A Tier 3 Milestone

Wärtsilä said its 34DF dual-fuel engine achieved U.S. Environmental Protection Agency’s (EPA) Tier 3 certification for diesel mode operation when installed together with the Wärtsilä NO_x Reducer (NOR) system.

The Wärtsilä NOR is a selective catalytic reduction (SCR) system that converts nitrogen oxides (NO_x) with the aid of a catalyst into diatomic nitrogen (N2) and water. Wärtsilä said it is the first engine manufacturer to be awarded this certification.

The benefit of this award is that shipyards now need only a single party to certify both the engine and the SCR system for full compliance with the latest emission regulations. The Wärtsilä 34DF has already been awarded EPA Tier 3 certification of emissions compliance from the EPA in 2017 for operating in gas mode without an SCR system.

“This is a very meaningful achievement since it allows operators complete fuel flexibility when sailing in NOx emission control areas. It represents further validation of Wärtsilä’s technological leadership in working towards greater environmental sustainability and a cleaner shipping industry,” said Stefan Wiik, vice president, Marine Power Solutions, Wärtsilä Marine Solutions.

The US EPA Tier 3 NO_x requirements entered into force in 2016 for Category 3 engine sizes (engines with a cylinder displacement at or above 30 L/cylinder) to be installed in U.S. flagged or registered vessels.

At the same time, the International Maritime Organization’s (IMO) NOx Tier 3 requirements also entered into force in North American and U.S. Caribbean emission control areas (ECAs) from January 2016 for vessels with a keel-laying date on or after January 1, 2016 and an engine output of 130kW or more.

The Wärtsilä 34DF engine is now certified for both the EPA Tier 3 and the IMO Tier 3 emission standards in diesel mode operation when installed together with the Wärtsilä NOx Reducer SCR system, as well as in gas mode without exhaust after-treatment.

The 34DF engine incorporates advanced dual-fuel technology and high efficiency. For marine applications, it is manufactured in configurations from 6 to 16 cylinders covering a power range of 2880 to 8000 kW. Based on the Wärtsilä 32 diesel engine introduced in the mid-1990s, the Wärtsilä 34DF’s fuel flexibility means that the engine can be optimized for constant speed generating sets, as well as variable speed mechanical drives for main engine applications, the company said.