SERIES 4000 16V ENGINE AND SCR OBTAINS EPA TIER 4 CERTIFICATION

The mtu propulsion system employs a new mtu selective catalytic reduction (SCR) exhaust aftertreatment system to comply with the EPA Tier 4 emission restrictions.

Through further developments in the engines’ turbocharging, combustion process and fuel injection, combined with the new mtu-SCR exhaust aftertreatment system, Rolls-Royce reduced nitrogen oxide (NOx) emissions by 75 percent compared to IMO II requirements and particulate emissions by 65 percent compared to EPA 3, without the use of a diesel particulate filter.

The new propulsion system offers improved fuel consumption, which has been reduced compared with the previous generation of engines (to as low as 190g/kWh). Similar reductions have been achieved in CO2 emissions. The Series 4000 M65L 16-cylinder also offers increased engine power of to 160kW per cylinder for use in heavy-duty workboats.

Rolls-Royce is also working on obtaining EPA Tier 4 approval for additional cylinder variants of the mtu Series 4000 propulsion system and is gradually bringing them to market.

Commenting on the EPA Tier 4 certification, Denise Kurtulus, head of marine business at Rolls-Royce’s Power Systems division said: “This means we have climbed to the king’s class of emissions regulations with our engines for yachts and commercial vessels. I am pleased that we can now offer our customers these clean and powerful propulsion packages.”

Rolls-Royce’s mtu propulsion system, which includes the engines and SCR exhaust aftertreatment, underwent around 10,000 hours of operation in ferries and tugs operated in the U.S. by the San Francisco Water Emergency Transportation Authority (WETA) and Foss Maritime, the largest tug shipping company on the U.S. West Coast. The propulsion system was also subjected to exhaustive test bench runs.

“Thanks to the great cooperation with our customers, we were able to collect the necessary data to reach this milestone. All voyages to date with the total of 10 mtu propulsion systems have been satisfactory. Customers can rely on our engines,” explains Christof von Bank, who is responsible for marine sales in the U.S. at Rolls-Royce.

Foss Maritime has commissioned three of four new tugs with EPA Tier 4-compliant field test mtu propulsion systems while WETA is operating three high-speed ferries in San Francisco Bay with the new mtu propulsion systems.

Since 2018, Rolls-Royce has already been offering the engine Series 4000 propulsion systems with the international IMO III certificate, which also enables operation in special emission control areas (North American coast, Caribbean, North Sea and Baltic Sea).