Advanced operational measure for reducing fuel consumption onboard ships

Abstract

Environmental issues and targets to reduce greenhouse gas emissions have reinforced attempts to increase energy efficiency for all stakeholders, including the shipping industry. International maritime organization (IMO) has prescribed operational and design measures to develop energy efficiency and decrease ship emissions, and one of the effective operational measures is trim optimization, which is a feasible measure because it does not necessitate ship structural modification or engine advancement, but it can reduce the ship resistance and decrease fuel consumption. The study of trim optimization can be implemented by conducting experimental tests, but it is a difficult, expensive method and consumed more time. Therefore, the present paper proposes a numerical method to predict the optimum trim which achieves the minimum ship resistance and lower fuel consumption. The current paper investigated two types of ships as a case study, bulk carrier, and container ship. The optimization process has studied several trim conditions, ship drafts, and speeds. The results showed that positive trim (trim by bow) have an increasing effect on fuel consumption, while the negative trim (trim by stern) have a decreasing effect on fuel consumption. Fuel-saving based on using optimum trim at each speed is a significant quantity to be benefited as it would reduce the operating costs and increase the energy efficiency.

Review of the IMO Initiatives for Ship Energy Efficiency and Their Implications

“…Optimizing a suitable speed while selecting an efficient propeller is another solution to reduce the fuel consumed, cavitation and noise, particularly when applying engine power limitation level to avoid engine overloading (Tadros et al, 2022d). Optimizing the trim conditions of the ship, so the ship can be trimmed by stern which is more effective than by trim bow in terms of resistance and therefore reduce fuel consumption accompanied by an increase in energy efficiency (Elkafas, 2022). This kind of selection allows the ship master to ensure lower resistance along the route.…”

Thermodynamic Analysis and Economic Assessment of Organic Rankine Cycle Integrated with Thermoelectric Generator Onboard Container Ship

“…The International Maritime Organization (IMO) has developed several laws and guidelines to regulate greenhouse gas (GHG) emissions from ships, intending to reduce these pollutants by almost 30% by 2030 and 80% by 2040 compared to the pollutants produced in 2008 [1,2]. To achieve this goal, numerous operational and technological strategies have been developed to reduce greenhouse gas emissions and increase energy efficiency on board ships [3,4].…”

Environmental economic analysis of speed reduction measure onboard container ships

“…The research displayed that the emissions of ships in port can be reduced by 8.0–11.9% and the traffic efficiency can be improved by 3.8–6.2%. Moreover, the relationship between ship trim, fuel consumption, and the ship speed has been investigated by Elkafas ( 2022 ); the results revealed that the bow trim increases the fuel consumption at different ship speeds while the stern trim decreases the fuel consumption.…”