Assessment of the heat load coverage level of a solar air collector in the grain drying process based on an hourly energy balance.
Received: 2026-09-14
Published: 2026-09-14
Abstract
The aim of this study was to assess, based on an hourly energy balance, the potential of a solar air
collector to cover the heat load in agricultural grain drying systems, including sunflower and rice
grain, under the climatic conditions of Beruniy district. The calculations were performed using solar
radiation data obtained from the PVGIS-ERA5 database, together with the optical-thermal balance
of the collector, useful heat output, auxiliary energy demand and required drying air flow rate. The
assessment was carried out for September and October during the period from 09:00 to 17:00. The
practical calculation conditions were adopted for the sunflower grain drying regime. The solar air
collector produced 7.326 kW·h/day of useful heat energy in September and 5.839 kW·h/day in
October. The daily heat load coverage of the drying system was 77.9% and 62.7%, respectively. In
September, the collector fully covered the drying heat load between 12:00 and 14:00, whereas in October an auxiliary heat source was required during all operating hours. The solar air collector
can be used as a hybrid heat module for preheating the drying air and reducing auxiliary energy
consumption in drying systems for sunflower, rice and other agricultural grain products. However,
the drying temperature, air flow rate and heat load should be determined separately for each product.
Keywords
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