Vessel Optimization to reduce emmission

This article provides a background for evaluating the potential impact of commercial shipping on global warming, and explains current methods used to estimate its contribution of greenhouse gas (GHG). The relative severity of various exhaust components is discussed, as well as means that are available for controlling them. For example, for each ton of bunker fuel consumed by the ship, approximately 3 tons of carbon dioxide (CO2) is emitted into the atmosphere.

Ongoing monitoring of fuel consumption by each type of ship (bulk carrier, oil tanker, general cargo, container, etc.) will help us determine where to focus our attention for the greatest benefit. A web based application program called, Blue Water Optimum Speed services (BOSS) incorporates advanced voyage optimisation algorithms that take into account the ship’s hull design, propulsion system, and sea keeping models, as well as user-defined speed/RPM. Using this service , voyage operator can plan and execute a voyage that takes advantage of the ambient ocean conditions through optimal speed. In doing so, significant reductions in fuel consumption and GHG emission are possible without increasing voyage duration/ETA.

BOSS demonstrate how potential savings can vary with the location of the passage, the direction between ports, the overall distance, time of year, type of vessel, and flexibility of schedule. Other important variables include cargo load displacement, ballast, trim, and fuel quality initially, a ship’s index can be estimated by simulating past voyages using known performance parameters, voyage data logs, and a historical database of ocean weather. Later, these parameters can be adjusted by continually monitoring and recording actual ship performance and voyage data, and by conducting post-voyage analyses. In this way, any lost efficiency, for example, from increased hull or propeller roughness, malfunctioning engines, or other causes, can be promptly detected, and its effect on fuel consumption evaluated. Ship maintenance can be scheduled using real performance data rather than an arbitrary period based on past experience. Performance monitoring may also be used to fine-tune BOSS in a real-time adaptive learning process. Commercial ship engines burn distillate or residual diesel fuel called “bunker fuel”. This low grade fuel, also known as No. 5 or No. 6 fuel oil, is highly viscous, needing to be preheated before it can be pumped, and is typically high in pollutants, especially sulphur. It is, in fact, the cheapest liquid fuel available.

Maritime shipping, which emits approximately 4% of the world’s total GHG, is one of the lowest contributors of GHG among commercial transportation methods. Nonetheless, it remains a substantial source of emissions of carbon dioxide (CO2), nitrogen oxides (NOx), sulphur dioxide (SO2), and particulate matter (PM). Until recently, ship-generated NOx was the greatest concern for policy-makers because it is a major source of localised air pollution around coastal and port cities. However, policies intended to address global climate change must encompass a broader range of emissions, including CO2, SO2, and PM. Furthermore, it is increasingly evident that the impact on global warming from emissions of carbon, a normal product of bunker fuel combustion, may be greatly underestimated.

 EFFECTIVE METHODS OF REDUCING EMISSIONS

Emissions are directly proportional to fuel consumption. It is clear that an effective means to reduce emissions is to reduce fuel consumption. As an added benefit, reduced fuel consumption will reduce cost, an increasingly critical factor in the economic equation for commercial shipping

The overall speed reduction of 10% would result in a 23% reduction of CO2 emissions. Slowing even more to 20% should reduce CO2 by close to 50%. This is because bunker fuel consumption by a ship’s main engines can be empirically shown to be proportional to the third power of the velocity, which in actual practice has proven to be a good approximation.

 WHAT IS  BOSS VOYAGE OPTIMISATION

 A simple mandate to reduce speed would be a very difficult to comprehend in commercial shipping industry, whose economics depend in part on fast transit times. Furthermore, because of the tight logistics of modern ports and connecting ground transportation, a ship arriving late can result in significant additional costs, effectively negating any savings made in fuel consumption. Therefore, a common strategy of operation is to run at high speed, conditions permitting, for the majority of the passage, and then slow down for the final leg to ensure arrival at the allocated time. This is likely to result in a worst-case scenario from the point of view of fuel consumption.

 Blue Water optimum speed services (BOSS) offers intelligent speed simulation tool that can significantly reduce fuel consumption and associated emissions while maintaining the same overall transit time. In a program developed by a team of engineers led by Capt. Kumaresh Gupta, a ship’s speed and route can be optimized based on the wind, waves, and currents, taking into account the ship’s performance criteria such as hull shape, horsepower, load, trim, ballast, pitch and roll limits, and other factors.

The BOSS software incorporates advanced voyage optimisation algorithms that include the ship’s hull design, propulsion systems, and sea keeping models, as well as user-defined safe operating limits. The software then calculates the time of passage and fuel consumption, optimising the ship’s route and velocity to suit the ambient ocean conditions while observing the specified schedule and the ship’s performance and safe operating limits. If an envelope of routes is specified, the software can find the optimum one, and exclude any that exceed specified limits.

In this analysis, each possible route segment is examined for optimum speed resulting in an on-time arrival and minimum fuel consumption while observing ship performance and safe operating limits. 

“Ship handling is an art of controlling factors beyond control, by controlling factors which are under control”.

BOSS is inspired by this famous saying. It manages main engine RPM intelligently to exploit factors beyond control i.e., weather and market. BOSS uses enhanced data mining techniques and marine hydrodynamics functions to derive intelligence from completed voyage data and vessel test results. Advance algorithms are then applied for simulating the voyage in forecast/historical weather, taking into consideration all such factors that can affect voyage earnings, such as ETA at charter party speed, ETB, Freight, Demurrage, Bunker rates and even the Inventory cost.

The salient features of this service are:-

• Online access to the system by ship-owner, charterer, cargo owner, terminal and other stakeholders as per client requirement.
• Continuous monitoring, observation and recommendation by BOSS voyage analysts.
• Add-on service like Interactive Negotiation Tool, Speed - Fuel Consumption Calculator, Speed-RPM-FOC Curves and Voyage Plan Comparator (for comparison of voyage earnings/TCE)
• Vessel Performance Curves- to view and analyze the trend of vessel’s M/E performance.

“This service does not require any retrofitting and installation of software or hardware and hence is a zero investment product as,” explained Blue Water founder and managing director Captain Kumaresh Gupta.” BOSS is an online secured practical process that aims at an operational optimisation through collective & informed decision; the direct benefits of which may be verified almost immediately.