Ask people what upcoming date might most affect their lives over the next several years, and the answer could well be Nov. 8, when either Donald or Hillary is elected president. Ask a boatbuilder or naval architect that question and if they tell you Nov. 8, it should quickly be followed by “Oh. Yeah, and January 1.”

A Cummins Tier 4 engine. Tier 4 is designed to deliver a 90 percent reduction in particulate matter and an 80 percent drop in nitrogen oxides, compared to the previous Tier-2 requirements. Cummins photo.Not because it’s New Year’s Day. No, Jan. 1 is when boatbuilders and naval architects have to officially start dealing with Tier-4 air emission regulations, which apply to engines over 804 horsepower. Tier 4 is designed to deliver a 90 percent reduction in particulate matter and an 80 percent drop in nitrogen oxides, compared to the previous Tier-2 requirements.

Most engine manufacturers will use a urea-based selective catalytic reduction exhaust after-treatment system to reduce nitrogen oxide emissions. The SCR system adds urea to exhaust gases that then go through a catalyst, leaving behind carbon dioxide. The particulate reduction will take place in-cylinder.

The SCR system will most likely affect small to mid-size fishing boats that want more than 804 horsepower. The problem is the weight of the SCR system and the space it requires. Some boatbuilders fear SCR will be heavy, take up room than is available in an already limited engine compartment and add extra expense. That could mean fishing boats will be getting bigger, less efficient and more expensive. And if speed is important, as it is for some Maine lobstermen, they won’t be as fast as they want to be.

Some boatbuilders are looking for alternatives. Joe Hudspeth at All American Marine, a builder of work boats in Bellingham, Wash., offers what he calls Tier 3 Plus. It uses engines in the Tier 3 category — less than 804 horsepower — but boosts their horsepower with an electric motor feeding into a power take-in on the transmission, or uses a ring motor on the propulsion shaft.

There is a bit of flexibility as to when the Tier-4 ruling might apply. Because this is a new regulation, engines between 804 horsepower and 1,500 horsepower don’t have to be Tier 4 certified until Oct. 1, 2017. Engines over 1,500 horsepower, the deadline is Jan. 1.

Either way, be it Jan. 1 or Oct. 1 many boat designs will not be the same.

A collection of stories from guest authors.

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