heaters that I will install in my hot water tanks. My tanks have six inputs for heating so I want to use two electric
immersion heaters. My tanks are 1000 L each.
Next year I will get the PV installed so this will join my off grid setup.
Morning Star and Mid Nite solar make units, not cheap but which one to get or what else would you recommend please.

Just out of curiosity, what is your gross head and flow expectation at your site? With a 6” penstock, I’m guessing higher than 20’ gross since to make 1500 W you’d need 900gpm and a 6” pipe with that flow would cost you about 3’ of net head due to friction losses over 140’ ….

I’m hydro powered with 8’ of net head at 4 CFS (1800gpm) through a 10” Francis turbine - about 1250 watts water to wire.
 
Water velocity from nozzle will be equal to or less than velocity you get by dropping a mass from a height equal to the head.
In the case of a Pelton wheel, max power has the buckets traveling half the velocity of the water (water turns direction to go back the way it came, and comes off the wheel with zero velocity relative to ground.)
No-load, Pelton wheel buckets would have same velocity as water.
So I would expect them to tolerate running no-load if head is not too high. Voltage should be proportional to no-load RPM.

Other style turbines could have different relationship between blade velocity and water speed.

It would be annoying to spend $1500+ on a resistor to heat the air.
Controlled by Classic - I presume a signal to enable? So if it fails open, the protection is lost? I would rather clipper clips unless a signal tells it not to; maybe they did that.
I could envision opening a valve to allow bypass of water as another way to reduce speed/output.
 
Water velocity from nozzle will be equal to or less than velocity you get by dropping a mass from a height equal to the head.
In the case of a Pelton wheel, max power has the buckets traveling half the velocity of the water (water turns direction to go back the way it came, and comes off the wheel with zero velocity relative to ground.)
No-load, Pelton wheel buckets would have same velocity as water.
So I would expect them to tolerate running no-load if head is not too high. Voltage should be proportional to no-load RPM.

Other style turbines could have different relationship between blade velocity and water speed.

It would be annoying to spend $1500+ on a resistor to heat the air.
Controlled by Classic - I presume a signal to enable? So if it fails open, the protection is lost? I would rather clipper clips unless a signal tells it not to; maybe they did that.
I could envision opening a valve to allow bypass of water as another way to reduce speed/output.
Dan New once fabbed a short threaded steel pipe section that was side drilled and tapped so he could screw in a few cheap 2kW water heater elements as needed - that little section of pipe was mounted in line with the penstock right before his needle valve and primary jet. The excess power heated the flowing water by not much before it hit the runner … I think it cost about $25 in parts ?
 
Thank you for all of the info, have to process all and continue to get the install finished.
Today I played hookey and went to the Island to get the pipe work installation finished and get the weir installed.
Beautiful sunny day to work.
Did get a chance to use my builders level to see what my head is.
Outlet of weir to the inlet of Scott Microhydro is 45' 4".
Length of pipe installation is 167'. We used 3 x22s and one 11.5 elbows.
Haven't had a chance to check the volume of water yet but a guess would be 10 to 15 gallons a minute.
It has just rained 4 times since the dry spell that we had from mid June to Oct.
Next trip will be to install the teck cable from turbine to the house.
We installed a 4" sleeve back in 2017 from the crawl space to the outside of the house
and installed a #2 gauge teck cable.
Now to get the rest of the gear to have power inside of the house, a long time coming.
Pic of the home made weir.
 

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Only 15 gpm? and 45' of head?

Using an equation from this link, I get 48W.
That's a far cry from 1500W. Maybe 1160 Wh/day.

Hope you've got a lot more water than that. Winter flow?
You wouldn't be using 6" pipe for 15 gpm.

 
Thank you for all of the info, have to process all and continue to get the install finished.
Today I played hookey and went to the Island to get the pipe work installation finished and get the weir installed.
Beautiful sunny day to work.
Did get a chance to use my builders level to see what my head is.
Outlet of weir to the inlet of Scott Microhydro is 45' 4".
Length of pipe installation is 167'. We used 3 x22s and one 11.5 elbows.
Haven't had a chance to check the volume of water yet but a guess would be 10 to 15 gallons a minute.
It has just rained 4 times since the dry spell that we had from mid June to Oct.
Next trip will be to install the teck cable from turbine to the house.
We installed a 4" sleeve back in 2017 from the crawl space to the outside of the house
and installed a #2 gauge teck cable.
Now to get the rest of the gear to have power inside of the house, a long time coming.
Pic of the home made weir.
Ok, a quick formula to estimate hydro power with a Typical 60% total water to wire efficiency factor -,which is really typical - is head in feet times flow in GPM divided by 12 = power in watts.

Head in feet x Flow in GPM / 12 = power in Watts

I truly hope you have more than 12 GPM. That’s a garden hose. It won’t spin the runner.
 
Ok, a quick formula to estimate hydro power with a Typical 60% total water to wire efficiency factor -,which is really typical - is head in feet times flow in GPM divided by 12 = power in watts.

Head in feet x Flow in GPM / 12 = power in Watts

I truly hope you have more than 12 GPM. That’s a garden hose. It won’t spin the runner. 45’ head x 12 GPM / 12 = 45 Watts. 45’ of head = 19.5 PSI - barely run a rain bird lawn sprinkler.

To get 1500 Watts at 45’ of head you’ll need 400 GPM. Just shy of 1CFS. (450 GPM). 45x400/12..= 1500 W
 
Yup, that was pretty dumb on my part, meant to write per second as per minute would be pretty bad.
Will read the info to the posted links after work, thanks for providing them. Always learning.
The Scotty MicroHydro uses a crossflow turbine. If you go his web site it explains it better than I can.
Have reached out to a user and it produces considerable more power than the nozzle types that he used previously.
I see many different types of nozzle MH being used on YouTube.
Came across a link after looking for how to create a dump load and whether I should ground the Scotty.
Link didn't answer my question but happy to see that the Scotty did well.
Will need to get the water from the 48" culvert to the weir so we can start to test.
This will be 5 to 6 feet long and will need to make something out of plywood and lumber to get it the weir up
and running. Can see what works best and once the creek slows down next year then get something made to be more permanent.
Need to purchase the charge controller but will contact MidNite to see their recommendations.
Thanks for the reaction to my post which got me to re read my error on the post.

 
The midnight classic has a few parameters for hydro, including speed of MPPT sweep and how far from maximum power it will search.


The link I found earlier with hydro power output assumed 0.4 efficiency. That might be valid if generator went to a diversion regulator (feeds battery voltage directly), but with MPPT there is voltage conversion and load is adjusted to find RPM where maximum power is generated. Should be much higher efficiency.

Manual also says,

"DANGER OF DEATH TO YOUR CLASSIC! When the Classic is used with wind or hydro, a Clipper-type device will most likely be needed to protect against over-voltage. A battery-based diversion load WILL NOT keep the Classic safe from over-voltage. High input voltage is recorded and over-voltage is not covered under warranty."
 
Update.
Well almost a month later and we have had several significant rain fall events.
We typically get close to 8 feet of rain a year, 2 weeks ago we had 297mm in 24hr period.
Back in Oct we installed the weir and balance of 6" pipe. Weir filled and pipe was full in seconds with the excess water flowing over the weir. The temporary water diversion from the culvert was made with 2x4s and some 1/4' plywood. At a later date this will be used as a template so I can get this bent up out of some ss. Aluminum beams will be used to support span the 6 feet to the culvert. The first pic is of the plywood, 2x4 set up to test the weir.
Weir filled in about 2 seconds and pipe was full.

Ran the teck cable to the MicroHydro station into a waterproof connection box. Started to rain like crazy so had to close up and will have to finish next weekend.

Inside of the house's crawl space I have connected the Teck cable to a 3 phase breaker box which also houses the dc rectifier.
For the in term I bought a Trace 2012 RV inverter from a Craigslist for $75 CDN. Bought a Midnite 250 charge controller which has an aux for the diversion load / dump load. Have ordered two dc powered hot water immersion element. My water tank is 2000L and has six ports for inputs so this shouldn't take to long to heat up to use for our hydronic heating system. But once the set temp has been reached will need to divert to an outside heater for now. Green house later?
This will be temporary to just get me through the winter and to see how this will work. We are at the house only on weekends winds allowing our safe passage. Have to work during the week....... but can see the light at the end of the tunnel.

Trying to make a final decisions on my full time set up, tesla batteries, inverter etc.
Will post some questions on the beginners section.
 

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