Propulsion Choices for Lower Emissions

By Kathy A. Smith

EPA emissions regulations are keeping a lot of engine manufacturers busy as they enhance various existing product lines for fishing applications, while also developing new technologies for after treatment options, in advance of the looming Tier 4 requirements. Meanwhile power generation companies are also working hard to keep pace with today’s commercial fishing customer needs.

“Tier 4 is a phased-in emissions regulation and it depends on the engine horsepower,” says Geoff Conrad, Director, Marine Business, Cummins Northwest. “The EPA is trying to “emissionize” the bigger engines first because they are the biggest contributors to the emissions issues. It starts with what they call the EPA Tier 4 in 2016, with the balance of engines being done in 2017. This is only for engines above 805 HP or 600 kW.”

Engines below that are required to be Tier 3. “When you get into larger medium speed engines, then there is a split on technologies to achieve emissions reductions,” Conrad says. “The EPA does not dictate the technology used to achieve this. All they care about is overall emissions reduction, and this is up to the manufacturer.”

Cummins has a full line of marine certified Tier 3 products but because of the changes coming down through the various Tiers, conversations with customers are changing. “Most of our conversations with a customer today center around what emissions level are you designing for or needing in your area where you’re going to operate. That dictates what options we may have for that customer.”

Moving from Tier 3 to Tier 4 is going to be a significant event in Conrad’s estimation. All industrial and trucking markets have also had to come to terms with similar changes. “It’s almost like you need to be a specialist in chemistry and legal matters,” he says. “With Cummins Northwest, we have specialists in our employ whose sole job is to guide customers and our organization on what’s allowable under the rules.”

In Tier 1, there was a fairly significant reduction of NOx. Conrad says It was achieved by changing the timing of engine, which had minimal impact on the customer back in 2000. In 2007, Tier 2 helped further reduce NOx, with introducing the treatment of particulate matter. During this phase, engines were also beginning to optimize the fuel system and combustion process, which again, was manageable for the end user. “Now you get into Tier 3 and we’re now further reducing particulate matter and have almost cut it in half,” says Conrad. “That’s where we are today.”

Cummins places a lot of emphasis on being the emissions leader. “A lot of governments, industry organizations and environmental groups rely on us to give them good and sound technical advice,” adds Conrad. “In many cases, we help shape the rules in different regions of the world who are coming to terms with emissions issues. No matter what Tier you’re working with, ownership of compliance on an engine is a shared responsibility between the engine manufacturer and the owner/operator of that engine. These EPA emissions levels are the most stringent in the world. But there is a consequence for it. The technology incorporated into the engines, e.g. Selective Catalytic Reduction (SCR), all require high cost and a high level of technical design. You just can’t take an older engine and put this on it and expect it to work.”

For Tier 3, which for Scania, began in January of this year, the company offers an inline 6, 13-liter engine that starts at 250 HP and goes up to 675 HP as well as a V-8, 16-liter engine that starts at 550 HP for Tier 3 and goes up to 900 HP for different commercial fishing applications.

“It wasn’t much of a challenge to meet Tier 3,” says Sheldon Murdock, Sales Manager, Marine Department, Scania USA Inc. “Everything we did was based on existing in-cylinder technology. We just increased the efficiency of the engines, which is part of our normal process. We did drop in power to meet Tier 3 on the higher end in that we had a 1000-HP engine in Tier 2, which went to 900 HP for Tier 3.”

Scania AB, the parent company, manufactures on-road Class 8 trucks and buses for various segments and the European emission standards are pretty stringent. So the technology Scania uses for on-highway products usually ends up translating down to their industrial and marine products.

For Tier 4, Scania sees that new standards will mean a SCR after-treatment. They are already developing a new engine product to meet that emission standard which they expect will be available for the US market close to a year before it’s necessary in the US.

“It definitely costs our company a lot of money to develop the technology for this,” explains Murdock. “I wouldn’t say that it has affected our price to the customer drastically. The SCR step definitely will add some extra costs and some extra components to the system, which in the fishing industry becomes a challenge because you have space constraints, depending on the type of boat you’re operating. I think the major challenge for Tier 4 is going to be how we incorporate the SCR system into the different fishing vessels. It will be on a case-by-case basis and I think a lot more application engineering will be necessary for some of these vessels.”

Since Scania already provides engines for the on-highway truck business in the neighborhood of 70,000 trucks per year, the volume of that business is already paying for the majority of engine after treatment development costs.

Fred Lachlan, Marine Sales Manager, Volvo Penta, Region Americas based in Vancouver, BC, says in Canada with regards to marine engine emissions, the country is following old IMO legislation from about 15 years ago but they’re likely follow in the footsteps of the EPA. When this will happen remains to be seen.

Like Scania, Volvo also makes diesel engines for truck, industrial and construction equipment, so in theory they could move ahead to Tier 4. However, as Lachlan points out, “Not only is it going to be an installation problem because you won’t be able to fit the whole SCR package in there but the cost will go up at least 20 to 40 percent.”

The current big seller for Volvo Penta are engines in the 200-600 HP, 3 to 13 liter range but they don’t have an engine today that’s complaint. “We do have a new 8L engine coming out down the road but it won’t be out until 2016, so we’ve lost some market share because of that, but our top key focus is to go back and grow our commercial business throughout the US in the fishing market. Today what we have to sell in the US in the commercial business is a D4 and D6 (fully electronic diesel engines). For larger fishing boats, we have a D11, D13 and D16 liter.” To that end, Volvo Penta has a contract with a West Coast Builder for some Alaskan boats with a number of 11 liter engines.

In Canada, for marine engine certification all that’s needed is a stamp of approval from Transport Canada. In the US you have to have the Tier 3 label affixed. “Yet people are selling non-compliant engines into the market and that hurts us. If the Canadian dollar was weaker to US, there would be more people coming up to buy boats and they’d have to buy a compliant engine. Some owner/operators want a Tier 3 engine regardless, whether they’re in Canada or not. It all comes down to the cost.”

“Clearly the impacts of emissions regulations, the more advanced technologies being employed and the research and development costs are driving up the cost of everyone’s product,” says Bill Mossey, Vice President of Pacific Marine Power, a division of Pacific Power Group. “The rate of change of the emissions standards as we migrate through Tier 1, Tier 2, Tier 3 and Tier 4 has caused almost all manufacturers to invest large amounts into emissions development and compliance.”

The changes to the engines are significant enough, e.g. for Tier 2 to Tier 3, that in some cases manufacturers are employing technologies that allow fuel efficiency improvement while in others a deterioration of fuel consumption rates occur.

“For Tier 4, with engines that use on-engine solutions, which is normally cooled exhaust gas recirculation (EGR), the engine can’t be as fully optimized for fuel consumption as with SCR after treatment-based solutions,” explains Mossey. “In addition, cooled EGR requires low sulfur fuels, while SCR has a greater tolerance in the fuel sulfur content. Both technologies, cooled EGR and SCR, add devices and complexity over Tier 3 for maintenance, repair and capital cost.”

The compromise with SCR after treatment is having to carry another fluid on the vessel as part of that system. There is an off-engine component, which is the exhaust after treatment device, which is fairly large, takes up space and has to be installed and have certain levels of maintenance. The benefit of SCR exhaust after treatment is that it allows for further optimization of the engine for fuel consumption, normally more than offsetting the costs of the reactant fluid, urea. Depending on the load factor, according to the Mossey, urea consumption will be around three to five percent of fuel consumption.

In the Tier 3 realm, Pacific Power offers MTU engines from 750 to 2,680 HP as well as Tier 3 generator sets from 65 kW to 1,800 kW. Looking ahead to Tier 4, Mossey advises commercial fishing vessel owners to build now to save money and complexity.

“It’s a pretty simple story for us right now as far as propulsion goes in the US EPA T3,” says Colin Puckett, Vice President of Sales and Marketing, Northern Lights, Inc. “We are no longer dedicating product development resources to new models. As a boutique propulsion engine manufacturer with highly specialized applications and fairly low volumes, it doesn’t make fiscal sense for us to produce certified EPA engines for the propulsion business. That’s why we’re focusing on our core markets of power generation and marine climate control.”

Northern Lights have been expanding their power generation range and have marine packages from 20 kW up to 500 kW. They’re also working on developing a series of auxiliary engines for commercial markets for deck-mounted machinery, pump drives and barge units.

The company still offers their popular Lugger engines for non-EPA projects and they are committed to continue supporting existing customers with parts and service. This summer, they’ll be commissioning a newly-built hybrid system in a catamaran application that could prove a good alternative for commercial fishing down the line.

“We understand the hesitancy in the industry about this new technology,” says Puckett. “The equipment and installation are neither traditional nor inexpensive. You can’t get a hybrid system for the same price as diesel; in many cases, it can be twice the price. You have to have a good reason, plan and understanding of your return on investment profile before you make the leap.”

For example, Puckett says for some fishing applications that spend a lot of time loitering and not under power with their main engines, hybrid can make a lot of sense because operating large diesel engines at idle speed for long periods of time is a very inefficient use of the engines. “If you can run that time with a more efficient system or even with battery power to run deck and hydraulic equipment, you can see a real quantifiable return on investment in a reasonably short amount of time.”

Although hybrid is not a one-size-fits-all solution, it is something to consider. “We want to stay ahead of the curve on this because our customers are asking for it,” adds Puckett. “As EPA gets tougher, everyone has to comply. Nobody wants to be the guy with black smoke coming out of his stack. We want to help be a part of cleaner technology in the eyes of our customers through a strict compliance program and our contribution to the embodiment of what a clean, modern vessel should look like when they fire up their engines.”

Carl Micu, Manager, Engines and Drivetrain Sales, North and South America for John Deere says, “We are not doing anything with after treatment in the marine world as of today because of our power category. Everything we do is below 805 HP.”

John Deere offers a wide range of Tier 3-compliant engines, from 4.5 liters to 13.5 liters. The 4.5- , 6.8- and 9-liter engines use high-pressure common rail fuel systems while the 13.5-liter engine uses an electronic unit injection system. All have four valve heads to help with emissions.

The company’s 4.5 liter is very popular for the 99-kW power node. “The sales are very strong with this engine today,” says Micu. “With Tier 3, we were able to develop the 4.5 liter to produce enough power to meet the emissions requirements, but we’ve made that package more compact for customers while still offering the same type of performance. We have some engines in Alaska powering various types of vessels for the fishing market. And we also offer auxiliary on-deck engines for winches that are radiator-cooled applications that meet Tier 3 marine requirements. The other benefit is all of our engines are capable of being keel cooled, and that’s important in the Northwest for commercial fishermen as they don’t want to sea cool anything.”

John Deere has taken a building-block approach to engine development and try to keep installation requirements as common as possible for the customer throughout the Tier changes.

“We love the fishing market,” adds Micu. “They’re good to us and we hope we’re good to them. We know some of the seasons are really short, and we understand the importance of ensuring fishing vessels are up and running when they need to be.”

John Deere has been providing EPA-compliant engines for commercial boats since 2004 when the EPA regulations began. And as Greg Light, VP Sales and Marketing for Cascade Engine Center, a Seattle based marine and industrial engine distributor says, this is the 10-year anniversary of those EPA regulations.

John Deere has been a great repower product for commercial fishing vessels, providing fishermen a great option that have kept their engines running from the 70s and 80s. One advantage that has given Deere an edge in this market is their single circuit keel cooled engine design. An additional keel cooler can cost up to $8,000 according to Light.

“If you can stay with the single circuit system and maintain the same kind of performance and horsepower, it only makes sense to stay with that single circuit,” he says. Dual circuits are generally appropriate for higher horsepower applications, something toward which Deere is moving for future models. Deere also provides auxiliary drives and PTO options. Crankshaft PTO power ratings have recently been increased on many models. Marine engines are available in both 12- and 24-volt models as well as heat exchanged versions.

John Deere engines have repowered crabbers, seiners, gillnetters and trollers that fish throughout the Pacific Northwest and Alaska. Currently, Little Hoquiam Boatworks is building several fish boats that are John Deere-powered.

Additionally, Light reports that there have been a significant number of Bristol Bay boats built with Scania power in recent years because of its power-to-weight ratio. Two new seiners have been built at La Conner Maritime Fabrication in La Conner, Washington. “One has just been launched,” he says. “They’re built to the new Coast Guard guidelines so they are just under 50 feet long and do not have to be classed. Each of them has 16-liter, 900-HP dual circuit Scania engines.” Seven vessels were repowered in British Columbia this last year ranging from heavy displacement commercial fishing vessels to high-speed surface drive applications.

According to Light, Yanmar Tier 3 engines have been very popular in the Cordova/Copper River Fishery due to their light weight and high speed which lend themselves well to jet application, both in single and twin. And Cascade has recently added the FPT marine engine line, which adds to their high-performance commercial engine line up.

Regarding future Tier 4 applications in 2017, Light says it’s unclear where some manufacturers are headed but there are industry discussions on possible workarounds to meet emissions regulations. “What we’re hearing is, for example, if a boat was going to be designed and it needed 2,000 HP, instead of two 1,000 HP engines installed, you might put in three 700-HP engines to stay under the Tier 4 600kW/804hp threshold.”