Fuel consumption is directly impacted by vessel trim and draught. Consequently, operational costs can be kept low by applying the most fuel-efficient trim and draught for each voyage. The difficulty lies in identifying exactly which values these are. With the installation and utilisation of currently available trim assistant software tools, fuel savings of up to 4-6% can be achieved.

Operational efficiency measures require, above all, changes in behaviour. Simply by changing established procedures, significant energy savings can be achieved without making major investments. Survey results show that lack of knowledge transfer and resistance to change are the biggest hurdles to improving the efficiency of operations. Too little has been done thus far to educate and motivate staff.

Energy saving in day-to-day operations decisively depends on the skill and commitment of crews and onshore staff. A wellplanned training programme supports personnel in obtaining and maintaining the required competencies for effective fuel saving. Typically it also improves communication between ship and shore relating to the vessel's performance. For effective training, both the target group and the objective of the training need to be clear from the very start.

Modern weather routing software products utilise weather, wave and current information as well as hydrodynamic details of the vessel to provide the ship's crew with real-time ship-specific routing advice. A recent study indicated the following cost reducing results from a liner operator's perspective:

Weather routing software tools compare available environmental information (weather, current, wave, ice, tide) with vessel and voyage data in order to provide:

Generally speaking, there are two types of weather routing systems:

Although voyage earnings are fragmented, they are highly dependent on vessel speed, fuel price and freight rates. Simply by adjusting speed, ship owners and operators can potentially increase their operating profits. Despite today's broad awareness of the importance of speed optimisation, software-based tools can still yield significant benefits and help owners and operators to save fuel on a double-digit percentage level.

Fleet performance management solutions utilise operational data to continuously analyse and optimise ship performance. Objectives include the reduction of fuel and machinery-related expenses, as well as the transparency, compliancy and demonstration of efficient and green operations. Supporting tools can significantly reduce staff workload and speed up performance improvements.

Depending on ecological, operational and other conditions, marine growth on both hull and propeller can result in added resistance of over 1% a months. By specifying a matched hull coating system or, alternatively, by regularly cleaning the hull and propeller, significant fuel savings can be realised.

Depending on ship type and operational field, diverse energy saving devices can be mounted to improve water velocity distribution to the propeller and to minimise wake losses due to swirl in the out-flow of the propeller.

Current operating profiles (speed-draught matrix) for many vessels deviate significantly from the profile or design point that determined the initial design of the vessel. Accordingly, the vessel's hull profile is not optimised for current operations. For existing vessels, where the degrees of freedom in hull form optimisation are limited compared to a newbuilding project, retrofitting of the bulbous bow can bring considerable fuel savings.

Changed operational profiles with varying speeds often lead to non-optimal propeller designs on existing vessels. These propellers have typically been designed for maximum speed and low cavitation. An upgrade to a high-efficiency propeller can bring fuel savings of between 2 and 3%.

Auxiliary engines and systems are often designed for extreme ambient conditions or 100% engine load, which rarely occur. The auxiliary systems offer potential for energy consumption reduction

Engine operation at low loads causes turbochargers to operate below their optimal range, limiting the potential fuel oil savings. Additionally, it causes traditional fuel valves to produce carbon deposits in the gas ways, leading to higher maintenance costs. Modifying the engine for speeds as low as 50% of the design speed can prevent mid-term damage and increase combustion efficiency, producing significant fuel savings.

The main engines of many existing vessels were designed for one specific, high vessel speed. De-rating the engine offers the possibility to change the specified maximum continuous rating to lower load points, resulting in higher efficiency with reduced specific fuel oil consumption (SFOC).

Due to upcoming emission targets in the maritime industry, alternative fuels such as LNG are in focus. LNG offers the prospect of up to a 25% reduction in CO2, a nearly complete elimination of sulphur oxides (SOX) and particle emissions, and a 90% reduction in nitrogen oxides (NOX).

In particular a few older designs of containerships offer the possibility to increase numbers of tiers stowed on deck behind the deck house. On some vessels, the deckhouse height is sufficient to allow additional tiers to be loaded, if the visibility line has not been utilized to the maximum before.

Traditionally, wave and wind loading schemes related to container stowage rules have been based on the North Atlantic route conditions. Class-defined formulas were based on the resulting maximum accelerations, limiting container stowage potential for routes in other regions. New, innovative calculation and computation methods allow the identification and exploitation of more flexible container stowage for other routes with better weather conditions. This has led to the new Route Specific Container Stowage class notation.

Existing vessels can be modified to enhance their carrying capacity and deadweight by increasing their draught. The result is more efficient ship operations, especially for traders utilising slow steaming with heavy containers.

Ship operating performance can be enhanced by raising the container stowage capacity on deck.

Some existing vessels have the potential to enhance their carrying capacity, deadweight and contracted project load by lengthening, leading to more efficient ship operations.