Article - April 4, 2019
This trade route is sailed by many ship types including tankers, bulkers and reefers / Ro-Ro’s.
Shown below are three of the many options available.
Clearly shown is a 205 NM savings to the north; however, it has the potential for exposure to bad weather in the northern waters, especially in winter.
A reasonable route might be to follow the northerly route into the mid-latitudes. At that point, if the conditions are looking uninviting to the north a course adjustment towards the English Channel might be considered using the logic mentioned in the SOLAS V Execution section regarding changes in the weather. It can be seen that this route adds only 75 NM to the Channel route, but does afford the possibility of true savings to the north should the conditions allow.
Of course, one might want to consider the speed of the ship. The distance from the point of deviation to northern Scotland is 1510 NM. The 17 knot reefer/Ro-Ro would take 3.7 days to make that leg of the voyage, while the 14 knot tanker might take 4.5 days, and the 12 knot bulker 5.25 days.
Clearly, the faster ship, reefer/ Ro-Ro needs a much smaller window of opportunity to make this run than the slower bulker would need. The two images below, which are just two days apart, show that the northern route would provide a clear savings under the correct circumstances but the results would be very unfavorable during periods of heavy weather.
Heavy weather; the vessel would need to change routes to avoid heavy waves.
Weather two days later when the weather has shifted allowing for the vessel to again take the the shorter route
If starting along the route towards the Channel from the outset, the savings afforded by the northern route would never be realized. Of course, for some ships the northerly route would not be considered an option whatsoever, after taking the nature of the ship and/or cargo into account. For example, the faster reefer/Ro-Ro makes it through the narrow window of opportunity while the time constraint might cause StormGeo to recommend the slower bulker to avoid the northern route all together.
There are certainly other weather patterns and considerations to be thought-through over and above what is depicted here.
StormGeo provides this sort of customized calculation in shore-side weather routing services as well such that the recommended route is customized for the ship type, cargo and speed. As the earlier example showed, through proper route planning in accordance to ship type, cargo and final destination, days can be saved with the optimal route as well as many metric tons of fuel.
“With the onboard software [BVS], the captain can visualize the recommendation made by StormGeo. We believe that this is vital. One thing is to read the route recommendation, another thing is to be able to actually see it and model it in the system by yourself,” said Erik Hjortland, at the time Manager Fleet Performance & Bunkering for Odfjell.
“The combination of the onboard system and the onshore route recommendation is a win-win situation."