Wärtsilä’s 2-stroke dual-fuel engine introduced

Wärtsilä Corporation, News 20 November 2013 at 11:00 UTC+2

The marine industry is already showing significant interest in the new Wärtsilä 2-stroke, low-speed, dual-fuel (DF) engine technology. More than 130 industry executives from 89 leading shipping companies attended the introductory event in Trieste, Italy on November 12, which is in itself a clear indication that there is global recognition of the role that LNG fuel will play over the coming years.

The significance of the new Wärtsilä technology is that the low pressure, dual-fuel benefits that are already available to 4-stroke engines, can now be applied to 2-stroke engines as well. Phrases like ‘game-changing’, ‘gas revolution’ and ‘a paradigm shift’ were used at the event to describe the introduction of the new engine. This is hardly surprising since it means that this technology is now available to the broader merchant shipping market, along with the dual economic and environmental advantages that it offers.

On the environmental side, the overwhelmingly important benefit is that Wärtsilä’s unique low pressure DF engine is NOx compliant with the IMO’s Tier III regulations without secondary measures. There are no sulphur emissions and close to zero particulate emissions, while the pilot fuel consumption is extremely low at just one per cent of the fuel used. Furthermore, the technology enables LNG fuel to be used at all engine loads, so there is no need to switch to diesel at low loads – when manoeuvring or in port – as is the case with other DF technologies. This has an obvious impact on the vessel’s exhaust emissions, as well as on operating costs.

In addition to the environmental benefits, there are also related economic advantages. The primary advantage is that because in gas mode these engines are Tier III compliant, there are no investments needed in exhaust gas cleaning systems. Additionally, with Wärtsilä’s technology, the LNG gas handling system is far simpler and less expensive than that of alternative technologies.

Compared to other technologies, studies show that Wärtsilä’s low pressure DF engines offer capital expenditure (CAPEX) reductions of 15-20 per cent. Thus, the low pressure gas engine and its associated systems deliver the smallest ecological footprint, with less consumption of energy and resources, and the least production of emissions.

Customer reactions to the new technology appear to be extremely positive. For example, Pontus Berg, General Manager of Greenship Gas, said; “This offers an attractive option for all ships, not just LNG carriers. The market has been waiting for a simpler solution than that provided by high pressure DF technology because high pressure systems demand specialised crew training, whereas Wärtsilä’s low pressure engines seem easier to operate.”

Martin von Sydow, Vice President Ship Design for Wallenius Marine AB, was equally upbeat. “LNG is definitely the most attractive alternative fuel today and it fits well our company policy. Wärtsilä’s low pressure DF technology for 2-stroke engines will be very welcomed by the industry – the number of people at this event shows how important it is. We definitely have something to think about when making future purchasing decisions.”

Because of the number of attendees at the customer event, there was not room in the test facility for everyone to see the engine operating. Instead, they watched by video feed from the auditorium. It was particularly impressive to witness the smooth switch from diesel to LNG operation and to see the dramatic fall in NOx emissions as this change took place. At the subsequent Q & A session a variety of issues were covered, including safety, bunkering, and the key technologies. It was emphasised, however, that the technology has already been proven over many years with the company’s 4-stroke, medium-speed DF engines. The real significance is that the test engine, the Wärtsilä RT-flex50DF, is the first low-speed engine optimised to operate on gas fuel that has been introduced to the market.

The on-going development of the LNG supply infrastructure was again emphasised with the recent LNG bunkering accord between the ports of Singapore, Antwerp, and Zeebrugge as a means of facilitating the use of gas as a marine fuel.

In his opening speech at the Trieste event, Jaakko Eskola, Senior Executive Vice President and President, Wärtsilä Ship Power, stated: “Dual-fuel engine technology is the future; it is a tide that cannot be turned back. Gas is certain to play an increasingly important role in merchant shipping - for both economic and environmental reasons. The introduction of Wärtsilä’s 2-stroke, dual-fuel, low-speed engines is a historic landmark in this process.”

The entire portfolio of Wärtsilä 2-stroke engines will be available as low pressure dual-fuel versions. The first engine utilising this technology, the Wärtsilä RT-flex50DF, will be available for delivery in the third quarter of 2014. Other engines from the company's new Generation X series will follow and will be available for delivery during 2015 and 2016.

Media representatives from seven countries attended the event in Trieste. A factory tour was part of the programme.