All the power in the world
by John Curnow, Global Editor, SailWorldCruising.com 28 Oct 11:00 PDT
There is a particular kind of luxury that matters on a cruising yacht. It has very little to do (read nothing at all) with polished timber, acres of plush upholstery, or the number of drinks that can be put on ice, but yes, they certainly do count in the right way. Like, say, when at anchor in an absolutely marvellous bay…
What we are referring to, is the type of luxury that gives confidence, eases the mind, and makes so many things possible without nary a consideration at all. It is living aboard properly, day after day, without constantly negotiating with the boat or fellow crew mates. It is tasks like cook when you are hungry, make water when the tanks need it, or wash clothes when they are dirty.
Modern living takes on a whole new aspect too, and this would be running the air conditioning when it is hot, and the heater when it is cold. Then there’s edit a video, upload it, charge cameras and computers whilst you’re at it, keep Starlink alive to provide for not only communication with friends and family, but also research for your job and problem solving when things go a little awry. Of course, you’ll have to do it all again tomorrow, and why not do it without listening to the genset, or wondering how much diesel remains.
This is the very proposition behind Uma 3.0, the latest incarnation of Dan and Kika Deckert's 1972 Pearson 36. They have lived aboard Uma for 12 years, covered more than 30,000 nautical miles, and seen more than 30 countries.
They have taken an electric sailing project from Boston to Florida, the Caribbean to Norway and Iceland, making it to Svalbard, which sits at 74 to 81 degrees North. Their very-much-forthcoming Westabout circumnavigation is therefore absolutely not the beginning of an experiment. It is the next examination for a boat, a couple, and an electrical philosophy that they have already had more than a decade at sea with. Notably, in the early days, this is whilst they also taught themselves how to sail.
They are presently in the final throws of their third refit. This matters, because the present boat is not the result of two architects sitting down with a blank sheet, and then imagining what a self-sufficient cruiser might require. It is the result of living inside 36 feet for years, finding what failed, discovering what they actually used, learning what they could repair themselves, and then stripping the boat back again to make the next iteration better.
SV Uma not only has new, twin electric propulsion (it started out life with a forklift motor powering her along), but also expanded solar on the new fixed pilothouse, and a massive 50kWh of storage, which would be double the requirement. The interior was totally stripped and parts re-glassed. Along with a new and slightly taller rig (with a larger sail plan to boot), the whole vessel is basically the same mass as it always was.
As for the circumnavigation, Dan says, "To us, it's more about proving that you can cook, bake bread, make sumptuous meals, have air conditioning, do your laundry, make water, and live comfortably with a fully (and totally) electric boat. We know we can do it with zero fossil fuels, and now we want to see what it's like to get all the power.”
Dan and Kika also make a crucial distinction. Uma is a sailboat first. Her sails provide the primary propulsion and, if the electrical architecture were switched off, they are very proud to point out that they could continue under sail with analogue navigation.
Their circumnavigation is not an attempt to replace sailing with batteries. Rather, it asks whether the domestic and technical life of a modern liveaboard can be supported without diesel propulsion, a diesel generator, gas for cooking, or petrol for the tender.
Solar, hydro regeneration (from both screws), and stored electrical energy have to cover propulsion when required, navigation, communications, watermaking, cooking, climate control, and the considerable electrical appetite of two professional filmmakers. A quick note so that it does not become a speed hump, we’ll deal with SOG loss due to regen a bit later, but do remember that SV Uma is a displacement craft that does 5-7 knots for most of her life…
A home that also crosses oceans
SV Uma’s origins are almost comically modest when compared with the present specification. In 2014 when the then recent graduates bought their boat near Boston, neither of them had any sailing experience. The 50-year-old Pearson came with a diesel engine that did not work, and replacing it conventionally was beyond their budget. Sailing it away was not an option either, so it was trucked to Florida, so that work could begin in earnest.
So, they put a second-hand forklift motor in, along with a few batteries. At the time, there was not even a shore-power cord. Once seaworthy, they took off for the Caribbean, where they not only depended on solar, but importantly, taught themselves to sail, along with general seamanship, and also learned what Uma needed. Do note that this first adventure meant they had steering, sails, and an anchor, but no head, nor stove, let alone chartplotter and autopilot.
As Kika says, ”We spent the first two years in the Caribbean learning how to sail, and learning what we needed. We kind of upgraded the boat along the way. It was afterwards that we undertook what we call the first real refit, which lasted us the next six years. The result is that we now have so much more experience, and we know exactly what we want out of this boat.” Point to stress here, because as it all carries on, they remain full time liveaboards.
Experience has changed their brief. Their high latitude sailing up North in the Arctic culminated in a hard Atlantic crossing. It also changed the relationship between crew and boat. Kika describes reaching the point where “…Uma became the weakest link. We had grown more capable and more ambitious, but no longer felt the existing structure and systems were sufficient for the next programme. Buying a new boat would have cost vastly more and introduced debt, which was not what we wanted.” Instead they gutted the Pearson and rebuilt the boat they already understood.
"The running joke is that we're taking out fat and we're putting on muscle, even though it's going to weigh the same when we're done," added Dan.
The new 50kWh heart of Uma 3.0
At the centre of the new boat are two, independent 25kWh lithium iron phosphate (LiFePO4) battery banks, giving 50kWh of total storage. The banks comprise ten Victron batteries in total, with duplicated battery-management architecture. Dan's point is not simply that 50kWh is a large number on a 36-footer; it is that either half of the installation is intended to support the entire boat. One bank can carry all normal loads, leaving the second as genuine redundancy, rather than capacity that must always remain connected for the vessel to function.
They deliberately chose proven lithium iron phosphate (LiFePO4), rather than pursuing newer battery chemistries, simply because they were newer. Packaging mattered, but so did transparency, and out-in-the-field repairability. Their Victron batteries are deliberately simple at the cellular level, with temperature and voltage sensing, rather than an inaccessible software-controlled safety system sealed inside each battery. The external BMS provides protection and pre-empts faults, but Dan values knowing that, with the appropriate knowledge, the battery itself remains comprehensible and accessible.
This same philosophy runs throughout the system. Most of the electrical architecture is Victron, integrated with the Oceanvolt propulsion equipment. Cerbo GX and Signal K provide the software layer, and the open backend access Dan wants for monitoring and adaptation. Yet the cleverness is not allowed to become a single point of failure. They designed the system, specified the components, drew the diagrams and installed it themselves. Offshore, that in-built knowledge is also part of the redundancy.
Dan commented, “It means we know it, inside and out, and backwards, too! We also know that if there is an issue, we can fix it or bypass it until we can get on Starlink, or our sat phone to contact somebody to help us troubleshoot it.”
The propulsion side is also equally deliberate. Uma now has twin Oceanvolt electric drives, each with a 16-inch propeller, and the ability to regenerate while sailing. That means up to 1kW of regeneration under sail, so Dan and Kika expect the combination of twin regeneration and the 3kW solar array to make the boat an energy producer whenever conditions permit. Their previous single-drive installation has given them five years of real data on regeneration, from which Dan says “…the speed penalty has been difficult to isolate from normal variations in sea state. In stronger reaching conditions the old motor could generate 500 to 600 watts without a measurable reduction in boat speed that we could confidently attribute to regeneration.”
The potential daily production is substantial. Dan puts the combined upper potential of the two motors and solar at around 30 to 40kWh in a day under favourable conditions. That is not a promise of a fixed daily yield. Rather, they understand clouds, sailing speed, latitude, course, and sea state all dictate the actual number. What matters is the scale. They are designing around enough generation to live not just normally, but well.
There can be no austerity regime on Uma, where every cup of coffee is an energy-management decision. They have to make and upload YouTube videos, for that is their livelihood. This is the point of this piece. They live in the modern, power hungry world, just happen to do it on a boat!
Larry (load) wins the day
Liveability can be proven, demonstrably. Proof comes in the form of fact, well before Uma even returned to the water. Once the new solar installation was operating in the Sardinian yard, Dan and Kika largely stopped relying on the unreliable shore power. Firstly, they ran the boat's air conditioning from solar and batteries. Then, when the yard supply failed, sometimes several times a day, they plugged their two, (40-foot) work containers into Uma and kept the 3D printer, laser welder, TIG welder, and other tools operating from the yacht's energy system. It has proven so successful that other tradies working away asked if they might tap into some of that power, as well. A parallel note here, for it is highly likely that there will be craft they come across along the way that will ask to raft up for either electricity or fresh water, or both.
Dan asks, ”If you want to run your air conditioning all night without running a generator, what is that worth to you? If you zoom out and look at the entire boat as a whole, electric's not any heavier than diesel, but it's the capability that you want your boat to have. There's always going to be trade-offs in expense versus weight versus capability. These manifest in size of vessel, type of vessel, boat speed, and overall value of craft.”
For Dan and Kika, capability means living aboard without making the technology the dominant feature of every day. It means running heat when it is cold and air conditioning when it is hot. It means making fresh water whenever it’s needed, and cooking a ‘normal’ substantial meal, rather than proving an energy point by living on freeze-dried food, just like an ocean racer.
Critically, it also means powering Starlink, the cameras, data storage, computers and editing equipment that underpin their livelihood. Sailing Uma's videos are not merely publicity for the voyage; after 12 years of documenting their life, filmmaking has become their principal income stream. The boat therefore has to power the work that pays for the boat.
This introduces a demanding load profile. Video production requires cameras to be charged, and computers to spend long periods rendering and editing. Connectivity has to remain available for communication, and most importantly, publishing. Dan estimates that filming can make a physical refit take two or three times longer, simply because every job also needs lighting, cameras, planning, story structure, and editing. Kika makes the economic loop explicit: producing videos about their life and refits allows them to share it and to continue funding it.
Dan added, ”If you understand how a 12-volt circuit works, you understand how our entire boat works, If you understand how to troubleshoot a 12-volt circuit, you understand how to troubleshoot our entire boat. In addition to the mass of the powerplant, and its fuel, we just don't need any diesel knowledge.”
The long way around, comfortably…
The planned circumnavigation gives their architecture (yes, pun intended) a suitably severe test. The intended route runs West from the Mediterranean (Gibraltar), across the Atlantic, then down to Patagonia and around Cape Horn, after which it is back up and into the trade-wind system across the Pacific, across the top Australia and into the Indian Ocean, around the Cape of Good Hope, and up the Atlantic Ocean once again. The nominal programme is around 12 months, driven less by record aspirations, than it is by the sequence of weather windows. Australia, with Darwin identified as a likely technical stop, sits roughly halfway through the programme.
Another important word that accompanies this whole saga is, cruising. Dan and Kika are emphatically not attempting a non-stop racing lap. They want the freedom to wait for a favourable system at Cape Horn, so as to anchor there, as well as film it, rather than simply survive it. Actually experiencing Patagonia is a key moment for these ardent explorers. They will adjust the route for weather, visa/Embassy constraints, and what they learn from the boat. Kika's Haitian passport adds another logistical layer, and the pair are realistic that not every desired stop may be available.
Kika quickly reminds us that, "I think the beauty of doing it as a cruising sailboat, as opposed to a race, is that we're not abiding to any specific rule. We have a route that we're journeying towards, but if the weather forces us to shift, we're not going to fight against nature. We're going to go with it.”
That freedom is also an essential aspect to the electric proposition. Dan says that, in principle, they can generate power indefinitely, provided they are not forced to motor halfway across an ocean to meet a commercial schedule. Their answer to a becalming is fundamentally a sailor's answer. Namely, wait, sail when the wind returns, and treat the auxiliary propulsion as auxiliary. Kika says going electric forced them to learn that lesson very early, and definitively, including coming up to swing moorings, for instance.
By way of emphasis, Kika adds, ”We meet a lot of sailors that whenever they have the first doubt, or the first hesitation, the first thing that they rely on is turning on the engine. I think it's more important for people to rely on their actual sails, than it is to rely on the auxiliary engine, whether that be an electric motor, or a diesel engine. That should not be your first default. It should be your sails.”
Equally, Dan and Kika are not saying everyone has to follow their lead with SV Uma. Kika is quite explicit that all-electric is not automatically the right answer for every mission. “A vessel spending a year in Patagonia, a commercial expedition boat carrying paying guests to Antarctica, or a yacht that must keep a fixed schedule may sensibly choose diesel, or a hybrid arrangement. Our frustration is not with those choices, but with blurred terminology and marketing that labels a vessel all-electric, whilst relying on a large diesel generator whenever the batteries are depleted.”
"We don't want to come across as if we're forcing people to follow our footsteps, as a result of our challenge, and our proof of concept. It depends on your purpose and usage, as well as where you are, and where you are going. There's so many options in between all-Diesel and all-electric, and ultimately, it’s a matter of what you want to prioritise,” said Kika.
What Uma is designed to prioritise is both unusually, and wonderfully clear. This is a home for two people who sail, film, build, and work aboard full time. They have had 12 years to discover the difference between equipment that looks desirable at a boat show, and equipment that earns its space after the thousandth night aboard. Three refits have allowed the answer to evolve from a forklift motor and a handful of batteries, into twin Oceanvolt propulsion, 3kW of solar, 50kWh of LiFePO4 storage, duplicated energy management, hydro regeneration, and an integrated electrical network large enough to run domestic comforts and a media business.
Their glorious circumnavigation will now expose all of that to heat, cold, salt, vibration, long passages, cloud, calms, strong trades, and the inevitable failures that do not appear on a wiring diagram. Dan regards that as the point. They could turn the batteries off and sail around the world, but it would prove very little about the system. The coming year is intended to find vulnerabilities, fix them, adapt the installation and discover where the practical limits really sit.
After 12 years, the remarkable part is not that Dan and Kika have made an old Pearson electric. They did that at the beginning. The remarkable part is how far the y have pushed the envelope along. SV Uma 3.0 is no longer asking whether an electric motor can push a sailboat into harbour. It is asking whether a cruising yacht can produce enough of its own energy that two people can live, work and cross oceans without organising their lives around fuel.
On completion, the answer will be a categoric ’yes’, and the most persuasive evidence will not be a headline number for range, or a record around the planet as the first, genuinely all-electric craft to perform a circumnavigation.
Peculiarly, it will be far more ordinary, and therefore far more relevant to cruising sailors, for it will be bread coming out of the oven, clean clothes coming out of the washing machine, fresh water in the tanks, an air-conditioned cabin, footage rendering on the computer for the next big upload, and two battery banks quietly filling again whilst Uma sails on.
All of the above is total on board liveability, and I am a firm believer that it will prove to be the most interesting performance figure of all.
Sometime between the end of November and the first week of December, SV Uma 3.0 will take off from Gibraltar. You can follow Dan and Kika via their website, where there are links to all of their socials, and crucially, their YT Channel.
If you want to see what is happening in the other Hemisphere, go to the top of the SailWorldCruising home page and the drag down menu on the right, select the other half of the globe and, voila, it’s all there for you.
Finally, stay safe, love your yachting, and be respectful to oceans and other sailors alike.
John Curnow
Global Editor, SailWorldCruising.com