Quantitative review on recent developments of flat-plate solar collector design. Part 1: Front-side heat loss reduction

Abstract

Several studies demonstrated novel and effective design solutions for the FPC thermal performance enchantment by the front side heat loss reduction. However, these design improvements were tested under different climatic and operating conditions. This fact makes it almost impossible to compare these design improvements. The following study quantitatively analyses the current flat-plate solar collector design developments, focusing on reducing front-side heat loss. It also performs a simulation analysis to demonstrate the thermal performance improvement of the chosen design solutions for three specific applications. The literature review was performed to identify the most promising design solutions. Then, the considered design solutions were modelled using the validated detailed theoretical model of a flat-plate solar collector (FPC). Finally, the modelling results were used to perform the thermal performance simulation analysis for Würzburg (Germany) climatic conditions and constant mean fluid operating temperatures of 50, 75, and 100 °C. The simulation results indicated that applying the considered design solutions to decrease the front-side heat losses could significantly increase the FPC thermal performance. Moreover, for high-temperature applications, where the front-side heat loss is a crucial factor determining the FPC thermal performance, there is more than a significant potential for the FPC thermal performance enchantment. To sum up, our findings indicate a significant thermal performance improvement potential that could increase the application range of FPCs and make them more competitive for a broader application area.