Introduction

As part of our renewable energy project, we have been exploring the possibility of utilizing concentrated solar thermal energy for  essential applications: freshwater production. The project aims to develop an integrated system that can harness solar energy through a parabolic trough collector and utilize the collected thermal energy for solar distillation.                                                                                                                                                                                                   The primary objective is to maximize the utilization of available solar energy while addressing important challenge —sustainable and clean water generation.

Existing Solar Collector Assessment

Instead of constructing a new collector from scratch, the team decided to refurbish and reuse the existing structure. This approach significantly reduces project cost while promoting sustainable engineering practices through equipment reutilization.

Structural Inspection and Analysis

An initial inspection of the collector revealed that the supporting framework remains structurally sound. However, several improvements were identified:

• Reflective surfaces require cleaning and replacement.
• Alignment of reflector panels needs verification.
• Focal line determination must be performed experimentally.
• Receiver mounting arrangement requires modification for improved thermal performance.                                                                                                             The adjustable tilt feature of the collector is considered a major advantage, allowing manual solar tracking throughout the day.

Concept Development

  solar still – performance table and industrial production                                                                                                                                                                                                                                                                                                                                                                                                                                                                     Several conceptual designs were evaluated during the brainstorming stage.                                                                                                                                                                                                                                                                                                                                                                                                                                Initial Concept                                                                                                                                                                                                                     The original idea involved generating steam inside a solar still basin and passing the vapor through a condensation.

The proposed sequence :

Solar Collector → Basin Heating → Steam Generation  → Condensation → Freshwater Collection.

Although innovative, further analysis revealed that this configuration would result in competition distillation processes because both require the  heat carried by the steam.

1. Energy Collection Zone

The parabolic trough collector concentrates solar radiation onto a receiver tube located at the focal line.

Functions:

• Solar energy concentration
• Thermal energy collection
• Heat transfer to the working fluid

2. Distillation Zone

A solar still basin equipped with a copper heat-exchanger coil receives the remaining thermal energy.

Functions:

• Saline water heating
• Vapor generation
• Freshwater production through condensation

Engineering Design Development

Based on the collector dimensions, preliminary engineering sketches and CAD-style layouts were developed.

Key design features include:

• Copper receiver base positioned along the focal line
• Hot water circulation loop
• Heat-exchanger integrated inside the solar still basin
• Sloped and polished alluminium sheet condenser divider
• Distillate collection trough
• Optional thermal storage provisions for future upgrades

The current design is sized around the available 205 cm × 205 cm collector and targets thermal support.