Numerical parametric study of the thermal and electrical performance of a BIPV/T hybrid collector for drying applications

This paper deals with the identification of influencing variables permitting to optimize the thermal and electrical performance of a building integrated photovoltaic/thermal hybrid air collector suitable for fodder drying installation through numerical parametric studies. A 2D dynamic thermal and electrical mathematical model of the solar BIPV/T component is described and validated first in steady state under a solar simulator and later in dynamic conditions with three tests models and a 35 m2 solar PV/T drying installation test bench mounted in situ. Finally, numerical parametric studies were performed using the validated model by varying the emissivity of some constitutive layers and the air gap thickness. These analyses have demonstrated, as expected, that, in order to cool PV modules and to increase their electrical performance, a relevant choice of their emissivity or of the metal absorber emissivity is important. Also, there is an optimal air gap thickness, of nearly 8 cm in the configuration studied, for which increasing the level of ventilation is less significant and thus permitting the reduction of extractors' electrical consumption. As further step, the annual thermal and electrical performance of the solar collector will be analysed experimentally and numerically in real conditions considering the fulfilment of fodder drying requirements.