Field measurement on the wind and thermal microenvironment of distributed PV array

Abstract

The wind and thermal microenvironment around PV arrays play an important role on their structural safety and power output. Most existing research predominantly focuses on numerical simulation methods, which usually involve various idealized assumptions that may lead to distortions in the simulation results. This study employs field tests to investigate the wind and thermal microenvironment of distributed PV array in a high-altitude cold region, which has higher wind speeds, lower atmospheric pressure and colder temperatures. The experiment compared the roof microenvironment with and without the PV arrays, and analyzed the wind speed, roof and PV panel temperatures and wind loads. The experimental results indicated that the installation of PV array significantly alters the wind environment and convective heat transfer on the roof, reducing the surface temperature of the roof, decreasing radiation and convective heat transfer and improving energy efficiency and sustainability. The convective heat transfer intensity at the front of the PV array reached 36.19 W/(m2·°C) at 15:00, which is twice the convective heat transfer coefficient of the unoccupied roof. The surface temperature of the PV panels reached its peak of 49.47 °C around 13:30. The wind load fluctuations on the front side of the PV panels were found to be significant, especially in the first row of panels, which calls for careful design and installation methods to ensure the structural integrity and safe operation of distributed PV array.