At Fuelternatives we are trying to help consumers find solutions to allow them to use alternative energy sources. We have been working on some experiments to that end and this is one of them...
In an effort to extend the offerings here, I thought it would be neat to include the basics for a hydro electric set up using PVC/standard plumbing fixtures and easily made parts.
I made some interesting discoveries along the way and am sharing them...
I started by trying to make an inline energy take off with a pre-made propeller blade from a paint stirrer. While an interesting thought, I couldn't get any reasonable motion out of it - which reminded me of my physics that the max torque will come with the force applied furthest out radially.
Paddle Wheel Hydro Power.
First things first - physics reminds us that we can make energy only convert it and every conversion includes loss. Next that water pressure from gravity is directly related only to the height of the smooth column flow.
Design plan - knowing that we want a smooth flow but our goal is to move the water out to the radial extremes of our propeller, I created a basic test harness to try and understand how to optimize the hydro power system. The pipes here are really representative of what you would have to install in your environment. I fill up the 5 foot tall 2 inch pipe to get a know water volume for efficiency testing.
The picture below gives a good taste for the workings...
Step 1: Water Flow
The point here is to show the behavior of the water and the wheel. We are aiming the water jets to hit just under tangent to the edge of the wheel so we get maximum effect. Note the whit painted wheel section shows the spin.
A note on performance... You can see the short pipe on the far side is impacting the wheel well, but on the longer jet on the near side needs to be tweaked to maximize impact.
Step 2: Building the Structure
The support structure for your practice design is not critical. Shown here, I have a 2 by frame work with a peg board top and a support piece of plywood to keep the wheel in alignment.
The feed pipe gets filled from the hose while I hold the jets closed. Then step back cause water is splashing everywhere.
Ultimately, an installed system might get set in a sump style container so that it can drain away the water.
Step 3: The Plumbing
It is important to keep a full pipe since total "head" or falling distance is the basis of water pressure. If we introduce significant disruptions in flow we might impact performance...
We have a 2 inch feed line, but we want it to come out in a tight and aimed water jet. Given that we reduce from 2 to 1.5 inch "T" then plug the "T" ends with 1 inch reducers that then tie into 1 inch "90" bends and in this case, we have the other end of the 90 be a 1/2" compression fitting so that we can use 1/2" copper pipes as our jets.
Copper pipe is easily bent to shape and the tips flattened to maximize the impact on the paddle wheels.
At this point only the compression joint is tight both to the copper and the PVC so that all other angles and parts are just pressure fit, allowing me to change them as needed. To get the far side jet angled so close, it uses a 90 degree compression fitting that you can make out with effort in the back of the picture.