✨ A Vision for Sustainable Energy – From Waste to Watts
Design and Simulation of a Mini Water Turbine Generator Based on 3D Printing
Using Recycled Plastic Bottle (PET) Material with SolidWorks Analysis.This project was a collaborative effort led by Ali Muda Akasyah, with contributions from myself and fellow team members Ismail, Kurniawati, Suharjo, S.Si., M.T., and Zikri, ST., M.T. Each of us brought unique expertise to the table—from design and simulation to renewable energy systems and prototyping—ensuring that the project not only worked in theory but also translated into a practical and sustainable solution. The teamwork and shared commitment were what made this project successful, blending innovation with real-world application.
In a world grappling with the twin challenges of plastic pollution and the need for clean energy, this project explores a powerful synergy: transforming discarded plastic bottles into a functional source of renewable power. The goal was to design, analyze, and build a mini water turbine generator using filament made from recycled Polyethylene Terephthalate (PET). By leveraging the precision of 3D printing and the predictive power of Computer-Aided Engineering (CAE), this research demonstrates a complete, sustainable engineering workflow—from digital design to a tangible, eco-friendly prototype.
This isn’t just about building another turbine; it’s about reimagining waste as a valuable resource and making renewable energy technology more accessible, affordable, and environmentally conscious.
✨ The Design Philosophy: Simplicity Meets Performance
The heart of the project lies in a carefully crafted design, brought to life in SolidWorks 2025. The turbine was conceived as a modular system consisting of three core components, each optimized for 3D printing with recycled PET:
- The Kaplan-Style Impeller: This is the engine of the turbine. Its complex, curved blades were meticulously shaped to capture the maximum energy from low-pressure water flow, converting the fluid’s kinetic energy into rotational mechanical power.
- The Volute Housing: This shell encases the impeller and is engineered to guide the incoming water into a vortex, directing it onto the blades at the most effective angle to maximize torque.
- The Covers: Front and rear covers seal the assembly, ensuring a pressurized, leak-proof system while providing structural support for the rotating shaft.
The entire assembly was designed with Design for Additive Manufacturing (DFAM) principles in mind, minimizing overhangs and complex geometries to ensure a smooth, support-free printing process.
✨ Virtual Testing: Engineering a Robust and Efficient Turbine
Before a single layer of plastic was printed, the turbine underwent rigorous virtual testing to predict its real-world performance. This crucial step, performed using SolidWorks’ integrated simulation tools, saved time and resources while allowing for significant design refinement.
1. Computational Fluid Dynamics (CFD) Analysis
How would water actually behave inside the turbine? To answer this, a CFD analysis was conducted. By simulating a steady flow of water at a pressure of 0.6 MPa, we could visualize the invisible forces at play.
The simulation revealed a beautifully efficient flow path, with water accelerating as it spiraled through the housing and struck the impeller blades. Most importantly, it quantified the turbine’s potential, predicting a stable torque of 0.079 N·m. This critical value confirmed that the design was capable of generating useful mechanical power.
2. Testing the Strength: Finite Element Analysis (FEA)
Could a turbine made from recycled plastic bottles withstand the intense pressure of flowing water? To validate its structural integrity, an FEA was performed. The pressure loads predicted by the CFD simulation were applied to the 3D model.
The analysis calculated the internal stresses using the Von Mises criterion, a standard for predicting the failure of ductile materials like PET. The results were outstanding: the maximum stress was found to be 35.94 MPa, well below the material’s estimated yield strength of 55 MPa. This translated to a minimum Factor of Safety (FoS) of 1.53, indicating that the design is robust and safe for operation under the simulated conditions. The analysis also predicted a maximum deformation of just 0.394 mm, confirming the structure is sufficiently rigid.
✨ From Digital to Physical: The Power of 3D Printing
With the design validated, the digital blueprints were brought to life. The components were fabricated on a standard FDM 3D printer using filament extruded from recycled PET bottles. The choice of material was deliberate—not only is PET chemically resistant and mechanically strong enough for this application, but its use also closes the loop on plastic waste.
The resulting prototype is a testament to the power of this integrated workflow. It is lightweight, cost-effective, and a tangible example of how circular economy principles can be applied to create sophisticated engineering solutions.
✨ Skills demonstrated
- Mechanical Design & CAE:
- SolidWorks: 3D modeling of fluid-handling components (impeller, housing), assembly design, and preparation for simulation.
- Computational Fluid Dynamics (CFD): Hydrodynamic analysis using SolidWorks Flow Simulation to predict torque, pressure, and flow velocity.
- Finite Element Analysis (FEA): Structural analysis to validate the design’s ability to withstand fluid pressure, calculating Von Mises stress and deformation.
- Sustainable Engineering & Materials:
- Circular Economy: Application of design principles using recycled materials (PET).
- Material Science: Understanding and applying the mechanical properties of recycled PET for a functional engineering application.
- Additive Manufacturing:
- 3D Printing (FDM): Fabrication of a functional prototype from recycled PET filament.
- Design for Additive Manufacturing (DFAM): Optimizing part geometry for successful and efficient 3D printing.
- Renewable Energy Systems:
- Turbomachinery Design: Applying principles of fluid mechanics to design an efficient Kaplan-style turbine runner.
- Micro-Hydro Power: Conceptualizing and designing a system for small-scale, decentralized energy generation.