Performance Evaluation of an Evacuated Flat Plate Photovoltaic-Thermal (PVT) Collector for Heat and Electricity

摘要

The photovoltaic (PV) systems produce heat and electricity at the same time. Heat produced by conventional PV systems is of low-grade nature that cannot be used efficiently in high temperature application. In this article a novel PV thermal air collector has been worked out that can produce heat of high-grade nature as well as electricity. To obtain high temperature vacuum has been created between the solar cells and glass glazing that will reduce the thermal loss. Currently, in this work, a mathematical model is presented for single glazed evacuated flat plate photovoltaic-thermal (EFPVT) air collector to investigate its performance under different working conditions. The model is established on heat balance equations constructed for each component of the EFPVT air collector, considering a steady state heat transfer. MATLAB software is used to develop the computer code for the heat balance model and to run the iterative simulations. Simulations are performed at different mass flow rates (0.001-0.08 kg/s), collector length (1-10 m) and different configurations (evacuated/non-evacuated, with PV lamination and without PV lamination). The results indicate that thermal efficiency for EFPVT collector is higher and achieved higher outlet air temperature. A slight reduction in PV electrical efficiency is also observed due to rise in absorber temperature, in EFPVT collector case as compared to conventional non-evacuated configuration. The proposed mathematical model is suitable for steady state simulation and can successfully predict the system's electrical and thermal performance, in good conformity with the literature.