You know what Marion? I’m happy for that seredipity! I just now came across the perfect series about water wheels for me. It’s aimed at children, so it’s perfectly aligned with my level 
I actually enjoy these vids alot, he makes many great projects involving electronics, mechanics and playing. Highly recommended! I might very well end up with a pelton wheel, not the traditional one.
And now he has thaugth about what an alternator and rectifier is - with a balloon!
This could probably work with that water wheel linked above.
Water wheel converts high volume low pressure into low volume high pressure. Then nozzle converts low velocity high pressure into high velocity. Then Pelton wheel.
Although I’m not sure if it’s different/better than harnessing the torque of the first water wheel directly with a belt to boost the rpm to a generator.
I’m not sure if I fully understand? Are you suggesting that I make two wheels to lift water up and gain higher pressure?
The thing is- I have to make everything as low profile as possible. I can’t have kids climbing all over it…
This YouTube guy has inspired me to consider the Pelton option, instead of the backshot type. With a Pelton setup, I can run longer pvc pipes on the bottom of the stream, even hidden under the rocks. At a desired point, I can use a nozzle and go for higher rpm, not needing such a big housing.
If you have a high enough height difference between the inlet and outlet then it’s not necessary but if you have a low elevation drop and lots of water then you would need something to boost the pressure for a Pelton wheel to work.
Can you take a picture of your creek?
First thing in the morning! 
Here is the creek:
I think I can get 2-3 meters of fall if I use long and flexible pipes. My initial plan was building an aquaduct out of wood, but I’ve scrapped that. Laying flexible pipes on the bottom of the stream bed would hide the installation much better, and if I did it properly, I could even leave them there for the winter, and only rescue the turbine.
It’s been said many times, but that’s a beautiful place to live.
I think your pipe idea is a good one. As long as the pipe is not too narrow, you should get reasonable pressure and volume. Start with a simple nozzle and simple impulse turbine and upgrade as you feel like it.
I was thinking I could actually get several pipes. If I spread them across the width of the stream, and joined them at one point, they would give a decent preassure - without being too intrusive in the terrain.
Really nice place, I wish I lived somewhere like that.
It seems like you don’t have a lot of height but a decent amount of flow. So, in my opinion, the Pelton style turbines with the nozzle are probably out of the question, I’m no expert but I’m fairly sure that what you need for these is high velocity, coming from high pressure, which comes from height. I wouldn’t try that under at least 10 meters height or more.
Here you have low speed but a decent quantity of water, so I’d be looking at making a small dam, then either a gravitational vortex turbine, or a more classic waterwheel.
The waterwheel is probably the easiest to build and the most likely to work so I’d say stick with it. The dam ensures that you get all the water passing through the waterwheel, this way you have less height but all the flow the river provides, hence it is likely to make decent power.
Thanks Dui!
The thing is - I want to make this thing as little obtrusive as possible. The river is right in the middle of a neighborhood, and I can’t have to muncipality-people coming over and giving me trouble… A pelton-setup would be easier to make compact and “hideable”.
Another option that I was considering intitally (but quickly gave up because of low efficiency) is some kind of water screw setup. Such a turbine can be made quite long, and not as noticeable. Unfortunately, I’m not sure if it’ll be efficient at all…
Make it decorative. It’s not uncommon to see “fake” water wheels over here, with a hidden pump recirculating the water. In your case, no pump needed. Power a few decorative LED yard lights to satisfy those who may ask a few more questions, without revealing the actual generating capacity of your system.
Actually not a bad idea! The wooden wheel I made would be both decorative, but have plenty of spinning force. It’s only that I’m afraid of the kids in the neighborhood, who’ll definately stick their arms into any place intriguing enough… hum hum… I’m going to check with a plumber friend about different types of piping to lay down. We’ll see
I wonder if I put 2-3-4 lengths of 10-15 meter of these pipes dug into the stream floor, and joined them - that would give me a quite decent amount of water. Not sure about the pressure, but the amount of water should be decent - it has to be seen what I could make with a nozzle.
The cheapest tubes would be cable tubes. Unfortunately, they are always corrugated. What do you think, would it slow the flow too much?
While I do understand your concerns about neighbors, city and other annoying people, I don’t want to discourage you but it’s very likely you won’t go anywhere with those tubes. 2 or 3 meters max with this kind of flow will give you miserable results. I’d say don’t expect more than 5 watts. Also this kind of tube isn’t smooth, so you get lots of internal friction from the water, evellowering its efficiency.
It’ll be disappointing especially given the costs you’ll have invested into tubes, turbine, your time and whatnot.
The idea of making a nice looking “decorative” wheel is nice and sneaky, I love it.
Or the other way, making it dirt cheap, like a proof of concept, install it for a few months, see if any annoying dude shows up. If not, make it look better and more durable. Maybe you live in a nice city with decent neighbors, who knows.
Build a dam out of sticks and clay, blame it on beavers if someone complains …
Now joking aside, there are several companies that sell so called hydrokinetic turbines (or just river turbines) that can be dropped into a stream and will be completely submerged. These are more useful in fast flowing deep rivers though so this idea is unlikely to work. Google did not find a DIY version so it’s probably not that easy to make either.
An interessting video of a tech which might apply very well in your case. Plus it’s probably easy to build if you own a 3D printer (or if you are a bit creative, there are other ways too.
They don’t really say how much power this thing can output. M y guess is that it is quite low since there’s no free lunch here and everything depends on flow x height, but at least it’s portable, you can build several of these and it might be a fun experiment.
I think also that the technique of using sand bags for making a small temporary dam for cheap is quite simple yet very clever.
One thing to check on… In Texas you’re not allowed to dam any type of flowing water without approval. No matter how small the dam.
Well I guess that’s why you don’t have beavers there. Your loss.
