2021 was an interesting year for electric outboards. In the spring Mercury announced that they will launch a new line in 2023. Then Yamaha debuted their HARMO electric outdrives at the IBEX (International BoatBuilders’ Exhibition) in September. A couple of relatively unknown companies also showed prototypes of high-power electric outboards. Now that General Motors has decided to pursue electric boat building (“GM Acquires 25 Percent Stake in Pure Watercraft to Accelerate All-Electric Boating,” 11-22-2021), it’s time to get serious about electric outboards…
(Pure Watercraft photo)
Advances in high-efficiency motors and lithium-ion battery technology are slowly finding their way into electric-powered boats. Since we normally think in terms of “horsepower,” maybe it’s also time to recalibrate how we think about an electric outboard’s power. How do you measure horsepower, anyway? (OK. One horsepower is equal to 550 pounds of force to move at a speed of 1 foot per second; or if you’re on a boat, 65 lbs of drag at 5 knots…). Electrical power is easy to accurately measure -- voltage times current, or watts. Torqeedo rates their 3-kW motors as equivalent to 6-hp gas outboards; and their 10-kW motors to 20-hp outboards. So if you really can’t make the switch, take the peak power of an electric outboard in kilowatts, and then double it to get a (very) rough idea of the equivalent horsepower. In the end, however, whether it's a gas or electric outboard, the thrust exerted by the propeller -- in pounds of force -- is what actually gets (and keeps) the boat moving. That’s the number we’re really looking for; and it’s obvious that it depends on more than “power.”
Besides Mercury’s and Yamaha’s plans to produce electric outboards, as noted above, we can reasonably anticipate that other established manufacturers like Honda and Tohatsu will soon include electric outboards in their lineups, and possibly transition to fully-electric at some point. A couple of long-shots worth watching announced their plans at the 2021 IBEX show. Rhode Island-based Flux Marine (www.fluxmarine.com) will introduce 15, 40, and 70 hp electric outboards in 2022. And Vision Marine (www.visionmarinetechnologies.com), a Canadian company that is now listed on the NASDAQ, claims they will begin delivering “the world’s most powerful outboard” – their 180-hp eMotion – to OEMs. [Coincidentally, Evinrude, which was owned by Quebec-based BRP (Bombardier Recreational Products), branded their high-efficiency, high-output gas outboards “E-TEC.” And BRP exited the outboard business in 2020.]
But Pure Watercraft (www.purewatercraft.com), a Seattle-based tech start-up, might be the closest to actual production. Back in 2010, after the Great Recession, Pure Watercraft got venture capital to develop and manufacture a 25-kW electric outboard and integrated battery pack. They used the playbook from Tesla Motors, starting with a clean sheet design, developing their own PMAC (permanent magnet alternating current) motor and gearbox, and building a bunch of not-for-sale prototypes from components and systems they produced in-house. The Wye Island (MD) Electric Boat Challenge is a 24-mile circuit that has been run every year since 2001; and in 2017 Pure Watercraft finished the course in just over an hour, setting the course record – still unbroken – with one of their prototypes (see “Wye Island Challenge – An Epic Marathon” in their website blog). At the end of 2021 GM invested $150M in the company, apparently as part of its plan to diversify beyond automotive applications.
Each of these start-ups listed above began taking reservations at the end of 2021 for their as-yet-unreleased outboards. The $64 question now is, Who will deliver the goods? But I think the biggest unknowns are how exactly GM will leverage their investment in Pure Watercraft; and if other automotive manufacturers will pursue similar deals of their own. We can anticipate that lower-cost, higher-performance lithium-ion battery technology will continue to benefit from the economies of scale that automotive manufacturers and suppliers bring to the table.
www.soundingsonline.com/news/mercury-announces-plans-for-electric-outboards
