**5. What can be one strategy for working fluid selection?**

In the process of working fluid selection (**Figure 7**), the knowledge of thermodynamic properties is essential, but the step consisting of the utilization of virtual machine or process simulator software is also essential to screen some working fluids and reduce the list of potential candidates. For this essential step, the question of the thermodynamic model, predictive or not, and its accuracy is also essential. Once a list of fluids has been selected, it will be necessary to refine the thermodynamic model through data acquisition and adjustment of the parameters of the selected thermodynamic models [13].

The working fluid can be a pure fluid or a mixture. The advantage of a zeotropic mixture is its possibility to adapt the temperature glide to the variation of temperature of the heat or cold sources. With the adapted zeotropic mixture, we have the possibility to the irreversible low in heat exchanger. Zhang et al. [34] have proposed a very interesting analysis of the performance of an ORC in the context of ocean thermal energy conversion in 2022. Similar utilization of zeotropic working fluid is realized with the utilization of geothermal water as a heat source (Liu et al. [35]). It was observed that the utilization of the adapted zeotropic working fluid will lead to better matches of the temperature profiles of the working fluid and the heat source [13].

**Figure 7.** *A strategy for working fluid selection [33].*

*Utilizing Computational Methods to Identify Low GWP Working Fluids for ORC Systems DOI: http://dx.doi.org/10.5772/intechopen.1003740*
