Efficient ships are inherently more sustainable. As such, to reach sustainability targets, the maritime industry is putting a lot of effort into improving efficiency.
From ship design, construction to operational activities and mid-life retrofits – there are numerous occasions when the subject of efficiency can be tackled. Precise measurements of efficiency strategies are key to presenting their tangible results.
The starting point for Geert Schouten, Director of Shipbuilder, was to provide a clearer picture of the role of sustainability in the shipbuilding industry.
“People are aware of the subject, but do not know how to approach it,” he says.
“Therefore, we have bundled the knowledge that we have about sustainability in a database. This is Shipbuilder’s Sustainability Knowledge Base – an intelligent database that focuses on all the ship’s systems for the whole life cycle of a vessel. From the Requirement Management phase, all the way to end-of-life recycling.”
The database ensures that knowledge about all ship’s systems, with corresponding sustainability rankings, is made available to ship designers and engineers.
“The important part is that each stakeholder in a ship’s life cycle needs to define what his role is in terms of sustainability. Non-competitive sharing of knowledge and data will be the ground-breaker.”
One step at a time
He goes on to say that sustainability is much more of a driving force now because of people’s changing attitudes.
“Of course we had the oil crisis in the 1970’s and that had a major impact on ship design philosophy. But today sustainability is an enormously broad term. If a shipowner switches from heavy fuel oil to LNG, is this sustainable? Yes, it is a better alternative, but it is not the ultimate step in terms of sustainability. The point here is that sustainability will be achieved in a step-by-step process. Firstly because ships have a 30-year life cycle. Secondly because of technological limitations. And thirdly because people’s attitudes change with time.”
According to Schouten, the government also plays an important role in promoting sustainability: “Shipowners will always prefer the sustainable option if the finances are available. Here the total cost of ownership and financing are key aspects. For example, governments have made it more attractive to own electric cars and this has promoted the electric car industry. If we want the Dutch shipbuilding industry to build more sustainable ships – something that definitely will give a competitive advantage – then the government has to stimulate this.”
Finding the benchmark
When discussing how shipowners can improve a vessel’s efficiency (and therefore become more sustainable), there are some key steps that need to be taken.
Dan Veen, CEO at We4Sea, echoes Schouten’s comment that many shipping companies are aware of the subject of sustainability but adds that most of them do not know what their current situation is. He says that, in order to improve, owners need to know about their current performance.
“Informing shipowners of energy efficiency and fuel use is part of what we do – providing them with a benchmark starting point. The critical issue here is that shipping is a very dynamic business: ships sail different routes, with different cargos and with different fuels. We also include the weather as a determining factor as this has a very large influence on the performance and energy use of a ship – in fact, to achieve real sustainability you have to incorporate all these factors. With our dashboard, shipowners can see the performance of their ships 24/7. These results on fuel use, and therefore CO2, can then be compared to a company’s own sustainability goals,” Veen says.
“The second step is to compare a ship’s current performance with its intended design performance. This is because, in real-life operations, there are many factors which can be different from the design. The bigger the difference between current and design performance, the lower the efficiency of components such as engines and propellers is, and the more room for improvement there is.”
This is followed by vessel optimisation, according to Veen: “Tugs illustrate this well. They are designed to deliver a large amount of power, but only for a minimal amount of time. For most of the time, a tug is transiting from A to B or waiting between jobs. Therefore, maybe a better solution is to be a little less efficient during towing operations and more efficient during transiting and idling.”
The final and possibly the most crucial step carried out by We4Sea is to calculate the effect that certain operational adjustments can have on efficiency.
“This allows ship owners to make more informed decisions about retrofits. This can involve various ship systems like propeller modifications, change of fuel, adjustment of engine RPM or new hull coatings. We have a recent example of an electro-technical conversion that resulted in a 13 per cent reduction in fuel use for the client,” Veen states.
Because every ship is different, the accurate analysis of data will be vital to providing the best advice.
Veen concludes: “To learn what the optimal situation is for each ship for parameters such as speed, optimal propeller pitch or route planning, data analysis will play a bigger and bigger role in the future.”
Raw data can be provided by various on-board sensors and instrumentation. While fuel flow meters measure fuel consumption, and therefore emissions, shipowners need deeper insight into ship efficiency, Erik van Ballegooijen, Technical Consultant Hydrodynamics with VAF Instruments, says.
Providing this detail is what the company’s products set out to accomplish. TT-Sense, for example, uses optical sensors placed on the propeller shaft to measure inefficiencies.
“Variations in torque are measured by prop shaft torsion and propeller thrust variations are measured by prop shaft compression.”
Because the field of thrust measurement is relatively new, Van Ballegooijen notes, clients still need a lot of awareness about the benefits that include environmental, maintenance, fuel saving and financial aspects.
“For example, many shipowners don’t know that it enables savings on fuel and maintenance costs of up to 20 per cent.”
Considering the recent changes in IMO and European monitoring guidelines, such fuel savings become more relevant.
Managing the data
Van Ballegooijen says that thrust measurement will play an increasingly important role in the future: “The subject will only get broader – with more and more sensors on board increasing our knowledge of performance. Measurements are one thing – they are primarily obligatory due to regulations. But once you have collected 1 TB of data from sensors, what then? You need to analyse the data to enable improvements. It is these improvements that will give owners the competitive advantage.”
Obviously, manual analysis of Big Data is unfeasible. “This asks for clever automatic data enrichment and analysis solutions like IVY,” he adds, referring to VAF Instruments’ propulsion performance management solution that won the Energy Efficiency Solution Award last year.
“Taking hard data from sensors, IVY is a system that bridges the gap between sensor data and decision-making. For instance, propellers can deteriorate and a hull can have increased resistance over time. Powerful analysis on hull and propeller performance provides important input to the fuel saving and maintenance investment decisions, by answering the following questions: How can I improve efficiency? And how can I improve maintenance?”
Keep up to date
The relationship between monitoring vessel efficiency and sustainability still has a considerable way to go. It is a broad subject that affects single vessels and entire fleets. It makes itself known from the preliminary design phase, during the operational lifetime up until the end-of-life. And don’t forget: improvements in efficiency (and therefore sustainability) are likely to have a positive financial knock-on effect. It is in our interests to be well informed.
This article was previously published in Maritime Holland edition #1– 2017.