SOLUTION 01 / Environmental Load Reducing

Cleaner emission and more power, the marine engine using in combination with both diesel and gas fuel.

Large Power Products Management Division, Power Solution Business
From the perspective of global environmental protection, emission regulations have been stricter in the marine world, and reduction of environmental pollutants such as NOx and SOx has become a challenge. To reduce environmental impacts, Yanmar has developed a dual fuel engine that can switch between diesel and natural gas fuel (LNG). The installation of Dual Fuel Engines on tugboats and other are increasing.


Engines that consider global environment and operate with high economic efficiency

Large vessels operating in the seas around the world are equipped with engines with high power. An issue confronting our world today is the air pollutants from the emission of those large engines. In recent years, the use of natural gas has attracted attention. Liquefied natural gas (LNG) is environmentally friendly and can reduce greenhouse gases. Therefore, Yanmar has begun developing the dual-fuel engine that can flexibly use both LNG and diesel fuel to take advantage of eco-friendliness and wider availability. We set the goal high to develop a new engine complying with The International Marine Organization (IMO) Tier 3 NOx (IMO3) and SOx regulations for all sea areas based on a reliable model that can pursue improvements in the life cycle value (LCV) for customers.

Effective since January 1, 2016, the 3rd tier regulation (IMO3) is that IMO requires on the standard of NOx emission control. IMO3 to regulate 80% lower emissions than the primary regulation, is applied within a designated sea area called NOx Emission Control Area (N-ECA). The US and Canadian coasts, the U.S. Caribbean, the North Sea and the Baltic Sea have already been regulated for SOx, while the U.S. and Canadian coasts have already been regulated for NOx. The North Sea and the Baltic Sea will be subject to regulation from January 1, 2021.


Realizing safe and stable navigation with Yanmar technology

Yanmar developed the dual fuel engine incorporates highly accurate air flow control technology. Maintaining the optimum combustion condition at all times, it makes the operation more reliable and stable while using both gas and diesel fuel. In addition, an unique control system has been adopted to ensure safety during operation in the world sea. By multiplexing the devices, we achieved safety and redundancy that enable safe navigation with only one machine per axis. Furthermore, it is equipped with its own air-fuel ratio control and knocking detection system. Even when using natural gas fuel with low methane number, which is concerned about abnormal combustion (knocking), cylinder pressure is analyzed in real time. With the high-speed control, it can avoid knocking. Dual Fuel engine is compatible with natural gas from all over the world and can be operated without power restrictions. During navigation, it is possible to switch from diesel mode to gas mode even at maximum output. In case of an emergency, it switch from gas mode to diesel mode safely and instantaneously.


Compatible with strict environmental regulations

In the gas mode of the developed model, 6EY26DF, we achieved approximately 80% of NOx (nitrogen oxide) , 25% of CO2, 99% of SOx (sulfur oxide) and PM (particulate matter) reduction compared to our previous model in the same engine class, 6EY26W. Meeting the 3rd tier IMO standard while maintaining its advantages such as high fuel efficiency and power, we created new technologies that address the global issues of reducing environmental impacts and fluctuating fuel prices. Yanmar has been driving the evolution of engines, and will continue to diversify technologies for the next generation.

INTERVIEWInstalled on Ishin,
Connecting people to be a drive force of the project

The tugboat, Ishin has been engaged in security work for large cargo ships navigating Osaka Bay and the Seto Inland Sea, and towing port entry and departure since March 2019. It is drawing attention as the first tugboat in Japan that uses liquefied natural gas as fuel and meets the IGF Code (*) standards. Yanmar's dual fuel engine, 6EY26DF is installed as the main propulsion engine for the "Ishin".

A tugboat and its characteristic work can put sudden and heavy loads on the engine due to pushing and pulling a much larger and heavier ship or cargo. Doui, the person in charge of the testing, looks back and says “Yanmar has no history producing gas engines for a marine product, and the gas mode in general has vulnerability to load fluctuations. As a first product to deliver, I felt that the project was going to be really difficult.” "At meetings with the partners involved, we were asked if it would be ok to proceed and told that they cannot use a tugboat if they did not meet the standards. Even with some harsh words, we worked together to meet the expectations and kept solving problems,'’ says Mr. Doi and Mr. Kubo, System Design Manager. Nishimura, who is in charge of engine design, says, "We thoroughly evaluated the safety aspects so that the crew could use the gas mode in peace, as well as the environment."

At the first to set sail, the members of service division as well as the development division boarded the tugboat. Each joint partners praised that the feeling of unity was building as the boat came in shape. That was the pure joy and impressive work. The project was realized by the joint promotion of the customer and Yanmar.

* IGF code: International code of safety for ship using gases or other low-flash-point fuels issued in 2017 to specify safety requirements.