## 3 Maritime-Port Operations That Are Likely to Be Carried out with a More Sustainable Energy Model  
Ports host numerous facilities that serve both the cargo they handle and the ships transporting it. These facilities are becoming increasingly specialized to enhance efficiency in cargo operations. This specialization shapes the energy consumption model of each facility or terminal, as some require more internal movements than others. For example, container terminals typically require more dockside machinery than bulk terminals, which results in higher absolute energy consumption and contributes significantly to the overall increase in port energy demand--even if, on a per-unit basis, they may operate with greater energy efficiency. This means that achieving a more sustainable energy model requires focusing heavily on optimizing energy consumption patterns within port terminals, which account for 43% of the port's total energy use. Given their significant impact, enhancing efficiency and integrating low-carbon energy solutions in these terminals is essential to driving the overall decarbonisation of port operations.  
To illustrate the above, the results from Valencia, one of the four most relevant ports of general interest in the Spanish state, have been examined. According to its 2016 GHG emissions report [11], Scope 3 of its emissions inventory includes activities carried out within the port premises--managed either by concessionaire companies or directly by the port authority--as well as road and maritime transport operations. Among these, the activities under the port authority's jurisdiction represent the most actionable category, as road and maritime transport typically fall outside of direct operational control.  
The port's activities can be classified under Scope 3 according to the activities classification given by the Climeport project and included in the 2016 \"GHG emissions report of the port of Valencia\" (see Table 1).  
These activities have an annual energy consumption of 186 GWh, which corresponds to 43% of the total energy consumption of the port. In addition, the port authority's own consumption--an extra 2%--should be added. Therefore, the managing body's direct capacity for action accounts for 45% of the total energy consumption [11].  
In addition to these activities, other possible sources for the reduction of greenhouse gases in ports are road transport and maritime transport, whose regulation goes beyond the direct management of port authorities but which they can facilitate by incorporating technology such as shore-side electricity or by using alternative fuels for trucks entering and leaving the port.  
The integration of renewable energy generation systems within port environments presents several strategic opportunities. On the one hand, such systems increase the energy autonomy of ports. On the other, surplus energy can be redirected toward the production of alternative fuels (e.g., hydrogen, methanol, and biofuels) or used to power dockside operations through electrification. This clean energy can then be utilised in port terminals to facilitate the transition from fossil fuels to clean fuels or electricity during dockside cargo handling operations.  
For all of these reasons, there is a clear need to allocate resources toward analysing the marine environment as a means to expand port capacities for clean energy generation and support the broader energy transition.