Design of a Low-Cost Parabolic Concentrator Solar Tracking System: Tubular Solar Still Application

Abstract

The high cost of the solar tracking systems is the major obstacle facing the growth of the solar harvesting technology. Therefore, reducing the solar tracking cost is necessary for developing this important energy sector. This study developed a simple and low-cost solar tracking system for parabolic concentrator (PCST) assisting tubular solar still (TSS). A single-axis solar tracking mechanism is developed based on two small light-dependent resistors (LDRs) shielded by a blank sheet which keeps the two cells shielded from sunlight. When the sunlight moves, one of the two LDRs will gain some light activating a switch to turn on the driving motor moving the system in the opposite direction till the LDR shielded again. By this simple mechanism, the two LDRs are shielded from sunlight all the time and consequently, the solar collector is always facing the sunlight. A simple parametric study is also conducted for an efficient PCST-TSS device with higher freshwater productivity. The performance of the most promising five design categories is compared. Results showed that the lowest cost tracking system was 34.6% lower than the highest one. Moreover, the lowest CPL was $0.0074/L which is 43.1% lower than the highest CPL category. Moreover, a comparison with other studies showed high potential for the present significant reduction in the cost which ranges between 43.1% and 87% compared with the recent related studies. The developed device is fully self-reliance and suitable for rural and isolated communities having limited infrastructure.