## 3 Results
### Current Status, Challenges and Future Developments
#### 3.2.3 Renewable Hydrogen Transport and Distribution  
Hydrogen transport is an essential component in the hydrogen value chain, especially in contexts where production and consumption are in different areas. Out of the total of 177 articles, 14 articles have been identified that refer to hydrogen transport, which represents 8% of the total number of articles. As can be seen in Table 7, 42.8% of the articles are based on the application of GIS techniques for the detection of the production location and the optimization of the transport route. Some 28.5% base their studies on the techno-economic analysis of the feasibility of hydrogen production and transport. On the other hand, another 21.5% examine the adaptation of existing pipelines for use in hydrogen transport. And finally, 7.3% base their studies on the safety of hydrogen transport. According to the mention of most of the articles of GIS techniques, there are methodological limitations due to the low spatial or temporal resolution of the available data, the heterogeneous data formats across regions, and the complexity of modeling multi-sectoral infrastructure systems. The studies reviewed highlight the role of GIS in addressing the logistical, technical, and economic challenges involved in the transportation of hydrogen through various means, such as pipelines, trucks, and maritime shipping. GIS technologies are used to analyze and optimize transport routes, assess infrastructure needs, evaluate terrain and environmental constraints, and support decision-making on profitability and risk management. By integrating spatial data with engineering and economic models, GIS enables a more comprehensive and informed planning of hydrogen supply chains. Some studies carry out an economic analysis as [PERSON], [PERSON] et al. [61]. They integrate indicators such as Levelized Cost of Energy (LCOE) and LCOH to identify optimal production sites and routes for transporting and exporting hydrogen from Morocco to Europe via pipelines and ships including MCDM analysis. A map is generated to show the restricted and unrestricted areas for installing production plants. To generate this map, various GIS tools are needed to integrate all the data. \begin{table}
\begin{tabular}{c c c c c} \hline \hline
**Application** & **Ref.** & \begin{tabular}{c} **Main Geospatial** \\ **Techniques** \\ \end{tabular} & \begin{tabular}{c} **Primary Uses of the** \\ **Geospatial Technique** \\ \end{tabular} & \begin{tabular}{c} **Challenges** \\ \end{tabular} \\ \hline Economic analysis & [61; 120; 121; 122] & GIS & \begin{tabular}{c} Production and \\ transportation cost \\ analysis using different \\ existing tube \\ \end{tabular} & \begin{tabular}{c} Difficult obstacles to \\ model; Lack of \\ ground data; Lack of \\ climatic data; Limited \\ GIS detail \\ \end{tabular} \\ \hline Safety & [123] & GIS & \begin{tabular}{c} Hydrogen via \\ risk assessment \\ \end{tabular} & \begin{tabular}{c} Complex modeling; \\ Few documented \\ accidents \\ \end{tabular} \\ \hline Production/Transport & [124; 125; 126; 127; 128; 129] & GIS & \begin{tabular}{c} Optimization of the \\ transport and/or storage \\ system for supply \\ \end{tabular} & \begin{tabular}{c} Non-harmonized data \\ between countries; \\ complex multisectoral \\ modeling; Public \\ data scarcity \\ \end{tabular} \\ \hline Adaptation of \\ existing Pipelines & [130; 131; 132] & GIS & \
\begin{tabular}{c} Use of existing pipes to \\ optimize transportation \\ \end{tabular} &
\begin{tabular}{c} Access to limited data; \\ Different resolution by \\ regions; Heterogeneity \\ of pipes \\ \end{tabular} \\ \hline \hline \end{tabular}
\end{table} 
Table 7: Summary geospatial techniques applied to the transport of hydrogen. For the design of pipelines [PERSON], [PERSON] et al.