## 3 Results and Discussion
The analysis of the data from Table 4 shows that the amount of the thermal energy \(E_{r}\) produced by the reactor and \(E_{w}\) charged to the water tank almost did not depend on the prototype operating mode. Moreover, it is important to note that the value \(E_{h}\) perfectly matches \(E_{r}\), that proves the correctness of the measuring principle and validates the use of formulas (1-3). If the thermal losses are high or the reactor is not enough hermetic, the discrepancies in the measurements between \(E_{h}\) and \(E_{r}\) are considerable, and therefore the performance characteristics cannot be properly established. Also, it can be found from Table 4 that the values of the discharging efficiency \(\epsilon_{d}\), maximum and average thermal power tend to approximately the same magnitude. This proves that the experiments had an inconsiderable sensitivity in face of the given ambient conditions. However, both energy storage densities and capacities of material considerably differ between both operating modes depending on the energy prognosis (see values \(\Delta E_{r}\) and \(\Delta E_{w}\), as well as ratios \(E_{r}/m_{s,max}\) and \(E_{w}/m_{s,max}\) in Table 4). This fact is related to the operating mode and can be explained by the difference in the material mass used in the experiments (see Table 3). Indeed, the material mass \begin{table}
\begin{tabular}{c c c} \hline \hline
**Condition** & **Fixed Packed Bed (Test 1)** & **Moving Bed (Test 2)** \\ \hline Hydration time (minutes) & 75 & 75 \\ Energy produced by reactor \(E_{r}\) (kWh) & 0.49 \(\pm\) 0.05 & 0.49 \(\pm\) 0.05 \\ Total hydration energy \(E_{h}\) (kWh) & 0.49 \(\pm\) 0.01 & 0.49 \(\pm\) 0.01 \\ Total energy charged to water tank \(E_{w}\) (kWh) & 0.42 \(\pm\) 0.05 & 0.39 \(\pm\) 0.05 \\ Energy storage density of material by reactor & \(158\)\(\pm\) 8 & 63 \(\pm\) 3 \\ energy storage density of material by water tank & & \\ energy prognosis \(\Delta E_{w}\) (kWh/m\({}^{3}\)) & \(135\)\(\pm\) 7 & 50 \(\pm\) 2 \\ Energy storage capacity of material by reactor & \(223\)\(\pm\) 24 & 89 \(\pm\) 9 \\ Energy prognosis \(E_{r}/m_{s,max}\) (Wh/kg) & \(192\)\(\pm\) 24 & 71 \(\pm\) 9 \\ Energy storage capacity of material by water tank & & \\ energy prognosis \(E_{w}/m_{s,max}\) (Wh/kg) & & \\ Discharging efficiency \(\epsilon_{d}\) & 0.86 \(\pm\) 0.06 & 0.79 \(\pm\) 0.05 \\ Average reactor thermal power \(Q_{r,day}\) (W) & 392 \(\pm\) 37 & 392 \(\pm\) 37 \\ Average water tank heating rate \(Q_{w,day}\) (W) & 336 \(\pm\) 37 & 312 \(\pm\) 38 \\ Maximum reactor thermal power \(Q_{r,max}\) (W) & 551 \(\pm\) 37 & 668 \(\pm\) 36 \\ Maximum water tank heating rate \(Q_{w,max}\) (W) & 543 \(\pm\) 39 & 487 \(\pm\) 37 \\ \hline \hline \end{tabular}
\end{table} 
Table 4: Main experimental results. used in the fixed bed test was \(2.2\pm 0.1\) kg, while the material mass spent for the moving bed test during 75 min was \(5.5\pm 0.1\) kg. At the same time, the amount of the produced thermal energy was identical for the both tests (see Table 4). In principle, the prototype performance can be directly judged by the discharging efficiency \(\epsilon_{d}\), because this indicator aggregates the constructive imperfections, such as heat exchangers effectiveness, inhomogeneities of the sorption phenomenon inside the reactor, thermal losses in the ducts, pipework, etc. The real discharging efficiency of the thermochemical energy storage process can be roughly estimated as high as 0.80-0.85. This is a reasonable lower limit being technically achievable for such a process. The discharging efficiency is better for the fixed bed test, than for the moving bed, because the average heating rate of the water tank \(\dot{Q}_{w,wt}\) was about 24 W higher for the first case (see Table 4). This fact can be explained by the denser material packing in the fixed bed, which in contrast to the moving bed configuration, resulted in the more homogeneous water vapor sorption throughout the bed. The detailed analysis of the experimental curves is presented in the following subheadings.