## 1 Introduction
[10] studied mixtures with nitrates/expanded graphite and PCMs to obtain a composite material for solar energy storage; they showed that certain additives improve the thermal conductivity of the PCM and thus upgrade its storage efficiency. For the past few decades, several research approaches have been pursued on using PCMs in the building field, primarily to improve thermal comfort and/or reduce energy consumption. [PERSON] et al. [5] and [PERSON] et al. [11] analyzed the various types of PCM used in the civil engineering sector. Their work discussed the integration of PCMs into walls, floor heating systems, and ceilings. [PERSON] et al. [12] even used PCMs to fireproof building materials and delay the outbreak of fire. This study combines PCM with a plaster-based interior coating in order to store energy. The proactive coating (ETMV 8) presented here incorporates a micro-encapsulated vegetable oil-based phase change material (named Inertek 23), which is mainly methyl palmitate as well as methyl stearate (naturally present in many plant species). Similar studies were conducted in Florida by [PERSON] [13], who demonstrated that methyl palmitate and methyl stearate mixtures are perfectly suitable for use in gypsum boards given their thermal storage and high latent heat. Other authors have employed mixtures based on methyl palmitate and stearate in combination with other construction materials such as concrete. The research conducted by [PERSON] [14] showed that using such a fatty acid mixture as a PCM can improve the thermal performance of concrete. For their part, [PERSON] et al. [15] performed a very detailed analysis of these two fatty acids and concluded that combining the two yields the most promising PCM for energy storage in the construction industry. The phase change material used in this study (Intertek 23) offers the advantage of being compatible with other conventional building materials. Combined with a coating intended for an interior overlay application, it could be useful in reducing temperature fluctuations and smoothing out heat spikes by absorbing excess during summer or, if it proves to be efficient, the off-season as well. \begin{table}
\begin{tabular}{c c c} \hline \hline
**Chemical** & **Thermodynamic** & **Economic** \\ \hline Chemically stable & Melting point & Inexpensive \\ \hline \multicolumn{3}{c}{High latent heat of melting} \\ Non-flammable & High conductivity and density & Easy to produce \\ Non-explosive & Limited supercooling & Available in large quantities \\ Non-corrosive & Volume variation during & Durability \\  & phase transition & \\ \hline \hline \end{tabular}
\end{table} 
Table 1: PCM selection criteria [2]. This type of material is also attractive during winter, thanks to the storage and return of free energy obtained from solar radiation. This feature could have the effect of delaying the start of the heating system while reducing the sensation of a cold wall, which constitutes a source of discomfort in the building. To evaluate the efficiency and usefulness of such a product, it is essential to characterize and test it in situ. Generally speaking, the main thermal characteristics of PCMs, namely latent heat, phase-change temperatures, and enthalpy, are obtained by means of differential scanning calorimetry (DSC), which is one of the most widely used techniques to study reactions related to the transformation of a material subjected to temperature constraints. The underlying principle is to measure the temperature difference between an analyzed sample and an inert material, which does not undergo a phase change and serves as a reference [16]. When the sample is subjected to temperature stress, it will absorb or release heat, which is then quantified by measuring the change in heat flux. This method has some limitations [17] due, among other things, to the fact that only a very small quantity (a few milligrams) of material can be tested. Indeed, small mass samples are not representative of the thermal behavior of a material on a large scale [18; 19].