Dena Hankins is on a global voyage aboard her 1984 9m Baba 30 converted to run with an electric propulsion motor – possibly the smallest electric sailboat to circumnavigate the planet

When we reached Horta on the second leg of our electric sailboat circumnavigation, my partner James stayed on Cetacea and I rowed in alone.

As the gap widened between me and the 1984 Baba 30 that we’d just spent 29 days sailing from Bermuda to the Azores, I knew we’d made the right decision converting to an electric motor.

We’d pulled into Horta with 31% of our propulsion battery power remaining (71 generous amp-hours) after using the electric motor without compunction and to good effect, keeping our tacks to a minimum and our angle tight to our destination.

After clearing in and enjoying a fortnight on Faial, we finally sailed to the place we’d hoped to reach for well over two decades: Velas on São Jorge in the Azores.

My maternal great-grandparents, Rosa and Antonio Azevedo, were from São Jorge. My grandpa was born in New York and nicknamed Spud when his three-year-old hands were put to work peeling potatoes so the family could get ahead.

The US became home for the Azevedo family, but I felt drawn to cross the same ocean and stand where they said goodbye to those who stayed. The electric motor conversion is what got me there.

Dena rows her tender, Tursiops, back to Cetacea after clearing in to the Azores in Horta

Dena rows her tender, Tursiops, back to Cetacea after clearing in to the Azores in Horta. All photos credited to: James Lane/Dena Hankins

Non-diesel decider

In 2022, we left the North Shore, above Boston, Massachusetts, USA, with every intention of shaking down the boat’s original systems and diesel engine over a few weeks, and then leaving Narragansett Bay for the Azores.

As we sailed from Gloucester to Provincetown, I tried to address a new oil leak by tightening the bolts for the timing gear cover. One bolt broke off inside the engine. Excavating and replacing that broken bolt was the beginning of a 10-month struggle that ended with jettisoning the old diesel and installing an electric motor.

Despite having dedicated ourselves to a car-free cycling life a decade earlier due to the role of fossil fuels in climate change, we struggled with the expense and difficulty of going electric on the boat. We felt the battery technology just was not there yet.

Weeks went by as we limped along, replacing gaskets and fasteners and unendurable amounts of oil.

Finally, we had to admit that we could no longer trust our 38-year-old diesel engine.

We put aside our ocean-crossing plans and coastal-hopped for the remainder of the summer: Maine, the Bay of Fundy, and Yarmouth, Nova Scotia. On that Downeast run, we changed the way we travelled.

With electric propulsion in the backs of our minds, we sailed onto and off the anchor whenever possible, and turned south for winter.

We watched other sailors on AIS gaining speed when the wind eased, while we sought the wind further offshore and it rarely failed us.

By the time we got halfway down the Eastern Seaboard, we were solidly on a new path.

The conversion

Cetaceaʼs tower with two 500W wind turbines and 800W of solar power

Cetaceaʼs tower with two 500W wind turbines and 800W of solar power

As non-engineers who do all our own work on Cetacea, we needed an electric propulsion system that was accessible and comprehendible to a layperson.

That had us leaning towards a complete motor rather than one of the kits. We have always planned our sailing trips to make use of favourable currents and avoid bashing into wind and waves, so our motoring needs were largely getting into and out of harbours.

Even on our trips along large rivers, we sailed and used the natural forces to help us along.

Everyone needs enough power to overcome a foul current now and then but we are very happy to drop the hook and wait for the turnaround.

Thinking that way, we chose a 10kW, 48V motor to replace the 20hp diesel. The battery system took more thought.

We have always been satisfied with absorbed glass mat (AGM) battery tech and it seemed the safe choice. Most electric motor installations are done with lithium phosphate, however, and the more we researched, the more we realised why. Lithium iron phosphate batteries (LiFePO4) can be partially charged over and over without damage, can be drawn down to extraordinary percentages of their capacity, are lightweight, compact, and the price is now comparable to those heavier, bulkier, quality AGM batteries.

So we decided to build a single 230Ah, 51.2V battery pack of 16 individual 3.2V lithium phosphate cells, with its own battery management system (BMS) to control the charge, discharge, and balancing of the cells.

We already had an aluminium tower aft to support four 100W 12V solar panels and a 12V Rutland 1200 wind turbine on its own pole. Rutland also makes a 48V model and we became a twin wind turbine boat with a ‘goal posts’ support system.

We moved the top two 12V house solar panels to the sides of the cockpit and installed two 200W, 24V solar panels in series on top of the tower. This is possibly the smallest 1,800W wind and solar farm in the world.

We did the conversion on a mooring in Marathon, Florida, using a rowing boat to transport the solar panels out and heave the new motor aboard. After massive labours the old diesel was out, the bilge cleaned and repainted, and the electric motor installed.

The battery pack came together with surprising speed in the same cabinet that held the old diesel and, just like that, we were an electric sailboat. We realised that, with our travel plans, we could set a record as the smallest electric sailboat to circumnavigate the planet.

A bolt snapped off leaving part of it buried the engine block

A bolt snapped off leaving part of it buried the engine block

The shakedown

Our first propulsion test was a gentle forward and reverse against the mooring pennants. The second was a 1.5km trip out of Boot Key to the anchorage in open water.

The next day, anchor up on glass, we motored gently away from the Key. At slack current, I slid the throttle to full and watched as we made and held 5.6 knots (faster than usual) with an amperage draw and revolutions per minute well within the manufacturer’s specs.

We should have been good to go. But the 48V Rutland wind charger had yet to come out of standby, and we had to get it working properly before we went offshore.

The manufacturer, Marlec, agreed to send a replacement controller to their distributor in Florida, so we headed toward Fort Lauderdale.

As we approached Key Biscayne, our VHF radio went into alert mode. Storm cells were heading our way and officials recommended returning to port. As one of the slowest boats on the water, the powerboat procession tossed us on their wakes worse than the storm-driven waves.

Several less dangerous cells passed over and then, with both of us in the cockpit, the most shocking thing happened: Lightning snapped between our bodies. It did not come from above or branch out downward, it simply popped between our chests.

The electric motor was engaged and supplementing the tiny amount of staysail we had left unrolled, but it never faltered. The only shock greater than seeing the spark instantiate and dissolve was realising that we had not lost any of our electronics or propulsion equipment.

A major criticism levied by Floridians of the electric motor conversion is the vulnerability to lightning strikes. Our electrically unbonded boat survived that threat without damage. Instead, we fixed our wind-charger problem and took off on our circumnavigation.

Dena glories in swimming mid-ocean

Dena glories in swimming mid-ocean

Bermuda-bound

Completely unexpectedly, we used our new propulsion system most days. When the sailing was good, it was spectacular; when it was bad, we motor-sailed; when it was just okay, we engaged the propulsion system and developed the concept of the ‘free ride’ (see below).

The last three days of leg one were spent riding a hankey-yankee in winds of 20-plus knots and 25ft seas, so using the electric propulsion system was unnecessary until we got to the St George’s channel where we had plenty of propulsion power to get us into the customs dock and back out to the anchorage without a drop of sweat.

We’d covered 999 miles in 13 days, three hours, and 30 minutes.

To the Azores

 Dena finishes tidying up the wiring of the lithium iron phosphate battery pack and covers the terminals in sheets of clear Mylar

Dena finishes tidying up the wiring of the lithium iron phosphate battery pack and covers the terminals in sheets of clear Mylar

We left Bermuda after a two-week sojourn with a good 10-day forecast. We made careful note of where the wind was forecast to die off and where it would get stronger than we’d prefer to see, and we sailed for the sweet spot along the north edge of the Azorean High.

For a solid week in the middle of the trip, the high overtook us most mornings and dissipated most evenings so we could sail in the dark and only motor when the sun was overhead.

The only time we ran our propulsion battery system down to worrisome levels, we’d become caught in a counter-current and allowed it to push us back to a point where we could make enough north to get around it.

Our salt-fattened self-steering lines began to fray between the Monitor windvane’s body and the turning blocks on the cockpit coaming, so we quick-fixed it and continued on our merry way. Twice, the wind died so thoroughly as to entice us to swim. In the main, however, we kept sailing and motoring.

By the time we neared the Azores, we had long since stopped worrying about how long the trip would take. As long as we were making way and making water, we’d be fine.

Retro inspiration

Cetacea anchored off Velas, São Jorge, in the Azores

Cetacea anchored off Velas, São Jorge, in the Azores

On our first boat in 1999, we expected to use the diesel only for getting into and out of marinas. It’s nice to have goals, right? Our fondest hopes were to gain skills and confidence until we could be like those storied sailors-of-yore on engineless epics.

Instead, we’ve embraced the electric motor’s capabilities to set us up on really nice angles, to fill our sails gently when the winds are light, and set the anchor with complete confidence in that quiet dream anchorage. We are no longer testing new technology and proving an ethical point of view.

We are simply using a trustworthy tool powered by an almost never-ending fuel source.

Turns out, the electric motor is some of the oldest technology on Cetacea. The first electric boat was launched in September 1838, a full 60 years before the first diesel engine was started.

If you think about it, our brand-new tech is actually a little bit retro.

Continues below…

The ‘free ride’

Dena's cat Beluga Greyfinger inspects the LiFePO4 cells

Dena’s cat Beluga Greyfinger inspects the LiFePO4 cells

We have used the electric motor far more freely than we ever did the diesel. The sound of the diesel sent our cat, Beluga Greyfinger, into hiding.

The vibration loosened random fasteners and the stink permeated the boat. Starting the diesel engine was a frustrating disappointment, every time, and we avoided it assiduously.

Conversely, the electric motor is always ready. It’s quiet and never fills the cabin with exhaust fumes. There’s no need to discuss or overthink whether it’s the right time to use it.

As we learned its strengths, we discovered that the quiet boost of our electric propulsion is a tremendous boon in a wide range of sailing situations that do not freak the cat out.

At first, during the shakedown, the motor did not come into play until setting the anchor and we celebrated how well it worked.

We weren’t using very much power, though. On the third day, we motored full speed (with the main up) to draw the battery down and test how quickly we would recharge.

In the Floridian tropical heat, we got an over-temperature warning but quickly ramped the rpm back and the alarm went away.

We went back to a usage pattern more typical of our diesel days and had no more trouble in Florida. On the ocean, we could run the motor lightly to make faster, more targeted tacks and stick closer to the wind than usual.

We began engaging the motor anytime a benefit was even suggested and ended up leaving it switched on but disengaged most of the time.

Once we got to the Horse Latitudes, famous for its doldrums, we discovered that a little push set us up for an almost perfect angle to the wind and waves, as long as 2.6 knots was an acceptable speed. And it always was.

With no land for visual aids, 2.6 knots feels similar to 5 knots so who cares?

We evolved the true Free Ride.

Beluga Greyfinger surveys the anchorage from atop the boom

Beluga Greyfinger surveys the anchorage from atop the boom

In no more than four or five knots of true wind speed, with the mainsail double-reefed to reduce slatting, the electric motor only needed to turn the prop at 500-600rpm to improve our motion through the water.

At a draw of less than 0.2kW and an input of almost 0.35kW in solar, we were rolling along free with a slight boost in the electrical piggy bank to keep the smiles on our faces. Our speed waxed and waned with the swirling currents of the mid-Atlantic 30s. As the sun went down, the maths changed.

Inevitably, so did the weather conditions. More often than not, we got an increase in wind around sundown and disengaged the motor until the wind failed the next morning.

Our power use and production were so balanced that we eventually cross-connected the propulsion pack with the house batteries every day when we used the watermaker.

We logged the state of charge for each of the three batteries each day. The propulsion numbers make for boring reading, hovering near 100% until day 16. The wind never filled in for the night and our speed dropped in a countercurrent.

By noon, we’d motor-sailed east, west, and then north looking for a way out and our propulsion battery was down to 42%, or 96.6Ah. This was the big test and the system proved itself. We made only 26.8 miles over those 24 hours but we got ourselves out of trouble and kept making our way toward our destination.

Over the next eight days, the state of charge increased back to full. We used two-thirds of that capacity in our final push for Horta and arrived looking forward to our next voyage’s free rides.

About the author

Dena Hankins

Dena Hankins

Dena Hankins and her partner James Lane moved aboard their first yacht in Seattle, Washington, in 1999. They live and travel on their 1984 Baba 30, Cetacea, with their cat, Beluga Greyfinger. Hankins is a novelist and short-story author who writes best in quiet anchorages. Lane is an author, photographer, and storyteller.