Page 34: of Marine News Magazine (March 2020)

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EMISSIONS COMPLIANCE

TIER 4 –

Di? cult and

Contentious, 12 Years and Counting… © JinnaritT / Adobe Stock

By Tom Ewing hen it comes to complying with EPA’s Tier 4 working to ? t the hardware and related components inside emissions regulations, there’s no shortage of cre- a hull. Tier 4 demands are rigorous: emissions from 25 Tier

Wativity emerging from America’s maritime engi- 4 engines are supposed to be equivalent to just one Tier 1 neering ? rms. Companies such as Hug Engineering are engine. The vessel, its engine and the aftertreatment need offering ? exible, customized aftertreatment-based control to function as a single system for optimal performance, systems that can assemble almost in modular like fashion. reliability, cost and emissions reduction.

Other companies, such as ABB Group, offer battery-hy- From discussions with experts in the Tier 4 ? eld, some brid power sources to complement combustion power and of the Tier 4 installation technical challenges are being avoid threshold diesel emissions. Engine manufacturers, met. Progress is slow but new vessels, at least, are being de- such as Cummins, are working with aftertreatment sup- signed to incorporate Tier 4 engines and the aftertreatment pliers to ensure operational harmony between power plant systems which, of course, require as much room as the en- and pollution controls. Scania AB is demonstrating new gines to which each unit must be linked. (See diagram.) successes by approaching power from a systems standpoint, Importantly, though, these advances must spread out taking a close look at a vessel’s actual power demands and across a very fractured landscape. Progress with one vessel how and when that power needs to be delivered. or application doesn’t mean success elsewhere. Each differ-

As vessel owners know, this is not easy stuff – in any way. ent class of vessel requires a different approach and analysis

Tier 4 systems are complex and expensive, to purchase and to Tier 4 implementation, lobster boats are not the same operate. They are big, frequently requiring customized, as ferries which are not the same as pilot boats. It’s not an speci? c analyses for placement within a vessel; a challenge exaggeration to write that every vessel – not just every ves- and dif? culty that EPA refers to as “packaging,” literally sel class – demands its own analysis.

March 2020 34 MN