## 2 Methodology
### Comparison Criteria
The category 'process' includes technical processes and systems such as cooling systems. In the next step, the methods can be assessed based on the secondary criteria, not all of which necessarily must be met. In the context of this paper, energy and environmental assessment aims to quantify the energy and environmental aspects of the investigated object as thoroughly as possible and on a robust scientific basis. Moreover, the method should be user-friendly, and the results should be easy to communicate. The objective _'thoroughness'_ comprises _completeness_ and temporal and spatial _resolution_, referring to the level of detail. The completeness is represented by the criteria 'life cycle \begin{table}
\begin{tabular}{p{113.8 pt} p{113.8 pt} p{113.8 pt}} \hline \hline
**Objective** & **Criteria** & **Partial Aspect (If Needed)** & **Underlying Question** \\ \hline \multirow{6}{*}{Applicable for the Studied Objects} & Process & Applicable to this type of studied object? \\ \cline{2-3}  & Product & Applicable to this type of studied object? \\ \cline{2-3}  & Service & Applicable to this type of studied object? \\ \cline{2-3}  & Region/Sector & Applicable to this type of studied object? \\ \hline \multirow{6}{*}{Applicable for the Studied Objects} & Life Cycle Thinking & Entire life cycle considered, cradle-to-grave? \\ \cline{2-3}  & Energy (J) & Is this physical quantity inventoried? \\ \cline{2-3}  & & Mass of Operating Materials (kg) & Is the mass of these materials inventoried? \\ \cline{2-3}  & Inventoried Physical Quantities & Mass of Construction Materials (kg) & Is the mass of these materials inventoried? \\ \cline{2-3}  & Mass of Emissions (kg) & Is the mass of these materials inventoried? \\ \cline{2-3}  & & Temperature (K), Pressure (Pa) & Are the pressure and temperature inventoried? \\ \cline{2-3}  & & Exergy (J) & Is this impact category addressed? \\ \cline{2-3}  & Impact Categories & Climate Change (kg CO\({}_{2}\)-eq) & Is this impact category addressed? \\ \cline{2-3}  & Water/Land Use/... (m\({}^{3}\), ha,... ) & Is this impact category addressed? \\ \cline{2-3}  & Noise & Is noise considered? \\ \cline{2-3}  & Efficiency Analysis & Is it referred to as a useful output? \\ \hline \multirow{6}{*}{Temporal Resolution (Dynamic Analysis)} & Is a dynamic analysis intended or possible? \\ \cline{2-3}  & Spatial or Sectoral Resolution & Is a bottom-up analysis intended? \\ \hline \multirow{6}{*}{Usability Soundness} & Pure Analysis based on Physical Quantities & Is the method scientifically sound? \\ \cline{2-3}  & Formalization (Methodological Framework, Rigor) & Are there mature and strict standards? \\ \cline{1-1} \cline{2-3}  & Data Availability & Are the required data available, e.g., as databases? \\ \cline{1-1} \cline{2-3}  & Existing studies on Cooling Systems & Are there studies assessing cooling systems? \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Objectives and criteria for comparing energy and environmental assessment methods. thinking', the inventoried physical quantities, the impact categories, and by considering the efficiency concept by referring to useful output. _Life cycle thinking_ involves upstream and downstream chains [13; 15]. Accounting from cradle-to-grave avoids burden shifting. Regarding cooling towers, a life cycle perspective reveals whether more construction material for a natural draft design or more energy consumption for fans is environmentally preferable. The criterion of _inventoried physical quantities_ refers first to the energy and material flows considered within the system boundary [12; 13; 27]. Not all methods consider both energy and all materials. Some methods disregard the mass of construction and disposal material or the emissions. Moreover, this criterion addresses whether the method considers the temperature and pressure of the energy, material flows, and environment. For cooling systems, the ambient temperature and humidity and the temperatures of the heat flows are key factors.