Warming beehives with solar energy stored in water

Abstract

This study presents the possibility of utilizing a passive solar system in sunny places, which collects solar energy by using polyethylene sheet to trap the long-wave thermal radiation and store it in water for warming the internal environment of beehives and its effect on nest temperatures, honey area, pollen area, sealed brood area, and the number of occupied frames. A number of six Langstroth hives containing honeybee colonies of equal strength from the species of hybrid Carniolan are divided into two groups as follows: a control group (untreated hive), and modified beehives that have been treated with the solar energy storage system. The solar energy storage system consists of an insulated wooden drawer located under the beehive's bottom board, containing sealed water bags, and is covered with polyethylene sheet. Solar energy stored in water is used to reduce the variation of inside air temperatures between daylight and night time. The highest values of the honey area, pollen area, sealed brood area, and the number of occupied frames (916 cm2, 842 cm2, 3688 cm2, and 9 frames, respectively) were shown for the modified beehives at the end of March, while the lowest values (98 cm2, 219 cm2, 911 cm2, and 3 frames, respectively) were recorded for the control groups of beehives at January, respectively. In modified beehives treated with a solar energy storage system, there was a significant rise in hive temperature, honey area, pollen area, sealed brood area, and bee population. So, it is recommended to use the new modification for warming beehives.