## 4 Discussion  
Section 3 presents the concept of an algorithm that determines a local passage route based on local hydrometeorological conditions and knowledge of the ship's capability plot. The algorithm works by dividing the area through which the route is to pass into smaller squares (e.g., an area of 10.2 km\({}^{2}\) is shown in the publication) where environmental conditions are assumed to be constant, and then determining the route through each square. When moving from one area to the next, the route is recalculated based on the new environmental conditions. Despite the simplicity of the algorithm's structure, several potential limitations to its application were identified during implementation:  
* The ship's capability plot must be available. As mentioned in the publication, any DP 2 or higher vessel is required to have it, but if the route is being determined for a DP 1 vessel or one without such a system, the capability plot would need to be calculated independently. * If the route needs to be updated during operation, the vessel must monitor wind speed in real time and measure or estimate the speed of the sea current. * The speed of route calculation also depends on the programming language used. The algorithm described in the paper was written in Python and also used as part of code written in C#. Both are high-level languages. If the algorithm were implemented in C or C++, shorter route generation times could be achieved. Currently, the times are as follows: for a 6 \(\times\) 6 grid--0.05 s, for an 11 \(\times\) 11 grid--0.36 s, for a 16 \(\times\) 16 grid--0.47 s, and for a 21 \(\times\) 21 grid--0.85 s. \begin{table}
\begin{tabular}{c c c c c c c c c c} \hline \hline \multirow{2}{*}{**Phase**} & \multirow{2}{*}{**S**} & \multirow{2}{*}{**V**} & \multirow{2}{*}{**t**} & **Course** & **True** & **Conv. Force** & **Sum** & **Fuel** & **Energy** \\  & & & & [”] & **Wind** & **[X-Axis; Y-Axis]** & **[X-Axis; Y-Axis]** & **[kN]** & **[L]** & **[kWh]** \\ \hline Point A \(>\) & & & & & & & & & \\ Point B & 1.53 & 4 & 0.39 & 35 & 75 & [66 kN; 13 kN] & 75.1 & 327.3 & 3174.81 \\ \hline \hline \end{tabular}
\end{table} 
Table 13: Energy consumption for the direct route to the endpoint—Scenario 3. \begin{table}
\begin{tabular}{c c c c c c c c c c} \hline \hline \multirow{2}{*}{**Phase**} & \multirow{2}{*}{**S**} & \multirow{2}{*}{**V**} & \multirow{2}{*}{**t**} & **Course** & **True** & **Conv. Force** & **Sum** & **Fuel** & **Energy** \\  & & & & & & **Wind** & **[X-Axis; Y-Axis]** & **[kN]** & **[L]** & **[kWh]** \\ \hline
34 \(>\) 46 & 0.25 & 4 & 0.064 & 45 & 75 & [54 kN; 14 kN] & 63.5 & 45.4 & 440.38 \\
46 \(>\) 58 & 0.25 & 4 & 0.064 & 45 & 75 & [54 kN; 14 kN] & 63.5 & 45.4 & 440.38 \\
58 \(>\) 70 & 0.25 & 4 & 0.064 & 45 & 75 & [54 kN; 14 kN] & 63.5 & 45.4 & 440.38 \\
70 \(>\) 82 & 0.25 & 4 & 0.064 & 45 & 75 & [54 kN; 14 kN] & 63.5 & 45.4 & 440.38 \\
82 \(>\) 94 & 0.25 & 4 & 0.064 & 45 & 75 & [54 kN; 14 kN] & 63.5 & 45.4 & 440.38 \\
94 \(>\) 104 & 0.25 & 4 & 0.064 & 315 & 75 & [54 kN; 14 kN] & 63.5 & 45.4 & 440.38 \\ \hline \hline \end{tabular}
\end{table} 
Table 14: Energy consumption for the route determined by the algorithm—Scenario 3. This publication also presents a comparison of the ship's passage routes for two cases: a direct route from the starting point to the end point, and the algorithm-determined route. The comparative analysis showed that along the route determined by the algorithm, environmental forces exerted 13% less stress on the ship's hull, resulting in a 7.5% reduction in energy consumption. In addition, three other examples of routes determined by algorithm were presented. In two cases, a 6% reduction in energy consumption was achieved compared to the direct route to the destination, and in one case, environmental conditions were found that allowed a route with a 16% reduction in energy consumption. Theoretically, the presented algorithm has no limitations regarding the maximum length of the determined route, provided that real-time data on wind and ocean currents are available.