Empirical Model for Estimating the Exergy of Solar Radiation in Chile

摘要

Exergy is a thermodynamic property that represents the potential work that can be delivered by a system. In that regard, the exergy of solar radiation could constitute a supporting tool for assessing the potential locations for the deploying of new solar energy project, as well as for evaluating the technologies to be considered. The present work, proposes an empirical model for the exergy of solar radiation, using meteorological data measured in Santiago, Chile. The developed model considers the clearness index as input variable, allowing to be applied throughout the country, using the satellite based global radiation estimations. Thirteen different models were analyzed in a regression routine, evaluating its effectiveness, and selecting the best approximation. An innovative experiment was also carried out, which allowed to verify the empirical model and compare it with other models proposed in the literature. The experiment follows the guideline of a test rig reported in the literature, which considers a photovoltaic panel and several sensors that allow to assess an accurate energy (and exergy) balance.