Investigation of the lumber drying process using air-cooled PVT panels under Isparta province conditions

Abstract

This study investigates the feasibility of using an air-cooled photovoltaic/thermal (PVT) system as a renewable heat source for lumber drying under the climatic conditions of Isparta, Türkiye. The analysis is based on a real facility equipped with 200 rooftop photovoltaic modules (455 W each), whose annual power generation was measured as 141.8 MWh in 2024. Theoretical simulations demonstrated that converting the existing PV array into a PVT configuration increases annual electrical output by approximately 4 %, reaching up to 5 % during summer months due to the cooling effect of the airflow behind the panels. The recovered heat from the air stream circulating behind the collectors can effectively preheat the drying air, reaching outlet temperatures of 50–60 °C under peak summer conditions. However, the produced thermal energy (≈0.75–1.38 MWh/day) is insufficient to fully meet the drying load of a 166.7 m³ kiln but can make a substantial contribution as a hybrid auxiliary source, reducing both fossil fuel consumption and operating costs.