Last Updated: Apr 2012
According to a Norwegian Marine Technology Research Institute MARINTEK study, operational planning and speed selection have the potential to save up to 40% carbon emissions.
The IMO's study of Greenhouse Gas emissions from Ships, added that vessels can potentially save about 2-4% in fuel by using weather routing. The estimated potential of weather routing on the world's fleet is a reduction in CO2 emissions of 0.8%.
In April, 2012 sea trials by Tidetech confirmed that ocean currents can help ship operators cut fuel costs by up to 4%.
Weather routing specialists Applied Weather Technology Inc. say that if every vessel used its software it would have the potential to save over $180 million per year and reduce CO2 emissions by approximately 1,400,000 metric tonnes annually. In September 2010 AWT said that its studies have shown fleets have realised fuel savings of between 5 and 10% using the BonVoyage System (BVS).
"Weather routing can result in substantial savings for ships on certain routes. However, weather routing systems are not uncommon, and the incremental saving that can be expected from improvements in such systems and from their more widespread use has not been assessed," according to the IMO Second Greenhouse Gas study.
The potential for just-in-time arrival has been assessed at 1-5% in the 2000 IMOs study More recently, the potential for energy saving by just-in-time arrival has been estimated to be 1% based on the Japanese domestic fleet.
According to the IMO, software systems must be used and understood, and the skills and motivation of the crew are critical.
While there may be many opportunities to optimise and improve operational efficiency at some level, doing so requires the cooperation of several parties, especially in cases where ships are operated by a different company than the commercial operator, the technical operator may tend to minimise time in dry dock (to minimise off-hire cost) and other maintenance costs while at the same time handing the fuel bill to the commercial operator.
In another example, a ship operator may arrive in a busy harbour, only to wait for days or weeks to unload, while receiving compensation (demurrage) for each day of waiting, according to the IMO study.
The IMO's ship energy efficiency management plan (SEEMP), which is being developed by the Marine Environmental Protection Committee, focusses on, among other things, weather routing systems and virtual arrival.