STONINGTON, Maine — There are two major, recurring expenditures for the lobstermen who work Maine’s coast: fuel and bait.
Bait is the more expensive of the two, but that’s a bit misleading, as fuel is a factor in bait costs. It’s caught on boats that use diesel, and often shipped by the same before it gets to the lobstermen who will use it.
So it’s the price of fuel that’s on the forefront of most fishermen’s minds when they consider ways they could save money — an ever-present question, especially with lobster prices staying low this year despite supply returning to normal after last summer’s record glut.
“If fuel prices get much higher, we’re gonna have to go to sailboats,” said Mark Brewer, a lobsterman in Boothbay. “If there was an electric boat I could plug in at night, then go lobstering all day, I’d go for that.”
Electric it’s not, but a team from Penobscot East Resource Center and Maine Maritime Academy have successfully tested a new boat design they say will increase fuel efficiency by 20 to 25 percent.
The boat utilizes a three-hull, or “trimaran,” design to cut down on drag. There’s a lot of physics and naval engineering at play here, but Doug Read — a naval architect and professor at Maine Maritime Academy, who was contracted by PERC to design and test the boat — said it can be understood pretty simply by imagining a boat’s wake.
“If you picture the wake a boat leaves, the waves trailing behind it, up to half of your engine is dedicated to the energy to make those waves,” he said. “The way the trimaran saves fuel is by drastically reducing the proportion of energy your spending on making those waves.”
Read was first contacted by PERC in 2010. He held several meetings with groups of lobstermen, talking about what challenges they faced and what they’d like to see in a new lobster boat design.
“They want wider and wider boats, but when you do that, you tend to drive up the power requirement,” he said. “But if we go to a multi-hull design, you can sort of separate the wide beam we want from the power requirement.”
In May, after three years of design and construction work with his students, Read put a one-fifth scale model of his hull design through the motions at a testing facility in San Diego, Calif. The results went exactly as predicted.
“We proved the power reduction we were expecting, side by side against a modern Maine lobster boat,” he said. Not only was fuel efficiency up between 20 and 25 percent, but the boat was stable in the water despite the unorthodox hull design.
“From what we saw, it handled the water quite well,” Read said. “The motions were comparable to the traditional boat.”
While the boat maxes out at around 25 percent increased fuel efficiency, that’s not applicable at all speeds. The trimaran reaches peak efficiency between 12 and 18 knots. Around 25 knots, traditional boats — which begin to hydroplane at the speed — become more efficient. Brewer said the 12-18 knots speed is fine for average lobstering use.
He has seen fuel prices double in the 25 years he’s been fishing. While the fuel consumption of each lobsterman varies widely — it depends on the size of the boat, the motor, how far out the traps are set — Brewer said the average this time of year is about 30 to 50 gallons per day.
At $3.80 per gallon, that’s $2,280 to $3,800 per month, assuming the boat’s out five days per week. If a fisherman could cut fuel usage by up to 25 percent, that could mean saving thousands of dollars per year.
But efficiency and stability aren’t the only things that matter to Maine’s lobster harvesters, said Robin Alden, executive director of PERC. She said that while the fishermen consulted by PERC and Read were supportive of the project, they had one condition: “It’s got to be pretty.”
“The traditional lobster boat means a lot to people,” she said. “That aesthetic, it’s iconic. Nobody wants to be on some square boat. Doug has figured out how to put a trimaran hull on, where topside will look very similar to the traditional boat.”
Now that a small model has been tested, PERC wants to see either a half-scale or full-size prototype.
Follow Mario Moretto on Twitter at @riocarmine.