Water Turbine Generator

This project began as a daydream, where I thought, can a small water turbine create power for campers and backpackers while in the wilderness? At the moment, I have not completed full field testing because my motor’s wires were damaged during assembly, but I have learned a lot by attempting to build a physical prototype. Most importantly, making it is fun for those who want to build a water turbine. I hope you find this information to be a good starting point in your journey.

Note: I am a U.S. citizen and a junior in high school.

1. Gimbal Brushless Motor 90KV
2. 2 Conductor Electrical Wire
3. 12v to 5v Dc Converter Buck Module USB
4. AC 10-28V to DC 12V Power Module
5. Spring-Loaded Rotary Shaft Seal 3/4
6. PLA
7. 3d printer
8. Sordering Iron
9. 10-32 brass threaded inserts
10. M3-0.5 x 10mm long Flat head Bolts
11. 3/4 long 10-32 threaded rod or bolt
12. Heat shrink
13. Soder
14. Sand Paper
15. Drill
16. 1/8 inch paracored
17. Lighter
18. Auto Desk Inventor

These are the primary tools and supplies needed

When doing research, I found that there was a company called WaterLily Turbine that developed a similar product and used to sell it before they unfortunately went out of business. I mention this to acknowledge the fact that what I have made is different, but the general shape is inspired by the WaterLily. Unlike the WaterLily, I used a brushless motor that has a rotary shaft seal. Now that I have worked with the physical components, I recommend trying to embed magnets in the main body and copper windings along the circumference of the turbine blades. Then, add a low-friction bearing in the middle. This allows for the least amount of energy lost to friction and, in some ways, reduces complications because less waterproofing is needed. However, this greatly increases manufacturing challenges, as the copper windings must be fully enclosed in plastic, which may not be easy to do. If I were to redesign this, this is the approach I would take, as the rotary shaft seals add a lot of friction to the system.

When printing the turbine body, it is critical to have brim enabled, using a 10 mm interior and exterior brim. No supports are needed for the turbine body (25% infill, 3 walls).

The snap box needed no supports or brim (25% infill, 3 walls).

The turbine shaft required supports (25% infill, 4 walls).

The turbine prop v3 required normal supports (25% infill, 4 walls).

I printed everything out of PLA for ease of printing, but ASA or ABS would be more optimal for an outdoor setting. For ABS, acetone fumes can be used to create a very smooth surface finish, which would improve the turbine blades’ performance.

First, press a 10-32 × 9/32 threaded insert into the smaller hole using a soldering iron, then fully drive the 10-32 × 3/4 threaded rod into the hole. For the rotary shaft seal to work well, the surface it contacts should be sanded by spinning it in a drill. Sand until the shaft is smooth and the friction from the seal is minimal while still maintaining the water seal. Use a lubricant for a better seal and reduced friction.

Unfortunately, while assembling my turbine, I accidentally ripped the cables coming off my brushless motor, and I was unable to rebuild it in time. This is why I was not able to complete a fully functional prototype. Although this project may not be considered successful in the traditional sense, I hope it serves as a good starting point for anyone interested in a project like this.