Using 100% solar power, a 27’ (8.22m) solar-electric boat has completed a 1400 mile voyage up the Inland passage from Washington State to SE Alaska; the first recorded voyage of this type and an exciting development which brings long-distance electric boat cruising within closer reach.
Father and son team David and Alex Borton left Bellingham, Washington State, on 25th May 2021 in their custom designed and built boat WAYWARD SUN and arrived in Ketchikan, Alaska on 13th June, before continuing to Glacier Bay and Juneau further up the coast. Due to Canadian Covid restrictions, the pair anchored and stayed on board while travelling through British Columbia; no problem with a capable boat and no need to refuel.
An all-solar boat is a dream that has been driving the Bortons for several years and WAYWARD SUN is one of several successful boats produced by their company Sustainable Energy Systems under the brand name Solar Sal since 2014. Designed by Sam Devlin and built by Devlin Designing Boatbuilders of Olympia, Washington, the SOLAR SAL 27 WAYWARD SUN was conceived by David Borton, who also detailed the design for her solar-electric systems.
Unlike most electric boats, which rely on returning to shore power to charge batteries, WAYWARD SUN uses only solar power and has no fossil-fuel combustion engine on board, despite cruising in an area known for cloudy, rainy conditions.
“People always ask us if we have any gas or diesel back-up,” said Alex Borton, “but the sun rises every day. If our batteries get too low, we just wait.”
Propelled by a Torqeedo Cruise 4.0 electric pod drive with six Torqeedo Power 24-3500 lithium batteries, WAYWARD SUN has a separate 12-volt system for lights, electronics and other DC-powered systems and an inverter for occasional AC loads. The batteries are charged from a 1700-Watt array of solar cells on the boat’s rooftop.
“The solar-electric system has more than exceeded our expectations,” Alex said. “During the 45-day passage … we averaged 32 nautical miles a day at an average speed of 3.7 knots. Most of the trip was overcast and it rained a lot. With direct sunlight, we can do 5 knots or more all day without any battery use.”
Until now, the range of most electric boats has been limited by battery capacity. “Thanks to advances in solar cells and Torqeedo’s efficient electric drives and high-capacity batteries, it’s possible to produce a solar boat with reasonable speeds and accommodation that can continuously cruise without ever charging from the shore. If I had more time I would keep going for another 1000 miles.”
Photographs: Alex and David Borton