Experimentation with "green" vessels drives technology change

The construction of environmentally friendly vessels for the maritime industry is growing.

This trend is influenced by several factors: new emissions and environmental regulations, higher fuel costs, public pressure to make the industry greener and a push from owners to make vessels more cost-effective.

"This is what drives innovations in our industry — the need to be that much cleaner and more efficient," said Matt Paxton, president of the Shipbuilders Council of America.

Efforts to curb emissions range from installing scrubbers to using hydrogen fuel cells or batteries for propulsion. And a host of other green measures are being tried, such as using heavy-metal-free vinyl marine film instead of paint on the exterior, energy-efficient lighting, solar panels or wind turbines to charge electronic equipment and the use of recycled materials in the vessel’s interior.

But the move to building green vessels leads to other questions. What technology makes the most sense? What technology is the most proven and reliable? And most importantly, are these measures affordable? The many interesting green vessels are commissioned by companies large and small, public and private.

Hornblower Hybrid will use a variety of environmentally friendly fuels when it begins tourist voyages around New York Harbor and the Statue of Liberty. Hydrogen fuel cells, solar, wind and batteries will supplement the Tier 2 diesel engines. (Photo courtesy Statue Cruises)

Hydrogen fuel cells

Two vessels currently in the planning stages will use a combination of power sources, including hydrogen fuel cells: a retrofitted research vessel in Victoria, British Columbia, and a new tourist ferry in New York.

Hornblower Cruises and Events, based in San Francisco, is retrofitting a former Florida ferry to transport tourists from Manhattan to the Statue of Liberty.

Hornblower Hybrid, a steel vessel, is 168 feet long and 36 feet wide with a draft of 6 feet 6 inches. When finished, it will carry 600 passengers and will operate at speeds between 6 and 8 knots. The retrofit is being done at Derecktor Shipyards in Bridgeport, Conn. Sea trials are scheduled for April.

Hornblower Hybrid will be powered by hydrogen fuel cells, Tier 2 diesel engines, solar panels, wind turbines and batteries. In addition, the vessel will be able to plug into an electric power source at its berth.

The control system, developed by Hornblower's engineers, will use all power sources, so that the energy from wind turbines and solar panels goes directly into running the ferry.

"We can make the vessel as efficient as possible by pulling from different power sources, depending on the power requirements at that time,” said Cameron Clark, who, as director of environmental affairs for Hornblower Cruises, is overseeing the project.

There will be two Scania 700-hp diesel engines and 192 Odyssey AGM batteries. The hydrogen fuel cells will start out generating 32 kW of power, but the vessel will have the capacity so that the fuel cells can generate up to 200 kW. Other green features include low-VOC paints for the boat's exterior, LED lighting, counter tops made from recycled glass and green-certified carpeting.

The former Canadian Coast Guard cutter Tsekoa II in Haro Strait, moving past Washington's San Juan Island and Mount Baker en route to British Columbia in December 2010. The vessel will undergo a refit that will transform it into a hybrid research vessel using low-emission generators, hydrogen fuel cells and batteries. (Photo courtesy University of Victoria/Val Shore)

Why venture into the relatively new area of hydrogen fuel cells? The company already installed selective catalytic reduction (SCR) units on some of its West Coast ferries, but Clark said they are expensive and result in a net increase in fuel consumption, so they have stopped doing research in that area. (SCR units reduce nitrogen oxide emissions.) Also, fuel cells are twice as efficient as combustion engines.

"If you're going to try to get a more efficient means of providing power, and try to deal with the issue of reducing your carbon footprint, there really isn't any way out there except for fuel cells," Clark said.

In 2009, Hornblower Cruises began running an environmentally friendly 149-passenger ferry in San Francisco that uses a combination of diesel-powered generators, electric motors, vertical axis wind turbines and solar panels. Over two years, fuel consumption in this vessel went down 35 percent, said Clark, but the fuel used is still expensive. And the solar and wind power on this ferry are not used in vessel propulsion. For the company, hydrogen fuel cells are the next step. "Our goal is to show that it is safe and reliable," Clark said.

Clark could not say how much the New York City ferry will cost, but said it cost $4 million to buy the San Francisco vessel and retrofit it. Subtracting research and development expenses, the green vessels Hornblower Cruises build cost 20 to 30 percent more than a conventional vessel.

The decision to retrofit older vessels instead of building new was also made for environmental reasons. With the San Francisco ferry, Clark said the company calculated that it saved 735,000 kW of electricity consumption compared to a newbuild.

Hornblower Cruises builds and operates these environmentally friendly vessels with no government subsidies. Even though the company is committed to building green vessels, there are still commercial considerations. "We are in the business to make money, and stay successful," Clark said.

A hybrid research vessel

A former Canadian Coast Guard vessel, Tsekoa II, is being retrofitted into an environmentally friendly research vessel for the University of Victoria in British Columbia. The electric propulsion system will be powered by low-emission diesel generators, hydrogen fuel cells and batteries. Scientists will use the new vessel to study changing coastal ecosystems, marine resources and continental shelf dynamics.

The retrofit will cost over $10 million in Canadian currency ($10.3 million in U.S. funds), which includes the cost of all scientific equipment, according to the project's lead scientist, Kim Juniper, a professor at the university's department of earth and ocean sciences. Scientific equipment includes a multi-beam sonar system for mapping the sea floor and acoustic equipment to listen for marine mammals. About 40 percent of funding comes from the federal Canada Fund for Innovation, 40 percent from British Columbia Knowledge Development Fund and 20 percent from industry and private sources.

The San Francisco Bay ferry Gemini is one of four low-wake, high-speed catamarans that run on ultra-low-sulfur diesel. The vessels were built by Nichols Brothers for California's Water Emergency Transportation Authority. (Brian Gauvin photo)

BMT Fleet Technology, which has a Victoria office, is working on the design of the retrofitted vessel with help from the university's mechanical engineering department. The power control system is being developed at the university, Juniper said. Tactical Marine Solutions Inc. of Victoria is managing and crewing the vessel. Juniper expects the yard that will do the retrofit will be selected in June and hopes that sea trials will take place by March 2012.

The 88-foot-long vessel will be lengthened by 22 feet to provide room for the fuel cells and batteries, for berths for up to 15 crew and scientists and for the vessel's main lab. There will be two 200 kW azimuth thrusters and 90 kW bow thrusters made by HRP Thruster Systems, according to Juniper. There will be three 175 kW generators.

Because it is a research ship, silent running is important. "When we do acoustically sensitive things we can shut down the generators and run off the batteries," said Juniper.

The hydrogen fuel cells will be the HD6 unit made by Ballard Power Systems Inc. However, the vessel will run just a few hours on the fuel cells. The university will test the performance of the fuel cells in a marine environment and also "test the whole integration of multiple sources of energy," said Juniper. The vessel will use waste hydrogen from an industrial plant in North Vancouver that processes bleaching agents for the pulp and paper industry. Any excess power from the diesel generators will be routed to recharge the batteries, Juniper said. The longest voyage the vessel is likely to make is 311 miles, but most trips will be 31 miles or less from its homeport.

Low-wake ferries

When the Water Emergency Transportation Authority (WETA) was created in 2004 in the San Francisco Bay area, one mandate was to build environmentally friendly vessels. New vessels had to be 10 times cleaner than existing vessels and 85 percent better than Tier 2 emissions standards.

The result? WETA now operates four green ferries: Gemini, Pisces, Scorpio and Taurus.

The high-speed catamarans are each 118 feet long and 29 feet wide. The engines run on a mix of 95 percent ultra-low-sulphur diesel and 5 percent biodeisel, according to Keith Stahnke, manager of operations for the WETA. "Our vessels are in compliance with Tier 3 without having to do anything," said Stahnke.

Each vessel is powered by two MTU 16V2000-M70 16-cylinder marine diesel engines. Emission reductions are achieved using a selective catalyst reduction system, with 12 catalyst monoliths totaling 179 liters in two rows of six. There are two small solar panels that help power the pilothouse lights and electronics. All four aluminum vessels were built by Nichols Brothers Boat Builders of Freeland, Wash., partnering with Kvichak Marine Industries of Seattle.

Pacific Power Generation of Kent, Wash., provided the propulsion system. Incat Crowther of Australia designed the ferries. Two ferries can transport up to 149 passengers each and two carry up to 199 each.

Matt Nichols, director of business development for Nichols Brothers, said it was a learning process building the ferries. “We really did something and made a difference," he said. "It was a great experiment. We all teamed up and made this work"

Although building this type of environmentally friendly vessel can be done, Nichols is concerned about whether the boat is affordable for the private sector, given how marginal the profits are for many companies. "It can be done — at a price. But who pays for it is really the bottom line."

Yankee Freedom III, scheduled for delivery in 2012, will feature Tier 2 diesel engines, solar panels, metal-free bottom paint and vinyl film. Waste heat from the engines will supplement the heating system. (Photo courtesy Incat Crowther)

He is worried about the financial pressure tougher emissions regulations put on businesses. "Everyone is environmentally conscious. They want to do the best that they can," he said. "But you have to be careful. You have to really keep a balance on this. People don't think of the commercial part of it."

Each vessel cost a little over $8 million, according to Stahnke, with the funds coming from local bond issues, part of a $1 increase in bridge tolls, county transportation taxes and the U.S. Department of Transportation ferry boat discretionary program.

The low-wake vessels are more fuel-efficient, but they also replaced larger 300-passenger vessels. The new ferries use about 20 to 30 percent less fuel than the previous boats, according to Stahnke. The ferries operate in a six- to 10-mile area, with a cruising speed of 25 knots for trips of about 30 minutes, he said.

Although these ferries are green, there are some drawbacks. With the emissions control equipment, the engines are heavier. "It is very efficient at speed, but it does not maneuver in a docking situation as well as some of the older vessels,” Stahnke said. “Everything is a tradeoff. Nothing is perfect."

Small tour firm goes green

Jerry and Carol Hill own and run a tourist ferry that takes passengers from Key West to Dry Tortugas National Park, 70 miles offshore. They employ 19 people. When they won a 10-year contract from the National Park Service to provide exclusive ferry service to the park, they decided to replace their 11-year-old vessel with a new, environmentally friendly ferry, Yankee Freedom III.

The new vessel is being built at Gladding-Hearn Shipbuilding/Duclos Corp., in Somerset, Mass., and is to be commissioned in the summer of 2012. The design is by Incat Crowther. Carol Hill said she could not disclose the vessel's cost.

The aluminum catamaran will be 110 feet long and 30 feet 6 inches wide. It will be powered by two Caterpillar 3512C, EPA Tier 2-approved diesel engines turning nibral propellers, according to Duclos Corp. President Peter Duclos. The twin gearboxes will be Twin Disc model MGX6848SC Quick Shift. The ferry will be equipped with two Caterpillar 58 kW generators and a Vosper/MDI active interceptor motion-control system to reduce the vessel's motion in rough seas. Top speed will be over 28 knots.

Hill said the bid for the park service contract was one motivation to build a new, green vessel. She believes the plan for this vessel helped the company land the contract, although it is not receiving any government subsidies to build the ferry.

It is a challenge for a small company to build a boat like this, but Hill said the decision evolved from a process in which the company made its entire operations more environmentally friendly.

"Does it cost more? Yes," she said. "But at this point it is not an option for us. We are never going back." The company's reputation is "that green is now our standard, and the passengers and the crew and my husband and I love it," she said. "In all honesty, I think that everyone should be making whatever effort they can not to pollute the water, the air or our environment."

Other green features on the new ferry include zero-discharge, metal-free bottom paint, vinyl marine film instead of paint on the exterior, energy-efficient lighting and solar panels to charge emergency batteries. Waste heat from the engines supplies the heating system. The ferry will carry its own oil boom.

Still, Duclos said his company is not building a groundbreaking vessel.

"It is a bonus when you can come up with a green feature that saves money. That was our goal — to use off-the-shelf stuff. We're not inventing anything new. We're just packing it in a way that is a modern approach to a green vessel," Duclos said. He is concerned about the extra costs that come with building a green vessel. He mentioned the WETA ferries and said, "I don't think those kind of features are sustainable in a commercial environment."

The future for green vessels

Duclos' concerns get at the heart of the future of green building: the concepts are now technologically possible, but are they affordable? And what technology is the most reliable?

Right now, the trend is clearly at the experimental stage. Hornblower's Clark said everyone will benefit from the wide variety of solutions to these challenges that companies are pursuing.

"Ultimately you are better off if there are multiple people involved" in hybrid technology, Clark said. "It will continue to drive the technology."

Erik Seither, executive director of the Society of Naval Architects and Marine Engineers, said his group is excited about using LNG fuel as a way to drastically reduce emissions. "This low-sulfur stuff will only go so far with heavy fuels," he said. In addition, installing scrubbers on every vessel is a huge challenge in terms of making sure everyone is using the equipment properly.

He has doubts about fuel cells. "At least in my mind, that is a future technology. There is a reliability question. There are a few experimental projects out there, but the manufacturing process is unknown and the cost is unknown," he said.

Clark said the maritime industry is at the start of a major change in propulsion technology, as happened during the switch from sail to steam in the 19th century.

"I do think that diesel engines will disappear. I just can't say when," Clark said. "We have to look at what is more efficient and more scalable."

However, what will ultimately drive green technology forward are major external pressures. "If you see government regulations and/or sustained high fuel prices, you will start to see those looking to adopt technology that will improve fuel efficiency and to find ways to get a better return," Clark said.

By Professional Mariner Staff