## 3 Results and Discussion  
Two types of hydration experiments were performed on the installation prototype: the reactor was running as the fixed packed bed (test 1) or as the moving bed (test 2). All the hydration experiments were done under laboratory atmospheric conditions, using the ambient moist air. The heat released during the hydration reaction was used to heat up the water tank. In all experimental cases, the material was dehydrated in the laboratory oven at 150 \({}^{\circ}\)C and so its initial water uptake was less than 0.01 kg/kg. This resulted in an initially high adsorption potential and led thus to a high initial step in the thermal power at the reactor boundaries at \(t=0\) min, which will be analyzed later. Furthermore, the relative air humidity under ambient conditions was measured from 41% to 52% at 20 \({}^{\circ}\)C, which cannot always exist under winter climate conditions. The initial and experimental conditions for the modes (i) and (ii) are listed in Table 3.  
It has to be noted, that only two experimental datasets are presented and analyzed here. These results provide the necessary and sufficient information about the prototype functioning under tested \begin{table}
\begin{tabular}{c c c} \hline
**Condition** & **Fixed Packed Bed (Test 1)** & **Moving Bed (Test 2)** \\ \hline Anhydrotus bed mass \(m_{s}\) (kg) & \(2.2\pm 0.1\) & \(2.2\pm 0.1\) \\ Total processed anhydrous solid mass \(m_{s,max}\) (kg) & \(2.2\pm 0.1\) & \(5.5\pm 0.2\) \\ Initial hydration state \(x_{0}\) (kg/kg) & \(<\)0.01 & \(<\)0.01 \\ Solid mass flow rate (kg/s) & – & \(1.2\times 10^{-3}\) \\ Dry air mass flow rate \(\dot{m}_{r}\) (kg/s) & \(3.3\times 10^{-2}\) & \(3.3\times 10^{-2}\) \\ Water mass flow rate (kg/s) & \(3.4\times 10^{-2}\) & \(3.4\times 10^{-2}\) \\ Ambient air temperature (\({}^{\circ}\)C) & \(17.1\) & \(18.7\) \\ Inlet air moisture content (kg/kg) & \(6.0\times 10^{-3}\) & \(7.6\times 10^{-3}\) \\ Inlet water vapor pressure (mbar) & \(9.8\) & \(12.3\) \\ Heat recovery & Activated after 28 min & Activated after 29 min \\ \hline \end{tabular}
\end{table} 
Table 3: Initial and experimental conditions. conditions, and clearly demonstrate the performances and flaws. Other tests were also carried out, but the obtained results were equivalent because of the little variation of the atmospheric conditions. As follows from Table 3, the experimental conditions were quite similar between both tests. The average ambient temperature, as well as the air absolute humidity, were 1.6 \({}^{\circ}\)C, and respectively \(1.6\times 10^{-3}\) kg/kg higher for test 2 than for test 1. Nevertheless, the experimental results can be compared. The time instant, when the heat recovery by the exchanger HX2 (see Figure 2) was switched on, was also identical for both experiments (see Table 3). The main performance indicators for the fixed and moving bed experiments are presented in Table 4. The uncertainties in Table 4 were calculated with the uncertainty propagation method [37]. The total hydration energy \(E_{h}\) was calculated by integrating equation (2) over time. To simplify the calculation, the reaction heat \(\Delta H_{s}\) was taken constant as given in Table 2. The energy densities \(\Delta E_{r}\) and \(\Delta E_{w}\) were found from equation (5), considering the total anhydrous material mass \(m_{s,max}\) from Table 3 and the packing density of the anhydrous composite from Table 2. Additionally, the energy storage capacity (Wh/kg) of material can be found in form of the ratios \(E_{r}/m_{s,max}\) and \(E_{w}/m_{s,max}\) using equation (3) and data from Table 3.  
Although, the total hydration time spent in the moving bed operating mode was 168 min, the results are shown only for the first 75 min, when 5.5 kg of solid mass was processed. This allows the fixed and moving beds characteristics to be compared within the same time interval.