Imagine a future where you and your partner are doing an ocean crossing, and you both get to sleep through the night at the same time. The boat is running on solar power, so there’s no chance of a clog in a fuel line. The boat also has collision-avoidance software that you can set to wake you if another vessel gets close, or that can simply adjust the boat’s course on its own, in tandem with your radar and AIS, while you remain happily in dreamland.
At least some of that future vision will be reality in a matter of years—not decades, but years—according to Pieter-Jan Note, the co-founder of Project Mahi.
In April, the 13-foot uncrewed surface vessel Mahi Two, which Note and his team designed, became what’s believed to be the first of its kind to cross the Atlantic Ocean using only solar power. Mahi Two’s 4,300-nautical-mile journey took six months, from Spain to Martinique, and the last 700 nautical miles were completed after vessel-to-shore communications were lost. Mahi Two simply navigated the last stretch to Martinique all by itself.
This kind of success is a major step forward in developing technology for commercial and, then, recreational boating applications, Note says. “People need to see that it works, that you can depend on it,” he told Soundings. “We were very excited that our vessel made it across. That is a good precursor to show that the technology is evolving, and in a few years’ time, we will have these systems on recreational boats as well.”
Mahi Two is built with a composite hull and driven by a Torqeedo Cruise 2.0 pod drive, which the team modified to rotate so it would be less susceptible to damage from big ocean action. “I did not want something as vulnerable as a small rudder,” he says. “I wanted something that was sturdy and all contained within the vessel. Our actuation is fully internal. It’s like the steering systems you have on board power vessels. They do have rudders, but we only want as few moving parts as possible. Instead of having a rudder and shaft with a propeller on it, we only wanted to rotate the entire motor, the pod drive from Torqeedo, to eliminate one moving part.”
The Cruise pod drive aboard Mahi Two is powered by two 24-volt Torqeedo lithium-ion batteries, which are charged by Solbian solar panels. The system powers the drive, plus the steering actuator, electronics and bilge pumps. Onboard steering, communication, hardware integration, navigation and energy management are all managed by software that Project Mahi created. The boat communicates using an onboard satellite modem, GPS and AIS.
“The vessel had predefined waypoints on the trajectory, so in case we lost contact, it would just continue,” Note says. “Intelligence on board didn’t need to be connected to us. It let the vessel detect other vessels and take evasive actions to avoid collisions.”
When the team laid eyes on Mahi Two in the Caribbean, it was in “quite good shape,” he adds. “All of the electronics were OK, so we could copy all the data.”
Torqeedo—a leader in electric and hybrid drives for recreational boats—took part in the project to help demonstrate the durability and reliability of solar-electric technology for autonomous, long-range missions. Torqeedo-powered electric drives are currently being used on hundreds of uncrewed surface vessels around the world, mostly operated by government and commercial entities for seafloor mapping, oceanographic survey, harvesting data from underwater sensors and surveillance operations.
“Really, the story for Torqeedo is durability, and the potential for solar power to power vessels,” says Tess Smallridge, who handles marketing for Torqeedo. “Electric motors are quiet. They sometimes feel like they’re fragile and a little weird. This one just went 4,000 miles across the ocean for six months with no maintenance, no nothing, on its own.”
Note, who is a lifelong sailor, sees the technology around autonomous and sustainable boating evolving in ways that will only continue to benefit families like his, which sails aboard a Beneteau Oceanis 46. “The idea is to develop situational awareness and collision-avoidance solutions that could also be beneficial to recreational boaters,” he says. “My dad is now looking to buy an electric motor for his dinghy. I think a lot of people are thinking about this. We need viable alternatives, and those alternatives are becoming a lot more mature and useful.”
This article was originally published in the June 2022 issue.