Marine Merchant vessels


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Wärtsilä provides environmentally and economically sound integrated solutions for powering ships. In so doing we add value to the businesses of ship owners and operators around the world.

Our Merchant business has a professional focus, not only on power and propulsion, but also on maintaining and operating seaborne transportation in more economical and sustainable ways.

The world’s merchant fleet represents almost 80% of all the vessels ordered each year. Of these, 85% are powered by two-stroke engines and the remainder by four-stroke engines. With the environment and fuel economy likely to be the future market drivers Wärtsilä is positioned as the most suitable systems provider for extended ship power solutions. Our Merchant sales and service network provides a unique, competitive offering that is based on a deep understanding of our customers’ businesses, and which generates solutions that help them to achieve their business goals.

Wärtsilä follows and supports its customers’ projects throughout the life cycle of the installation. Through early involvement and long-term commitment, we provide everything from ship design and a comprehensive product portfolio, to integrated solutions and lifelong after-sales support.

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    Tankers currently represent 27% of the world’s merchant fleet larger than 2000 grt. They carry a variety of liquid cargoes in bulk, such as crude oil, products and chemicals.

    In most of cases, the voyages are long, fuel consumption is usually the main focus of the solution that Wärtsilä can propose. The standard machinery solution is reliable, simple, safe and economical, with a two-stroke engine connected to a single shaft line. The RT-flex common-rail system in Wärtsilä two-stroke engines has built-in redundancy. This eliminates unexpected engine stops and introduces the highest level of flexibility for engine tuning. The benefits of machinery reliability can also be enhanced through the Condition-Based Maintenance (CBM) service delivered by Wärtsilä. This aims to provide extended intervals between overhauls and improved operating profits. For increased machinery efficiency, waste heat recovery (WHR) can be selected.

    Wärtsilä Ship Design also supports its customers’ businesses with environmentally and economically optimal solutions, such as original designs for product tankers.

    Vessel Type Size
    ULCC, ultra large crude carrier > 350,000 dwt
    VLCC , very large crude carrier 250,000-325,000 dwt
    Suezmax 125,000-170,000 dwt
    Aframax 80,000-120,000 dwt
    Panamax 60,000-80,000 dwt
    Handymax 40,000-60,000 dwt
    Handy 10,000-40,000 dwt
    Small < 10,000 dwt

    Bulk Carriers

    Today, bulk carriers make up 21% of the world’s merchant fleet. Wärtsilä has a range of low-speed engines that successfully power all types and sizes of bulk carriers. At the top of the Wärtsilä range are the high power Wärtsilä RT-flex82T engines, while the new small-bore low-speed engines, the Wärtsilä X35 and Wärtsilä X40, are for lower engine power.

    Ship owners, operators and yards are able to benefit from low running costs, reliability and easy installation provided by Wärtsilä engines, and from the support provided throughout the entire life cycle of the equipment. With ease of operation, the Wärtsilä engines require minimal operator training, a factor that is particularly helpful when changing crews.

    Container Vessels

    Container vessels form 13–14% of the world’s merchant fleet and are a vital element within the transportation infrastructure supporting the global economy. Machinery reliability is, therefore, essential.

    Wärtsilä serves its container vessel customers with integrated solutions that offer significant cost savings. High energy efficiency has the greatest impact on operating costs and is delivered by solutions from Wärtsilä which combine an engine with low fuel consumption, high-efficiency waste heat recovery (WHR) system, and optimum propeller and rudder designs. One of the largest two-stroke engines, the 14RT-flex96C, has been sailing for years with a WHR system bringing important savings to the ship operators.
    Original ship concepts presented by Wärtsilä Ship Design show how container vessels can be designed to take advantage of the new Panama Canal dimensions. The fuel efficiency gain is driving the Wärtsilä proposal to the customers for example through WHR , Delta Tuning and Low-Load Tuning.
    Container ships can be categorized according to their TEU capacity and hull dimensions as follow.

    Vessel Type Size
    ULCV, Ultra large container vessel above 10000 TEU
    Post-Panamax 5000-10000 TEU
    Panamax 3000-5000 TEU
    Feedermax 2000-3000 TEU
    Feeder 1000-2000 TEU
    Small feeder below 1000 TEU

    Wärtsilä offers designs for container vessels in many different size classes.

    Delta Tuning
    In case the operational profile of the vessel changes with a new charter contract and allows a lower speed, Wärtsilä can propose an easily reversible solution to save fuel by adopting the Delta Tuning for the RT-flex engines.
    By allowing injection pressures and timing to be optimised at all loads, Wärtsilä RT-flex engines have lower fuel consumption at part loads compared with conventional camshaft-type engines. Advantage has been taken of the complete flexibility in fuel injection and valve operation allowed by RT-flex common-rail technology to offer, through Delta Tuning, even lower specific fuel consumption when running at less than 90% engine load.

    Low-Load Tuning
    The most effective way to achieve fuel savings is to reduce the ship speed. When this is planned to be adopted for a long time, Wärtsilä can propose the Low-Load Tuning package which allows RT-flex engines to be tuned for the best fuel efficiency at partial load. This can also be retrofitted on existing vessels.
    Reduced part-load fuel consumption is offered by Low-Load Tuning through a package of measures for RT-flex low-speed engines:

    • Part-load optimised turbochargers
    • Increased combustion pressure at less than 75% MCR
    • Late exhaust valve closing to reduce NOX emissions
    • Exhaust waste gate opening at 85% MCR

    Cargo Vessels

    Cargo vessels represent 25–30% of the world’s merchant fleet. The latest general cargo vessels tend to be for specialised applications, such as multipurpose carrier (MPP).

    Whatever the vessel’s operating profile, Wärtsilä offers customized solutions that meet the specific needs of ship owners and operators. Wärtsilä innovative approach and broad product portfolio enable fit-for-purpose cargo vessels to have the flexibility needed to achieve clear environmental and economic benefits.

    The ability of Wärtsilä to combine products into a single solution package that combines engines, gearboxes, automation, alarm monitoring, propulsion control, and more, provides guaranteed performance of the complete installation, uniform documentation, a single point of contact, and an efficient propulsion plant in which all parts are engineered to work in harmony.

    The result is a simple to install, pre-engineered solution that reduces shipbuilding errors, and which is supported by world-wide after-sales service.

    Ro-Ro/PCTC Vessels

    Ro-Ro vessels are designed to transport wheel-based cargo or cargo loaded on wheel-based equipment. Frequent port calls mean that emissions must be minimized, while the efficient loading and unloading of the ship is a primary requirement.

    Ro-Ro vessels typically operate on short trades with frequent port calls. Most are equipped with thrusters, twin screws and a geared, multiple diesel engine installation to provide the flexibility needed. Their operating profile shows that some 36% of these vessels spend more than 80% of their time in ECA (Emission Control Area). To help meet environmental legislation, Wärtsilä offers a complete diesel-electric solution involving dual-fuel engines, as well as a full gas-fuelled system.

    PCTC (Pure car/truck carrier) vessels are purpose built for the transportation of different types of rolling cargo. The essential requirement is that the machinery installation occupies the minimum space to maximize cargo space and facilitate cargo handling. Within those restrictions, the machinery solution must also have the lowest possible fuel consumption and least environmental impact. The Wärtsilä Energopac is specifically designed to reduce the propulsion power requirement.

    A power management system, including the Low-Loss Concept (LLC) reduces electrical losses by 33%, and the entire vessel can be optimized to suit each operational profile. In combination with LNGPac and dual-fuel generating sets or main propulsion, LLC also represents an environmentally compatible solution. The diesel-electric know-how of Wärtsilä helps greatly in ship design and the development of concepts for the future.

    Gas Carriers

    The combination of Wärtsilä’s proven dual-fuel engine technology and electric propulsion systems has produced an LNG carrier machinery solution that offers significant benefits over alternative concepts.

    Wärtsilä’s dual-fuel-electric machinery solution provides industry-leading benefits, including environmental compatibility, reliability, redundancy, maintainability, and fuel flexibility, as well as operating economy and safety. They are available in a power range of 0.8–17.5 MW with speeds of 500–1200 rpm.

    The environmental aspects of dual-fuel engine technology are extremely beneficial. The solution is very clean and reliable with a high efficiency. There are no visible smoke emissions and no sludge deposits. The low-pressure gas system is safe and simple to operate.

    The use of heavy fuel oil for the DF engines in‘diesel mode’ further enhances their fuel flexibility, and provides ship operators with the highest degree of control over operating costs when gas and liquid fuel prices fluctuate.

    Wärtsilä’s dual-fuel technology means that engines do not need to be stopped and do not lose power or speed when changing fuel type. Our Merchant team is available to advise on the most suitable solution for specific applications.


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