One-dimensional exergy analysis of an unglazed low-cost PhotoVoltaic/Thermal solar collector

In this paper, a one-dimensional finite-volume model of a low-cost unglazed flat-plate PhotoVoltaic/Thermal (PVT) solar collector is presented. Mass, energy and exergy balances are performed for each element of the computational domain, discretised along the flow direction. Experimental and numerical data are compared. Exergy destruction rate and exergetic efficiency are evaluated for each element of the computational domain. In addition, the effect of the main design/operation parameters on the collector exergetic performance is also investigated. The comparison between experimental and numerical data in terms of PVT outlet temperature shows an absolute error and a standard deviation of -1.06°C and 0.628°C, respectively. The calculated exergetic efficiency varies between 0.134 and 0.165 during the experimental measurements. For lower flow rates, the relationship between the total exergetic residual and inlet temperature is almost linear.