“You really need an alternative propulsion source you can count to get home for peace of mind,” said one kelp farmer. “If you get stuck, it’s possible there could be no one on the water for miles.”
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A kelp farmer off Long Island in Casco Bay is the first participant in a pilot project by a French electric propulsion maker and Rockland nonprofit Island Institute to test the real-world operational limits of low-voltage electric propulsion in the demanding environments of New England’s working waterfront.
“Safety can’t be compromised when working on the water in Maine in winter,” said kelp farmer and fisherman Nathan Johnson. “You really need an alternative propulsion source you can count on to get home for peace of mind. If you get stuck, it’s possible there could be no one on the water for miles.”
Johnson owns Shearwater Ventures LLC, a kelp farming operation he founded in 2015.
The project centers on the installation and multi-season field-testing of a TEMO·1000 electric outboard motor on Johnson’s 18-foot Rosborough skiff. Tests will measure how well the system performs at water temperatures below 45 degrees Fahrenheit, as well as under heavy harvest loads and during active fishing operations.
French manufacturer
The motor is made by Temo, a French manufacturer of electric outboard motors founded in 2018. U.S. operations launched as Temo USA Inc. in 2024, with a sales office at the New England Ocean Cluster, 68 Commercial St., in Portland and warehouse space at 45 Center St. in Scarborough.
In 2021, the company brought its first product to market, a 450-watt motor for tenders and light boats. The second line, the Temo 1000, weighs 35 pounds and is designed for larger tenders and small sailboats up to 26 feet long.
Electric outboard motors offer benefits that include significantly reduced carbon dioxide emissions, even when charged with non-renewable energy sources, the Island Institute has said. Other benefits include less water pollution, more predictable operating costs and quiet operation.
Grant funding
The project is funded by a $3,000 grant from the institute’s Glenn Fund Community Impact Grants program.
“We support pilots like this because seeing is believing,” Lia Morris, senior community development officer at Island Institute, told Mainebiz. “A boat like Nathan's operating on the water in Maine's diverse seasonal conditions does more to convince the next boat operator than anything else. By providing technical expertise and financial support, we're creating opportunities for more commercial boat operators to see firsthand what's possible and to experience a different type of electric motor."
Data collection
Quantitative and qualitative data across four seasons will include:
- Winter range and cold testing: Validating the motor’s ability to safely return to port from the kelp farm, a one-mile transit, in freezing air temperatures, intense wind and adverse tidal states.
- Spring harvest maneuverability: Assessing thrust and position-holding efficiency when maximum biomass weight is suspended from the kelp lines.
- Summer seining: Testing the viability of electric propulsion to assist with safe operation and net handling during all activities (such as fast-paced pogie fishing).
- Autumn seeding: Evaluating precision handling to maintain strict separation of new kelp lines during long line seeding activities.
Data will be shared through peer-to-peer networking, regional community newsletters and an ongoing multi-year documentary video.
“This project connects directly with local innovators who are addressing both environmental and economic challenges through sustainable aquaculture,” said Nicholas Steenberg, who leads TEMO-US operations in Portland. “Nathan’s story as a seaweed farmer highlights how these efforts support Maine’s coastal communities and ocean health.”
Since the company debuted in Portland in 2024, about 400 TEMO units have sold in the U.S. so far
