Introduction
Solar distillation is a sustainable and environmentally friendly method of producing clean water using solar energy. However, conventional solar stills often operate at lower efficiencies because they remain fixed and cannot continuously utilize the maximum available solar radiation throughout the day.
The primary objective of this project is to develop a solar still capable of automatic sun tracking. By continuously aligning the system with the Sun, greater solar energy can be captured, resulting in higher water temperatures, increased evaporation rates, and improved distilled water production.
System Concept
The proposed system combines a solar still with a parabolic trough solar concentrator.
The parabolic reflector concentrates incoming solar radiation onto a focal line, increasing the thermal energy available to the solar still. Higher temperatures promote faster evaporation of water, thereby improving the overall productivity of the distillation process.
To ensure maximum solar energy collection throughout the day, the concentrator must continuously face the Sun. Therefore, the development of a smooth and reliable tracking mechanism became a key part of the project.
Working Principle
The system consists of two major components:
- Parabolic Trough Solar Concentrator
- Solar Still Unit
The parabolic trough reflector concentrates incoming solar radiation onto a focal line where the receiver is placed. Heat collected at the receiver is transferred to the water inside the solar still, increasing its temperature and accelerating evaporation.
The generated water vapor rises and condenses on the cooler transparent cover of the still. The condensed droplets then flow into a collection channel and are collected as distilled water.
Disassembly and Structural Assessment
To improve the existing design, the entire structure was disassembled and carefully inspected. This process helped identify mechanical limitations and areas requiring modification before implementing the tracking mechanism.
The assessment revealed that the rotational support arrangement required improvement to achieve smooth movement. The disassembly process also provided an opportunity to strengthen structural members, improve alignment, and redesign critical mounting points.
Redesign of the Rotating Structure
To overcome the friction problem, the original rotational arrangement was removed and redesigned.
The modified system involved:
- Welding mounting bolts onto the reflector support structure.
- Installing pillow block bearings on the structure.
- Passing a steel pipe through the bearings to act as the rotational shaft.
- Mounting the shaft securely onto the base frame.
This new arrangement provided proper support to the reflector while allowing smooth rotational movement with significantly reduced friction.
