## 1 Introduction  
The effective utilization of renewable energy sources has the potential to lower the rising global energy demand and to help establish a future based on sustainable use of energy. In particular, thermal energy storage is a key element in this prospect to adjust the imbalance between heat demand and supply, as well as to limit wastes and overproduction of heat [1; 2; 3; 4]. Three different types of thermal storages exist and can be discerned based on the form in which heat is stored: Sensible (sensible heat storage, SHS), latent (latent heat storage, LHS), or chemical (chemical heat storage, CHS). The functioning principles of these energy storage technologies have already been extensively described in several sources in the literature [5; 6; 7; 8; 9], and thus will not be explained further hereby. The so-called phase change materials (PCM) allow storage of latent heat during reversible phase transitions. Latent heat storage presents the advantage over established sensible heat storage of providing higher energy densities due to the charging phase occurring at a constant temperature while the storage material is melting. Additionally, they allow the usage of more compact unit sizes and an isothermal behavior during heat transfer processes [6]. The PCM selection plays a major role in the efficiency of an LHS system. In order to achieve this, PCMs need to possess several properties among which are congruent phase change, thermal stability and high enthalpy of phase change. Moreover, additional desired properties include non-corrosiveness, non-flammability, low to no degree of supercooling, low to no degree of toxicity, biodegradability and sustainability [3]. Esters are a class of organic materials that derive from the combination of a carboxylic acid with an alcohol. Similar to alcohols and carboxylic acids, esters are biodegradable and can be bio-based if derived from renewable feedstock. However, they are characterized by higher chemical stability and lower corrosivity compared to their precursors. Although esters have already been limitedly tested and their thermal properties investigated, they are still far from being established as PCM. There is a clear lack of experimental data in regards to esters' thermal behavior and properties due to their low commercial availability and high prices. [PERSON] et al. [10], [PERSON] et al. [11] and [PERSON] et al. [12; 13] investigated the thermal behavior of different types of both commercially available and self-synthesized esters, namely linear saturated esters, esters derived from stearic acid coupled with glycerol and other linear alcohols, and even-numbered fatty acid esters of myristyl alcohol. [PERSON] et al. [14] performed a study on fatty esters derived from five different types of even-numbered fatty acids (Myuristic Acid MY (C\({}_{14}\)), Palmitic Acid PA (C\({}_{16}\)), Stearic Acid SA (C\({}_{18}\)), Behenic Acid BE (C\({}_{22}\))), coupled with alcohols of different chain lengths (methanol (C\({}_{1}\)) and 1-decanol (C\({}_{10}\))). All esters showed promising thermal properties with supercooling below 5 \({}^{\circ}\)C, thermal stability over three heating-cooling cycles, and congruent phase change ranging from 15 to 45 \({}^{\circ}\)C, which supports their suitability as PCM for low to mid temperatures applications such as space heating [15; 16; 17]. In addition, some trends similar to what had been reported by [PERSON] et al. [18] and [PERSON] et al. [19] correlating the chemical structure to the thermal properties have emerged. Although studies on the correlation between chemical structure and thermal properties have been previously conducted and reported in the literature [20; 21; 22], in order to allow esters to develop as established PCM for a sustainable utilization of energy, further insight is needed.