Long-Term Performance Analysis of Solar Collectors

Abstract

AbstractPrediction of long-term performance of solar collectors is required for optimum solar system design. Availability of solar radiation above critical level ascertains utilization of solar radiation for useful energy gain by the systems. F chart method or the utilizability methods developed by Klein, Collares-Pereira, and Rabl are mainly used to simulate long-term performance of solar flat plate collectors. In this paper, long-term performance analysis of two different types of solar thermal collectors has been studied using utilizability method. Long-term radiation data on tilted surface has been simulated using Klucher’s model and has been used to estimate daily utilizability and useful energy gain by a flat plate collector and evacuated tube collector. The annual performance of these two types of collectors is compared under different climatic conditions namely cold desert climate and hot semi-arid climate, to understand applicability of these systems to meet the energy demand of these places. It has been observed that evacuated tube collectors show better performance during winter months compared to flat plate collectors. The F chart method is also used to find the fraction of demand of hot water for domestic applications that can be met by a flat plate collector system for different collector area. It has been observed that 30–55% of the demand can be met by flat plate collector water heating system based on the collector area.KeywordsLong-term performance analysisUtilizabilityKlucher modelFlat plate collectorEvacuated tube collector