Famous YouTubers Sailing Uma double up on Oceanvolt electric saildrives
Uma, the 36 foot hero of one of YouTube’s most popular sailing channels, is having a second Oceanvolt ServoProp electric saildrive installed by owners Dan Deckert and Kika Mevs as they make the boat totally fossil-fuel-free (FFF).
The Sailing Uma channel has 433,000 subscribers who avidly follow the couple’s adventures sailing, living aboard and maintaining / refitting the 1972 Pearson 36 they bought in 2014 because they ‘craved experiences over possessions, freedom over convention’. They wanted to live minimally and travel indefinitely and chose to write their own story and live aboard a sailboat.
First thing: diesel out, electric in
One of their first decisions after buying Uma was to replace the diesel motor with electric, because ‘neither one of us really liked having a tractor engine in the middle of our living room’. (Many of the quotes in this article come from the Sailing Uma Episode below: Developing the Ultimate Electric Propulsion System (After a Decade of Testing) | Step 442.)
Just out of college and lacking funds, they put together the first electric drive for Uma by ‘combining some golf cart parts, a golf cart controller and golf cart batteries…and for the first two years when we sailed around the Caribbean that’s all we had to push our boat.”
Hearing them describe that motor and system in the video is kind of tragically comic: “it was capable of moving our boat for about 15 minutes…the solar we had was enough to run our house loads but not really enough to charge up our battery bank…the solar and the whole boat was at 12 volts and the motor was at 48 and we literally had to rewire the battery bank in order to use the motor.”
See Uma’s entire journey from the tropics to the Arctic on the Sailing Uma YouTube Channel
After the Caribbean trek (where they visited Kika’s native Haiti to participate in the the Haiti Sailing Cup), they made their way back to Florida and got some lithium-ion batteries, which meant they could run the motor for longer if necessary…kind of. “The motor would overheat long before the batteries were dead” says Dan, “and we still didn’t have any regen so we still had a hard time charging our batteries back up if we used the motor a lot.”
Ed’s Note: ‘Regen’ refers to regeneration (sometimes called hydrogeneration), the ability of some electric boat motors to convert to an electricity generating turbine when the boat is under sail and use that to recharge the battery.
Undaunted, they sailed up the US coast, explored some of Canada (Dan’s home and native land), then set off across the North Atlantic, all with the same DIY system.
On arrival in the UK they were able get their hands on a used Oceanvolt electric ServoProp saildrive with award-winning regenerative capabilities. Uma 1.0 became known as Uma 2.0, and they sailed her all around the UK, the Netherlands and up the coast of Norway and beyond the Arctic Circle to Svalbard, at 70º N.
On Uma 3.0 everything will be electric
It was after a tour around the Mediterranean in 2021 that they realized they had sailed over 28,000 miles and the almost 50 year old Uma was starting to show some wear and tear.
As it says on their site “That’s when we made the decision to do something we should have probably done from the start: strip her down to the bare hull, reinforce her structure, and completely rebuild Uma from the ground up. “
Part of the rebuild was structural, part was redesigning all of the living spaces the way they’d dreamed of for years, and part was to make every aspect of the ‘new’ Uma 100% electric. While Kika and Dan had never used any fuel to propel Uma (although a small gas generator was on board for awhile), they did use wood for heating, alcohol for cooking and had a dinghy with a small petrol motor. On Uma 3.0, everything is going to run on electricity, which is where the second Oceanvolt ServoProp comes in.
On the face of it, many people assume that having two electric motors means the boat can go twice as fast while under motor power. First of all, it’s not like going faster is something Kika and Dan are concerned about – one of their mottos is “we’re in no hurry to go anywhere, ever.” More importantly, it’s not how displacement hull vessels work. There is a maximum hull speed related to the length of the waterline of the vessel, which is somewhere around 8 knots for Uma.
Long experience has shown them that it takes about 8 kW of power to move Uma at the speed they like. Whether the boat has 10 or 15 or 30 kiloWatts available is immaterial, they still need only eight. They might split the output between those 8 kiloWatts, but that amount of power will always move the boat at the same speed (depending on conditions).
Two Oceanvolt electric saildrives are two turbines
On the other hand, when it comes to regen, having two motors is basically having two turbines – under sail power you will generate twice as much electricity. For an example, at a sailing speed of 8 knots, their original Oceanvolt ServoProp 15 generated about 1 kiloWatt of power. Adding a second means that the boat can now generate 2 kW. (As an aside, for larger boats with higher hull speeds, the amount of electricity generated goes up at a faster rate than the speed of the boat: 7-8 knots generates 1 kW and 11-12 knots generates 3 kW).
With the additional electric load of the new Uma 3.0, that double regeneration will be extremely valuable – and necessary. Kika and Dan also have plans to add significantly more solar panels and some wind-driven turbines, but the Oceanvolt electric motors will be the main source of electricity.
Read: Oceanvolt Servoprop 25 wins big at DAME Awards
Dan, Kika and Uma have been associated with Oceanvolt since they got their first motor in the UK and have been a key partner in testing the software that controls blade angles of the variable pitch propeller (The Oceanvolt ServoProp saildrive is the only controllable pitch saildrive on the market). With the new system each motor/turbine can be optimized individually, for forward thrust, reverse thrust, and hydrogeneration.
There are a couple of other benefits of having two motors / turbines.
The first has to do with manoeuvrability. The two motors will be on each side of Uma’s hull, about a metre and a half apart, which means that they can be used instead of a bow thruster when docking. Kika says “I’ve always been a bit nervous about docking Uma because she’s so susceptible to the wind and you have the prop wash and you never know what the bow’s going to do but this will be like docking a catamaran, way easier.”
The other big advantage is simple redundancy. Each of the motors will have their own separate battery banks and battery management systems, so if there is a software issue or a line gets caught around the prop or anything else untoward happens, the second motor / turbine is there for backup.
If you are at all interested in converting your sailboat’s combustion motor to electric, or buying a new sailboat with electric propulsion, the Sailing Uma YouTube channel is a great source for practical information presented in a very personable, entertaining way – and with real life experience to back everything up.
There is no final word yet on when Uma 3.0 will be ready to set sail, but there there are new episodes on the YouTube channel every couple of weeks, so we can literally say ‘stay tuned’.
Sailing Uma website Sailing Uma YouTube Channel Oceanvolt
Check out Oceanvolt motors for sale in the Plugboats Marketplace
