# Comparative Study of Natural Fibres to Improve Insulation in Wooden Beehives Using Sensor Networks
## 3 Results  
### External Heating Source  
The raw results of external insulation laboratory tests for each insulating material are shown in Figure 5. The evolution of the different monitored variables is similar among all  
Figure 4: Communication architecture of the field sensor network. materials. The graph illustrates the evolution of temperature and humidity both inside and outside (i.e., in the chamber) of the hive over the test period. In all cases, the external temperature rises rapidly, while the interior temperature of the hive increases more gradually, demonstrating the insulating properties of the hives. Similarly, external humidity decreases quickly due to the absence of a humidity control system, allowing humidity to escape the chamber easily. Inside the hive, the humidity initially increases because of limited air exchange with the chamber but eventually begins to decrease as the interior air starts to exchange more actively with the chamber. The overall cumulative temperature area for all materials is smaller than that of the control experiment. However, it should be noted that for comparison purposes, the commercially available materials employed had varying thicknesses, so normalisation was crucial. Similarly, due to external factors like the starting temperature outside the chamber, it is essential to begin comparing materials at a consistent temperature (22 \({}^{\circ}\)C). This requirement results in different starting times for each experiment. Figure 5: Graphical representation of the indoor and outdoor temperature and humidity variables obtained in the laboratory test for (**a**) control hive, (**b**) rock mineral wool hive, (**c**) wood fibre hive, (**d**) black agglomerated cork hive, and (**e**) white agglomerated cork hive. The yellow area has been calculated at 22 \({}^{\circ}\)C indoors and for a time of 1 h to compare the insulating capacity of each material. The results are consistent across experiments and materials (Online Resource 1), with no significant differences between replicates. Considering this, the integration of variables among materials, along with descriptive statistics and an analysis of variance for the variables \"area/thickness\" and \"maximum temperature after 1 h of exposure at 60 \({}^{\circ}\)C\", are shown in Table 2.  
The control hive has a significantly larger temperature area and a higher area/thickness ratio compared to the other hives. This observation is also mirrored in the maximum temperatures recorded: the control hive reached 27 \({}^{\circ}\)C, while hives with natural fibres displayed reduced temperatures, 26.1 \({}^{\circ}\)C for white agglomerated cork and wood fibres, and 25.6 \({}^{\circ}\)C for black agglomerated cork and rock mineral wool. In terms of thermal insulation, specifically referring to the maximum internal temperature after 1 h with an external temperature of 60 \({}^{\circ}\)C, the comparative ANOVA analysis results (presented in Table 2) show no significant differences between the four selected materials: black agglomerated cork, white agglomerated cork, wood fibres, and rock mineral wool, as illustrated in Figure 6b. Any of the selected insulators offers significant differences in performance when compared to the control hive, which lacks insulation.