## 3 Results and Discussion in General
### Discussion in General  
The heating/cooling performance of thermal insulation panels with integrated active thermal protection depends on several factors, but mainly on the thermal conductivity coefficient of the material of the building structure to be insulated. Figure 17 is a mathematical-physical model for a monolithic reinforced concrete wall with the variables that enter the thermal performance calculation. For the parametric study, we created computational software in MS Excel. The calculation was made for the heating season. Boundary conditions: thickness of reinforced concrete bearing part of the panel \(\mathrm{b_{panel}}\) = 150 mm, thickness of thermal insulation \(\mathrm{b_{TI}}\) = 200 mm, outer dimension of the ATP pipe d = 15 mm, distance between pipes L = 0.150 m, heat transfer coefficient towards the interior \(\mathrm{h_{p}}\) = 10 W/(m\({}^{2}\cdot\)K) (according to EN 15377-1 [25] and STN 73 0540-2+Z1+Z2 [26]), heat transfer coefficient towards the exterior \(\mathrm{h_{e}}\) = 7 W/(m\({}^{2}\cdot\)K) (according to STN 73 0540-2+Z1+Z2, [26]). In the simplified calculation relations, the same wall mass temperature in front of and behind the pipe was considered in calculating the average design temperature in the pipe axis and the average surface temperature in accordance with [27; 28; 29]. The outside air temperature \(\mathrm{\theta_{e}}\) = \(-11\)\({}^{\circ}\)C, the inside air temperature \(\mathrm{\theta_{i}}\) = 20 \({}^{\circ}\)C, and the average temperature of the working medium in the ATP pipe \(\mathrm{\theta_{m}}\) = 30 \({}^{\circ}\)C were considered. The results of the parametric study were compared for the perimeter system with direct heating (VARIANT I), semi-accumulation heating (TABS system--VARIANT II), and the system with ATP (accumulation heating--VARIANT III), Figure 30.  
For thermal insulation in the thickness range of 50 to 100 mm, the heat flux to the interior \(\mathrm{q_{i}}\) (W/m\({}^{2}\)) increases while the heat loss \(\mathrm{q_{e}}\) (W/m\({}^{2}\)) decreases rapidly. For thicknesses above 100 mm, the effect of adding more insulation becomes relatively small. This is true regardless of the thickness of the concrete core, which has almost no effect on the heat flux. On the other hand, the effect of pipe spacing on heating performance is evident; despite the small effect on the heat flux to the interior, increasing the thickness of the concrete, and hence the inertia of the wall, can reduce the energy demand for heating [25]. The storage capacity, which is expressed as a time constant, can range from approximately 2.5 to almost 8 h for a system with a pipe embedded in a solid concrete core [30]. For example, [PERSON] et al. [31] report that in Milan, Italy, the energy demand for high inertia walls can be up to 10% lower than for low inertia walls. [PERSON], [PERSON], and [PERSON] [32] calculated for the climate of Riyadh, Saudi Arabia, a reduction in energy demand for increasing wall thickness and a heating energy saving of up to 35% due to thermal mass optimization. Other studies [33; 34; 35] highlight the importance of concrete  
Figure 29: Display the working substance’s temperature in the supply (red) and return (blue) pipes from ATP1, ATP2, and underfloor heating for the last 24 h [15]. thickness for the thermal dynamics of buildings, which must be considered when designing new construction, renovation, or control system.