This story was originally published by The Maine Monitor, a nonprofit and nonpartisan news organization. Visit the newsroom online: themainemonitor.org.
From a distance, what appears to be an old pontoon boat with a shade canopy was tugging at its mooring near an island in Casco Bay. Up close, the retrofitted pontoon is actually something quite new: An oyster-processing barge that operates without a gasoline-fueled generator.
The shade canopy is really a 2.4-kilowatt solar panel array. What looks like a big cooler is a box of marine-grade lithium batteries tied to an inverter. They turn solar electricity into alternating current to run a tumbler, water pump, and other equipment. At the stern is a 20-horsepower equivalent Torqeedo electric outboard for piloting the barge around the floating oyster cages.
The barge was built by New Gloucester-based Shred Electric. Shred has also fabricated a custom, 26-foot aluminum work boat powered by a large electric outboard. It can transport oysters and keep them cool in a solar- and battery-charged refrigeration unit called a ShredCube, which fits in the bed of an electric pickup truck.
Taken together, these are the major pieces needed to operate a carbon-neutral shellfish farm from cage to plate, delivering the product to restaurants or seafood dealers without using fossil fuels.
Shellfish farming is a small but fast-growing segment of Maine’s seafood sector. Now these enterprises — and more broadly the aquaculture industry — are emerging as first movers in the quest to electrify Maine’s working waterfront.
Phasing out gasoline and diesel fuel has obvious climate and pollution benefits, but there’s also a business case for electrification. Enduring the constant drone of gas-fired generators and breathing the fumes are hazards for sea farm workers. Generators are also finicky to maintain around salt water, and the noise can annoy shoreside residents. Solar and battery power could lower operating costs and create quieter coves.
Up and down the Maine coast, a transition is underway in how energy is used in aquaculture. But as with many tech transitions, this one has relied on a mix of public and private subsidies to lower capital costs.
Key contributions have come from the federal government. Now, with funding for clean energy being pulled back under the Trump administration and Congress debating what programs to eliminate in the controversial budget bill, it’s unclear if the pace of change may slow.
Shellfish farming in Maine — chiefly oysters, mussels, and scallops — generates $85 million to $110 million in annual sales, according to the Maine Aquaculture Association. That’s only a seventh as much as the state’s iconic lobster industry. But with 200 farms and more than 700 year-round employees, shellfish is becoming a fixture of the working waterfront.
Anyone who spends time on the water, especially in Casco Bay and the Midcoast, can spot the grids of floating cages tucked into coves and estuaries, as well as work boats shuttling back and forth.
Shellfish farmers consider themselves stewards of the environment, even though their operations depend on gasoline and diesel. But the predictable hours of operations and proximity to shore also make shellfish farms good candidates for electrification.
To envision what’s possible, Nick Planson, Shred Electric’s founder, and Chad Strater, who heads The Boat Yard LLC in Yarmouth, a marine solutions company, offered a tour in May to show off the pieces of a petroleum-free operation.
“We’re right on the cusp of doing it all,” Strater said. “The technology is there. We want this to be something that everyday [farmers] see the sense of.”
Planson and Strater operate out of the Sea Meadow Marine waterfront business hub on the Cousins River in Yarmouth. Hanging on a pier is a Level 2 EV charger. Planson plugged in his 2022 Ford Lightning.
“If we’re electrifying everything,” he said, “I can’t be pulling up in a diesel truck.”
In the pickup truck bed is the cooling unit, the ShredCube. It’s more than 5 feet long and 3 feet tall and wide. It can eliminate the need for ice or idling refrigeration trucks. The $8,000, patent-pending cooler is cloud-connected, so temperature, location, and other data can be monitored on a smartphone.
The boat was built with a $181,500 federal grant for designing an electric work boat for the aquaculture industry. It’s powered by a 100-horsepower equivalent Flux Marine electric outboard, manufactured in Rhode Island. Roughly 800 pounds of batteries buried under the deck recharge overnight at the dock.
When Strater pushed the throttle, the vessel rose quickly onto plane. It performed just like a gasoline outboard, only quieter. In a few minutes, the boat was at the mouth of the Royal River, heading to a point off Littlejohn Island in Yarmouth.
A few miles up the bay, near the entrance to Harraseeket Harbor in Freeport, roughly 2 million oysters are under cultivation at Maine Ocean Farms. Charging is one of the biggest hurdles facing marine electrification, according to Willy Leathers, director of farm operations.
But the farm is about to address that problem, as part of a $1 million project funded in part with a $500,000 US Department of Energy grant, along with other partners. It will pay for two chargers to be installed in Portland and Yarmouth. The project includes a custom-built aluminum workboat from Fogg Boatworks in North Yarmouth and twin 120-horsepower electric outboards.
A separate, smaller barge project funded by the USDA, The Nature Conservancy, and the Island Institute is nearing completion. It will be powered by six solar panels and a small wind turbine. It will include an upweller, a tank system that pumps seawater to raise oyster seed, or spat.
Maine Ocean Farms will send 350,000 oysters to market this year. With the new electric boat and access to chargers, the company can deliver oysters by water to businesses on the wharfs in Portland. That can eliminate the step of offloading in Freeport and trucking south.
“We make constant efforts to innovate and find efficiencies in what we’re doing,” Leathers said. “If I can reduce workplace noise and emissions, that will have the biggest impact on my employees.”