## 5 Conclusions  
Geospatial techniques will play a key role in CET as enablers of emerging technologies. Because of their characteristics and applications, their impact on technologies such as renewable hydrogen can make all the difference. Renewable hydrogen is a key pillar for achieving the decarbonization targets set for 2050. Its versatility allows it to be used in a wide range of applications, such as electric or thermal power generation, seasonal storage, or mobility. It is therefore postulated as a key agent in the decarbonization of society as a substitute for fossil fuels and as a complement to renewable energies. A system based on renewable hydrogen allows for a more efficient use of renewable resources at the local level and more precise adjustment of equipment sizing and improved profitability of the installation. \begin{table}
\begin{tabular}{c c c c} \hline \hline
**Limitation/Challenge** & **Impact on Results** & **Implication for Future Research** & **Stages of the HVC** \\ \hline Lack of high-resolution or standardized spatial data & Reduces accuracy in site selection and comparative across regions & Development of global, standardized geospatial datasets & Production; Storage; Transport and Distribution; End-uses \\ Fragmented and inconsistent datasets & Causes unreliable or incomplete analyses & Improvement of data harmonization and interoperability & Production; Transport and Distribution; Cross-cutting \\ Cloud cover in satellite images & Limits solar resource assessment & Use of alternative sensors or correction methods & Production; Transport and Distribution \\ High computational complexity & Restricts large-scale or real-time modeling & Optimization of algorithm, use high-performance computing & Production; Transport and Distribution; End-uses; Cross-cutting \\ Long computation times for complex models & Delays simulations and scenario analysis & computing, or cloud solutions & Production; Transport and Cross-cutting \\ Limited deployment of sensors in remote areas & Inhibits real-time monitoring in key locations & Development of low-cost, resilient IoT technologies & Production; Storage; End-uses \\ Poor integration of spatial and economic models & Incomplete cost analyses of hydrogen systems & Combination of GIS with techno-economic frameworks & Production; Transport and Distribution \\ Inaccurate or sparse underground/geological data & Affects storage site suitability and safety & Enhancement of geophysical mapping and data collection & Storage; Transport and Distribution \\ Non-harmonized data & Blocks cross-border & Promotion of international standards and open data & Transport and Distribution; Cross-cutting \\ Unreliable or non-geolocated & Affects planning of hydrogen refueling stations and demand analysis & Standardization of data collection and ensuring spatial tagging & End-uses \\ Lack of training datasets for AI/image-based & Limits automation in component manufacturing & Creation of labeled image databases for machine learning & End-uses; Cross-cutting \\ Complex integration of multi-source geospatial data & Hinders holistic system analysis & Building unified platforms for GIS, IoT, and remote sensing & All \\ Lack of open-access or updated databases & Limits reproducibility and collaboration & Proportion of public repositories and government-supported open data & All \\ \hline \hline \end{tabular}
\end{table} 
Table 10: Summary of data limitations and technical challenges. This systematic review of 177 peer-reviewed studies published between 2019 and 2025 offers an integrated view of how geospatial techniques support every stage of the renewable HVC. By combining quantitative bibliometric analysis with qualitative mapping of methods, it becomes clear that nearly half of all research focuses on hydrogen production, with a further sixth addressing end-uses and just over a tenth on storage, while transport and cross-cutting topics complete the landscape. The research carried out demonstrates the role of geospatial techniques for the development of a hydrogen economy.