Although there are some ferries and commercial boats that use a multi-hull design, the most recognizable catamarans by far are those used for sailing. They have a number of advantages over monohull boats including higher stability, shallower draft, more deck space, and often less drag. Of course, these advantages aren’t exclusive to sailboats, and plenty of motorized recreational craft are starting to take advantage of this style as well. It’s also fairly straightforward to remove the sails and add powered locomotion as well, as this electric catamaran demonstrates.
Not only is this catamaran electric, but it’s solar powered as well. With the mast removed, the solar panels can be fitted to a canopy which provides 600 watts of power as well as shade to both passengers. The solar panels charge two 12V 100ah LifePo4 batteries and run a pair of motors. That’s another benefit of using a sailing cat as an electric boat platform: the rudders can be removed and a pair of motors installed without any additional drilling in the hulls, and the boat can be steered with differential thrust, although this boat also makes allowances for pointing the motors in different directions as well.
In addition to a highly polished electric drivetrain, the former sailboat adds some creature comforts as well, replacing the trampoline with a pair of seats and adding an electric hoist to raise and lower the canopy. As energy density goes up and costs come down for solar panels, more and more watercraft are taking advantage of this style of propulsion as well. In the past we’ve seen solar kayaks, solar houseboats, and custom-built catamarans (instead of conversions) as well.
Simply using the wind is way more eco-friendly. I understand why it’s desirable but I’m against the concept of making things less eco-friendly than when they started.
I never thought about this before but it kinda makes sense. Propellers do disturb the natural flora and fauna more than sailboats would. Aren’t there computerised sailboats which can adjust the mast direction and everything?
There’s also the ecological impact of manufacturing the electornics, motors, solar panels etc. Far more damaging.
there is also the ecological impact of armchair ecologists blabbering on hackaday…
I’m looking forward to your ecological footprint analysis of producing sailing gear vs electric gear. As handwritten manuscript will be accepted as I cannot phantom you using a computer, let alone one connected to the internets.
There are rotor sailboats that use the magnus effect instead of sails. A few large cargo ships use them to supplement their diesel engines to reduce emissions an fuel costs without the labor of keeping sails trimmed.
“Aren’t there computerised sailboats which can adjust the mast direction and everything?”
Rigid Wingsails like the Walker Zephyr can run on autopilot. Their single manned “fly by wire” capability is one of the big advantages over fabric sails.
https://youtu.be/yZhRwgjgVEg?si=vq57mOg2IpEtKGFv
How many sailing ships have you seen in narrow rivers/canals like this one? Not to mention, the riverbanks are full of trees shielding the wind (if there is any).
And low bridges to pass under. I saw a sailing club in Cookham on the Thames and they were sometimes having to tac every second almost. The Thames is a lot wider than most canals. So trying to sail up a canal really isn’t practical even with the most pointy boats.
I think we are missing that this boat is now accessing water ways that it previously could not
I tried that once. Lots and lots of tacking back and forth with very little headway to show for it. People on the shoreline laughed at us. I didn’t try it a second time
There’s multiple good reasons we don’t use sails these days – and for a lot of inland traffic they were never a good idea – canal barges used to be pulled by horses before steam and then internal combustion came along.
The masculine (or feminine) urge to buy a boat, put enough solar panels on it to make the boat run forever and have enough spare power to run a water desalinator and a stove etc. Then I will travel the world’s ocean, subsisting on seafood that I catch on the way. Seeing new places and meeting new people and probably having to fight pirates.
Realistically I’ll spend another evening on my couch though
A fine plan, except you’ll quickly start suffering from scurvy.
Not romantic troublemakers as portrayed by Johnny Depp, but people with average IQ of 60, armed with rusty AKs and RPGs. I think I’d rather take a prostate exam than get anywhere near them.
Well if you are meeting new folks all the time it rather implies stocking up on your lime juice when you pull into port shouldn’t be a massive task, and one barrel of that would go a very very long way to preventing scurvy.
Also has to be said pirates these days are very very unlikely to bother with such a small boat that doesn’t scream ‘I’m a billionaire out on a jolly’ – just no money in it…
I do wonder how well flexible solar panels would preform if they were used as a sail, something semirigid, similar to what you might see on a surfboard, perhaps. [ I don’t pretend to know how to surf. ] No doubt probably a poor compromise on performance for both methods of propulsion.
solar cells themselves are semi flexible, they would not like (=break) it to be mounted on a flexible sail. Mounted on sort of rigid wingsail would be no problem, but then you get the problem of stowing/turning off that sail when you don’t use it.
What about long “strips” of panels, that left-right fanfold to stow :?
Worked for a while on one of these boats, the concept was pretty solid, between wind, solar, batteries, backup generator, and a nice system to automatically adjust between them, it could move quite fast with surprisingly little generator use.
https://en.wikipedia.org/wiki/OCIUS_Technology#/media/File:Solar_Sailor.jpg
It made for a fun programming challenge at the time automating the sails for maximum energy in whatever form was available
I had the same thought. If not flexible, you could make them a rigid airfoil shape like some modern sail concepts use. Still probably a less-than-ideal design for both
Flexible solar panels is IMO a bit of a misnomer really – technically you can flex them, even a few times but repeated flexing as you’d get windsurfing is going to destroy them pretty quick IMO.
I’d suggest if solar sailing is the goal in mind you don’t want flexible at all, but very rigid, probably composite aerofoils with solar in them (and I think for added durability and simplicity I might go for thermal solar (thin pipes worked into the carbon fibre wing as you go seems easier to make a good strong aerofoil and energy capture surface) and leave the electric generation to regular PV on the hull or a Stirling engine powered by that heated fluid). A few decent fixed wings will catch the wind nicely, might even be more efficient that a sail – the tricky bit I’d suggest is stowing them when you don’t want to go anywhere and control of your speed.
I do a bit of recreational sailing. Mostly racing dinghys less than 20 feet in length, but bigger boats too. We’re starting to see even larger boats with electric or deisel-electric hybrid auxillary propulsion for when there’s no wind or manuvering is constrained. This is true for both displacement hulls and multi-hulls like cats. Results are mixed, but it looks like that’s the direction things are going. Electric drives are less about replacing sails and more about replacing that stinky, expensive diesel or the loud, gas powered outboard on smaller boats. The latter is very appealing to me because safely storing gasoline on a boat is annoying. I can see how the impact of props could be greather than that of sails. In a sailboat, dolphins will sometimes swim right up to me. It’s nearly silent and sailboats don’t usually plane off. They move along at their hull speed which disturbs things a lot less. That’s not so with most powerboats.
I love the idea of not having to refuel.
How far and often can you travel in good weather? Say – every weekend for a few hours, and recharge during the week? Or 3 hours per day, every day with nice weather?
haha the whole point of a sailboat is that you can travel infinity in good weather and bad without refueling. For a weekend outing the couple hours of into and out of the marina is sufficient.
I apologize for being “that guy,” but this post is an extreme example of a trend that’s been bothering me for some time now. Using the same phrase in adjacent sentences is lazy writing and poor style, and it seems to occur frequently in HaD posts. This particular post uses the phrase “as well” no fewer than EIGHT times over the course of three brief paragraphs. If authors would just take a moment to read what they’re about to post, redundancies like this (along with various typographical errors and misstatements) should be apparent, and simple to remedy.
/rant
A lot of lake, canal and small river can be the playground for this type of unit. Already using 2 electric troller motor for restricted aera, i’ve tried in canals and work pretty well . I’m logging the sun power to estimate the needed solar panels for direct consomption for an unit like this one equiped with living needed structure.
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For this one, i like the idea, and the fact it’s an usuable real thing, but way too much hull for a two seater.
Ah and i should have mentioned this give some performance numbers on a real thing. Really good thing.
Haven’t clicked it, but is this Tech Ingredients?
Nope, but wasn’t he working on this a few years back?