Hydroelectric Generator

3D Printed Hydroelectric Generator

Download, print and build your own hydro electric generator right here. Use it to light up a bank of LEDs with diode rectifiers and a Zener diode voltmeter, or just one LED if you are light on electronics!

Safety

This project combines electricity and water. Be safe and keep them separate at all times. Use the splash proof enclosure for the electronics, keep towels handy and clean up any spills, and don’t allow the stepper motor to get flooded. Allow all parts to dry fully before rerunning.

A hobby knife or blade is occasionally required to clean up the 3D printed parts or cut into plastic. Be knife safe and don’t rush.

When drilling, go slowly, wear eye protection and gloves. Ensure you clamp all parts before drilling.

Parts and Tools List

Hardware

Tailwater (a bucket)
- For supporting the generator and catching the used water
- Can be round or straight sided
Reservoir (another bucket)
- Holds the water before it gets to the generator
- Square sides recommended so it fits nicely with Part 8 – High-Flow Tap
3D printed turbine housing
3D printed Pelton Wheel turbine rotor
3D printed turbine housing supports
Fasteners
- 2x 3mm bolts, or equivalent
- 2x 2mm bolts + washers + nuts, or equivalent
(Optional) 3D printed hose splitter
High flow water tank tap
- This one has a 12mm (1/2″) hose barb, but a normal hose fitting is fine
(Optional) Funnel
- Can be used as an alternative to the tap and bucket for the reservoir
Clear plastic
- These are to cover the front and back of the turbine housing
- Takeaway plastic food container lids work well
Garden hose
- Normal 12mm (1/2″) garden hose
- At least 2m (6.5ft) long
Towels! (not shown)

Electronics

8x Diodes
- Standard 1A diodes are fine e.g. 1N4004
4x Resistors
- 470ohm, 1W
4x Red LEDs
Breadboard
(Optional) Terminal block with 4 ports
Breadboard jumper wire
Mix of Zener diodes, e.g. I used
- 5.1V 1N4733
- 4.7V 1N4732
- 3.9V 1N4730
- 3.3V 1N4728
- (More on how this works later)
Stepper motor
- 12V, 48 pole hobby stepper motor with 5 wires
- You can use this one from Jaycar or this one from Sparkfun
Capacitor
- 16V, 470uF
Wire
Housing (to keep it all dry!)

Alternative B: If you don’t have Zener diodes, you can leave them out and use Circuit B instead, detailed below.

Alternative C: If you just have LEDs and resistors, use Circuit C!

Tackle Engines head-on, all in less than 2-hours on Udemy!

Be confident in the concept, configurations, and improvements of engines, from diesel all the way up to hybrids and electric vehicles.

Click here for the course!

Tools

Drill
Blade
- For cleanup of 3D printed parts
Epoxy glue
(Optional) Deburring tool
- Handy for cleanup of 3D printed parts
Spade bit
- Sized to match the hole needed for your tap
- Alternatively, you can cut the hole with a blade
Needle-nose pliers
- For cleanup of 3D printed parts
Tape measure

Instructions

1. Printing the Turbine and Housing

Download the .stl files and print in your preferred 3D printer. I used an Ultimaker Original printer, so all duration guides and settings are based on this. Some suggested settings are:

PLA works fine as a medium
The turbine housing works well with a layer height of up to 0.2mm
For the turbine itself, use 0.15mm layer height
Wall thickness: 0.8mm
Infill density: 20%
Generate support, but try to only use it when the print is ‘touching the buildplate’. It’s fine if this is not possible, you will just need to spend some extra time removing support from inside the nozzles and other areas

Print:

One housing
- Approx. 5 hrs to print at the above settings
- Allow 1 hr for cleanup and assembly
One turbine rotor
- Approx. 3.5 hrs to print at the above settings
- Allow 1 hr for cleanup
Two bucket clips
- Approx. 1 hr to print both
As many hose splitters as you want
- Approx. 45 min to print each

Cleanup:

Remove all build support material with needle nose pliers and a blade paying particular care to ensure
1. The internals of the nozzles are clear and smooth
2. The back of the housing is smooth
3. The cups of the turbine rotor are smooth and without obstruction
You may need to use the drill to make sure the different sets of holes are big enough, but you can test this at the assembly stage

2. Assemble the turbine and housing

Cut two pieces of the plastic to create the front and back housing covers. Go slow, clear plastic containers are usually brittle and may crack easily.

At the end, the removable front cover will just slide in from the top and fold under the top clips. The rear cover must be glued in place now with epoxy adhesive, or similar.

Front Cover

Back Cover

Use the 2mm bolts to affix the stepper motor to the back of the housing, using the mounting holes. The bolt heads should be inside the housing and the nuts outside, so they don’t obstruct the rotor.

Push the rotor onto the stepper motor shaft and give it a spin to make sure it’s not grinding on anything. A little resistance from the magnets inside the stepper motor is normal. Make sure the open side of the cups faces the nozzle outlets. You can slide the front cover on now.

Use 3mm bolts to connect the bucket clips to the housing tabs near the base. They probably won’t need bolts and go straight into the plastic. You can add bolts if the plastic is too loose.

3. Assemble the pipework

Drill a hole in the Reservoir bucket, using the spade bit. This should be on the front near the bottom, and the spade bit should match the size needed for the high flow tap. Go slow – too fast will melt the plastic.

If you don’t have a spade bit you can cut this hole (carefully) with a blade.

Insert the high flow tap into the bucket with the rubber seal on the outside and the nut on the inside. Make sure the tap is off (it helps to mark which way is on and off with a marker or tape), and test the bucket is water tight.

Insert the barb from the tap into one end of the hose. Put the other end of the hose onto one of the housing barbs.

Place the bucket onto a ladder or shelf (my clothes dryer works great!) about 1.5m to 1.8m up (5 or 6 feet). I recommend taping it down or affixing it in some other manner – you don’t want all that water coming down on top of you or your space.

The garden hose may be stiff, so you may need to tape or cable tie it to a few things to keep it steady.

Alternatively, you can replace the bucket and the tap with a funnel, and fill this from a jug (requires steady hands!).

Hook the housing onto the second bucket using the clips. Place the second bucket on the floor.

4. Assemble the electronics

The stepper motor wires need to be extended to allow easy placement of the electronics away from the water flow. You can do this in your own preferred method by:

Soldering longer wires onto the existing wires, and using heat shrink to cover the connection, OR
Tying the wires together, without solder, OR
Solder the wires into a 4-way plug for easy connect-ability

Whatever method you choose, consider this best practice wiring splicing guide that NASA uses.

The breadboard is housed in a splash-proof electronics enclosure to keep everything dry. Wires enter through a hold drilled into the bottom of the enclosure, so any splashes don’t run into the hole.

There are a few options when assembling the electronics:

Circuit A is the full circuit, requiring all the parts in the parts list. It allows for efficient use of the energy generated by using a rectifier circuit, and a voltmeter to show how much power you are generating.

Circuit B removes the voltmeter, and allows you to efficiently power a fixed number of LEDs with a rectifier circuit.

Circuit C does not have a voltmeter or a rectifier circuit, so allows you to inefficiently power a fixed number of LEDs. The circuit will be subject to LED flicker and won’t be able to power as many LEDs.

Here are the breadboard layouts and circuit diagrams.