need some advice on penstock sizing

[junglehydro]

Hya all, So I am trying to figure out how to build my penstock, and thought I would ask some help on advice what you would do in my situation.

Here's the plan; power a 5kw turbine from a jungle creek that runs year round.

So the situation is as follows: I have a creek nearby that has plenty of flow, I haven't measured but if I'd have to guess it would be upward of 50 liters a second easily. It flows through a dense jungle, with an average gradient of around 15-20%, some parts are pretty steep with a good waterfall, other parts are slow flowing and wider.

I tried posting a youtube link, but I get the "Sorry, you are not allowed to post external links." message...

So after some napkin calculations aided with the powerspout calculator I've come to two posibilities:

• I make a 600 meter penstock with 100m head of 75mm pipe and get about 3600 watts out of my turbine
• I make a 150/200 meter penstock with 50 meter head of 100mm pipe on one of the steeper parts and get about the full power out of my turbine

The first would require longer pipes through difficult terrain, the second might require more difficult construction of my basin and turbine in the middle of the jungle. Any thoughts are welcome!

And so do I understand it correctly that     head X flow = power? So with less head but a bigger pipe with more water I can achieve the same results at the turbine? and no different turbine design is required (other than bigger nozzles with bigger pipes obviously)?

[bigrockcandymountain]

You are correct that head x flow = power. Your estimates seem pretty reasonable for power output. 

I think i would do the 50m head and 100mm pipe, but 100mm is very easy to get here and quite cheap.  Even 150mm might be a good idea to price out.

Are you doing a pelton wheel?  It might take some nozzle tuning to get your generator tuned for specific hz at specific power.

 This is a very ambitious idea and a great hydro resource you have there.  Hopefully you can make it work. 

[SparWeb]

Lots of hydro potential there.
I think you are "supposed to" use a Pelton wheel for head over 30 meters.

Various pieces of information you'll be looking for:
- Pelton wheel sizing charts and suppliers
- Nozzle design figures (I have some here, but you can get specific recommendations from the supplier of the pelton, of course.)
- Debris separators

Not a recommendation, really, just happens to be handy: https://www.powerspout.com/
They say things on their website about shipping internationally - which may also help you.

[junglehydro]

I think you are "supposed to" use a Pelton wheel for head over 30 meters.

Yeah I'm going with a pelton for sure.

Pelton wheel sizing charts and suppliers

So I am going for a wheel with a pcd of around 200-250mm, based off of the charts in "Micro‑hydro Pelton Turbine Manual" by Jeremy Thake, and I haven't been able to find any suppliers with decent quality wheels, so I'm going to have it made in a local metal workshop instead.. (I live in a rural area in Colombia)

Nozzle design figures (I have some here, but you can get specific recommendations from the supplier of the pelton, of course.)

Could you share those with me? Since I don't have a supplier I was planning on starting with a small nozzle and just shaving it bigger and testing until I reach the desired result.

And for the debris separator I am planning to build a self cleaning intake system somehwat like this design:



And I have read through pretty much all info on the powerspout site, that site got me started on thinking about hydro actually :-) But I prefer to build one turbine with locally sourced parts instead of importing 3 powerspouts. both for costsavings but even more for ease of maintenance and replacing parts.

[SparWeb]

Oh, that's too bad that being in Columbia prevents you from importing powerspouts... or other stuff made in North America in general? 
Making it yourself is OK.  The spoons are a curious thing to be making yourself or trying to source locally.  How's that going?

The nozzle is an open question - I'm looking at that other question you asked earlier, about regulating voltage. Wouldn't that mean you are going to need a variable nozzle?  That would be hard to set up.  Perhaps you plan to regulate voltage using a diversion load.  That could be easier but still demands a lot of finesse.

Here's one thing I can give you:

[SparWeb]

And this

[junglehydro]

Here's one thing I can give you:

Wow, thanks so much! that chart is amazingly useful, I was planning on eyeballing and then trial and error to optimize, so this at the minimum saves me a lot of time!

Oh, that's too bad that being in Columbia prevents you from importing powerspouts... or other stuff made in North America in general? 
Making it yourself is OK.  The spoons are a curious thing to be making yourself or trying to source locally.  How's that going?

Well it doesn't prevent me, but I was just thinking about doing it like this since this will make fixing things a lot faster if stuff breaks, and my business in the future will depend on it, so can't really be waiting weeks for new parts in case something happens. And a lot of deliveries get "lost" in the mail here, so the less expensive stuff I need to fly in the better.

So the spoons seem to be going ok, after some searching found a great 3d model based on the design in the book of Jeremy Thake. So I am having that printed and then cast in aluminium. And how do you mean curious, I was having a hard time finding them online at the right size, and this for sure is faster. Am waiting on the princing to find out if its also cheaper :-)

The nozzle is an open question - I'm looking at that other question you asked earlier, about regulating voltage. Wouldn't that mean you are going to need a variable nozzle?  That would be hard to set up.  Perhaps you plan to regulate voltage using a diversion load.  That could be easier but still demands a lot of finesse.

Yeah I have another topic in the controls section of the forum  I am working with someone who knows about programming microcontrollers and such, and he is helping me attempt to build a load controller with 5kw diversion load.

[SparWeb]

You have found a foundry to cast them - perfect!

[Vortechs]

That sounds like a cool project.

I got spoons from this guy in Italy: https://www.flickr.com/photos/peltonturgo/15319820120/
They're really well made and reasonably priced. Easy enough to make up your own wheel with them. Originally I got one of the new ones from Powerspout but it was expensive flimsy crap.

[junglehydro]

That sounds like a cool project.

I got spoons from this guy in Italy:
They're really well made and reasonably priced. Easy enough to make up your own wheel with them. Originally I got one of the new ones from Powerspout but it was expensive flimsy crap.

Thanks! I would love to post some pictures of the progress, but I currently have nowhere to host them. I used photobucket in the past but they seem to be pretty dead..

They look good indeed, although I prefer to have mine in aluminum.

[SparWeb]

Upload them here!
While posting, click the + attachments.

It does help a lot if you trim and resize before you try to post, of course - a good general rule for all cases, of course.

[junglehydro]

Alright, so my first attempt at a picture. This is the stream that I'll be using for our turbine:

[SparWeb]

Great spot!

[junglehydro]

Thanks! Yeah it's an amazing place and I have also just started offering tours to the place. some pretty spectacular hiking with a nice swim at the end.

So a question for senior members/admins, I thought I would just document my entire project on this forum so it can possibly help others in the future doing a similar project, including sharing 3d models I make, parts lists and programming of controllers and such. Should I open a new topic for that or just continue in this one? To help with findability for future google searches and such.

[DamonHD]

I would suggest opening a new topic, and trying to stay roughly on topic in there (we'll drift a bit that's fine)...

Rgds

Damon

[SparWeb]

Yes, we can always work with you as you post about your projects, big and small.
In many ways, the subjects you post are entirely up to you. 
If you do want to consider search and consistency of topic, then (first) that's great, and second, there's a variety of ways to do it that will make sense on this forum.
Many projects have been documented here or still in the process, so feel free to see what they look like, choose what works best for you.

[Mary B]

Just a thought, start a topic in the pit called *myname* pictures and add to it as you get new ones.

[junglehydro]

Here's one thing I can give you:

Never got that file to work for me, is it just me or is it perhaps corrupt? could you try uploading it again or could it be sent directly somehow?

[SparWeb]

Here's a fresh copy, but from my point of view the file identical:

 Goulds_Pumps_Tech_Data.pdf (452.17 kB - downloaded 467 times.)

[junglehydro]

this one works, thanks!