*7.3.1. Phase 1: objectives and scope definition*

At this phase, it is important to fully understand the system under consideration and then be able to define the objectives and scope of the analysis. The functional unit and the system limitations are defined during this phase. The functional unit will allow to compare the two different systems based on a common function.

Therefore, the following aspects are defined at this phase for the case study:


**Figure 7.** Life cycle Assessment phases.


#### *7.3.2. Phase 2: life cycle inventory analysis*

During this phase, data are compiled for the inventory of the system at issue. For this analysis, the life cycle inventory (LCI) of the ACASS system is obtained from primary sources. The information was directly quantified on site, and some data are obtained from suppliers, some assumptions have also been made in the absence of some data, such as the type of transport used. For the LCI of the CAC system, the material content and percentages have been taken from the literature [57], suited to the requirements of the analysis. For the use stage, the equipment maintenance, part replacement, and electrical energy consumption are taken into consideration.
