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Designers Hope Smooth Sailing’s Ahead for Wind-Assist Ferry

Wingsailed Catamaran Among Growing Group of Hybrid Vessel Designs Worldwide

By Karl Vilacoba

The winds of change may soon blow for the commuter ferry industry.

San Francisco-based Wind+Wings Technologies is developing what is believed to be the world’s first wingsailed catamaran ferry, a vessel designed similar to one the BMW Oracle Racing Team raced to victory at the last America’s Cup. Wind+Wings has been shopping the idea to investors and local ferry operators, who have plenty of reasons to follow its progress. In ideal wind conditions, the ship could save as much as three quarters of its diesel costs compared to the oldest vessels in the Bay Area’s existing fleet, according to Jay Gardner, part owner of Wind+Wings.


Gilles Martin-Raget/BMW Oracle Racing

San Francisco’s Wind+Wings Technologies is developing a

wingsailed catamaran ferry designed like this BMW Oracle Racing

Team vessel that won the last America’s Cup.

“That’s a huge number because each one of these vessels is using $1 million or more per year, so you’re talking about potentially $600,000 to $800,000 a year in savings,” he said.

Gardner plans to adapt the wingsail to ferries that can accommodate 400 to 750 passengers and 50 to 100 bicycles. Shaped like vertical airplane wings, the hard, highly aerodynamic wingsails produce more drive and perform better in a wider range of wind conditions than standard sails. According to Gardner, regular cloth sails are not effective in a 90-degree range of wind directions while a wingsail faces limitations in only about a 45-degree range of winds.

The hybrid ferries would be equipped with diesel engines for when the weather is uncooperative, guaranteeing that commuters reach their destinations on schedule. Because San Francisco’s wind patterns are so uniquely favorable, Gardner said the ferries wouldn’t need diesel help at all on many days except for docking. He also believes the ferry would succeed in areas with less advantageous wind conditions.

“Even if 20 percent of your fuel costs were reduced, it can still pay back the investment fairly quickly,” he said.
The winged ferry is an idea 25 years in the making. Racing in the bay with his wife on a catamaran in 1985, Gardner took notice of the diesel-powered ships and wondered why none of them took advantage of the wind. He kept the concept in mind for several years and has recently made headway on it with the help of two firms noted for their work with wingsails. Wind+Wing Technologies has partnered with Huntington Beach, Calif.-based Morrelli & Melvin Design & Engineering for the design of the boat, and with Harbor Wing Technologies, Seattle, for the design and engineering of the wing.

Harbor Wing Technologies is taking the wingsail a nautical mile forward by outfitting it with sophisticated computer capabilities. The ship’s operators need only to program in their desired speed and direction, and the computer will calculate the ideal angles for the top and bottom halves of the wingsails and position them accordingly. This could be a key feature from a sales perspective since buyers would not have to worry about hiring specially trained crews to operate the ships.

“You wouldn’t have to be a sailing expert to run this boat,” said Ken Childress, the company’s director and executive vice president of business development.

Hybrids on the Water

A handful of hybrid ferries are already carrying passengers around the world. Perhaps the Wind+Wings concept’s closest relative is a solar power and wind-assist vessel produced by the Australian company Solar Sailor.

solar sailor

The Australian company Solar Sailor created ferries lined with

solar panels, including on their patented rigid, collapsible sails.

The key to these ships is their patented “Solarsails”—rigid, solar panel-lined sails mounted on the roofs. The ship’s computers can either recommend or automatically change the angle of the Solarsails for optimal sun and wind collection. In poor wind conditions, a system of hydraulics folds the sails down on the roof, solar panels facing up so they continue to collect energy. Australian doctor Robert Dane came up with the Solarsail after reading about how early insects grew wings to draw the sun’s heat before using them for flight.

“The idea comes from nature,” Dane said. “Insects evolved wings as solar collectors and now boats can evolve wings as solar collectors and use them to sail—creating a solar and sailing boat—a solarsailor.”

Versions of the Solar Sailor are on the water in Sydney and Shanghai, with another slated to launch in Hong Kong this year. Three vessels lined with solar panels, but not the Solarsail, are also currently operating in Hong Kong.
According to Dane, the Solarsail boats can save 20-40 percent on diesel in some runs, and about 10 percent over the course of the year. While the company’s focus has largely been on the solar components, Dane said the vessels actually generate more energy from wind when it blows 12 knots (about 13 mph) or more.

San Francisco-based Hornblower Cruises & Events launched the nation’s first hybrid ferry in 2008, a 149-passenger ship powered with assistance from solar panels and 10-foot-high wind turbines. The ship was designed with environmentally friendly materials throughout, from its recycled glass countertops to an exercise bike that generates power for the system. Hornblower will debut the world’s first hybrid ferry using hydrogen fuel in New York City in 2011.

Other Wingsail Applications

The entrepreneurs behind both the winged and solar ferries are marketing their technologies toward a variety of commercial and government uses.

Harbor Wing Technologies is developing a winged, waterborne answer to the drone aircraft for the U.S Navy. The military can use these unmanned vessels for intelligence gathering, patrolling for drug smugglers, search and rescue operations, monitoring environmentally protected areas, water sampling and many other uses, Childress said.

The Autonomous Unmanned Surface Vehicles (AUSV) are designed to remain dormant for long stretches, then spring to action and pursue their target. Childress said they’ll also use their wingsails to scavenge for power—a small generator will allow them to siphon the breeze and produce electricity while the vessels are idle. Commercial uses for modified AUSVs could include undersea surveying and mapping, gas and oil exploration and marine animal monitoring.

Solar Sailor has partnered with a Virginia company to develop a very similar vessel for the Navy called the Unmanned Ocean Vehicle (UOV). Like the passenger ships, their sails would be covered with solar panels and fold down in severe weather.

Childress and Dane believe their technologies could also be applied to freighters, luxury yachts and cruise ships.

Positive Signs

For now, the wingsail ferry’s designers are focused on building a small prototype they can use to gather hard numbers on fuel and emissions savings, and to test how the craft handles in rough weather conditions. Three Bay Area ferry operators, the Golden Gate Bridge Highway and Transportation District, the Water Emergency Transportation Authority (WETA) and Blue & Gold Fleet, wrote letters of interest for the project in 2010.

ferry rendering

Morelli & Melvin Design & Engineering

Wind+Wings plans to build a small prototype to test on the

San Francisco Bay's existing ferry routes this year, followed by

the full-size commuter vessel (shown in artist's rendering above).

Gardner has been working to make believers out of the ferry operators by taking them out on the catamarans he runs for his other business, Adventure Cat Sailing Charters, which gives pleasure tours around the bay. When the prototype is ready, Gardner plans to take the ferry operators along their routes to demonstrate the craft’s feasibility.

Keith Stahnke, manager of operations at WETA, said if all goes well with the prototype, “that would ideally lead to the development of a full-size ferry for daily operations on the bay. We are excited about any innovations and further development of fuel-efficient vessels.”

Gardner sees good omens everywhere. In the wake of BMW Oracle’s triumph at the America’s Cup, Gardner said wingsails are enjoying newfound interest worldwide. Defending champion BMW Oracle Racing is housed at San Francisco’s own Golden Gate Yacht Club. The city recently organized the winning bid to host the next America’s Cup in 2013.

Finally, Gardner believes economics are on his side. When fuel costs shot up a few years ago and constrained the ferry operators’ budgets, it created an opportunity for Wind+Wings’ pitch to be heard.

“When we went to visit them they said, ‘You know what? Two years ago, we wouldn’t have let you through the door, but tell us what you’ve got,’” Gardner said.

In Gardner’s ideal world, the ferries will be on the bay in time to share the winds with the greatest sailors in the world during the America’s Cup.

“I think it would be a phenomenal thing to have a wing-powered ferry boat go criss-crossing the bay at the same time wing-powered Maseratis are tearing up the bay,” he said.

Karl Vilacoba is the managing editor of InTransition.

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