Page 36: of Marine News Magazine (March 2020)

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EMISSIONS COMPLIANCE

Photo: Cummins

Boyer Towing recently repowered its 1997-built tug Gretchen H three new Cummins

QSK19 Tier 3 compliant engines rated for 750 HP each at 1,800 RPM.

Tier 4, of course, doesn’t apply just to new vessels. A EPA’s regs were ? nalized in 2008 and Tier 4 phase in was vessel owner seeking to repower an older vessel confronts supposed to have concluded by 2017. This uncertainty the same long list of questions and trade-offs. He or she impacts decisions across the board – at shipyards, among may decide it’s easier just to avoid the whole set of issues engine manufacturers and vessel owners.

and instead of buying one Tier 4 engine at 800 HP (the Last September, EPA proposed to delay Tier 4 imple- 800 HP Tier 4 threshold, also 600 kW) he or she may mentation for certain types of vessels – high powered ves- purchase two smaller engines instead. And increasingly, sels such as lobster boats. In response, comments came in hybrid applications, using electric and diesel power gen- from across the industry imploring EPA to expand the eration are drawing operators’ attention. Hybrid systems scope of that delay – to include a broader range of vessels, double-up, when needed, to deliver maximum power un- from workboats to tour boats. EPA’s public comment pe- der load, and maximum load is usually just a fraction of a riod ended in October. However, behind the scenes, EPA vessel’s operating time. has maintained an active and pointed discussion with in-

To make matters more complicated, the Tier 4 market dustry reps, asking for their perspective on the charges and and business milieu remains shaky. Tier 4 decisions sit countercharges within the Tier 4 debate. The many issues within an unsettled regulatory environment – even though with Tier 4 compliance remain hotly contentious.

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