Optical and Thermal Performance of Linear Fresnel Reflectors in Eastern Mediterranean Conditions

Abstract

Linear Fresnel Reflectors (LFR) are a type of concentrated solar collector that uses direct solar radiation (DSR) to provide useful heat for a range of applications, including power generation, heating and cooling. This study introduces a simplified analytical method for predicting the optical and thermal performance of LFR systems using only the geometric parameters and meteorological data of a location. In this analysis, the Incident Angle Modifier (IAM) and DSR are calculated using long-term data from open-access weather datasets, offering analysis from minute-scale to annual resolution, without the requirement of computationally expensive methods such as ray-tracing or extensive onsite measurements. The model is validated against experimental data from an installed LFR system at the Cyprus Institute (CyI) in Nicosia, Cyprus, demonstrating good agreement in both solar and useful energy output. The latter is derived as the product of the predicted DSR, which closely matches pyrheliometer measurements over a four-year period, and the accurately reproduced IAM. Overall, the method provides a reliable estimation of the thermal performance, offering a practical tool for early-stage design for any location of interest, yielding results significantly faster and at a fraction of the computational cost compared to ray-tracing and CFD approaches.