Daydream believer
Well-known member
Of course, which takes the hybrid even one step further.You don't motorsail?
I did not realise I was so " green".
Thanks for reminding me
New boat, conventional diesel or diesel hybrid?
- Thread starter doris
- Start date
I did not realise I was so " green".
Thanks for reminding meAdios
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The art of selling by turning a limitation into a bonus. And "we're helping people be sailors and not diesel mechanics" ? Looks good to me though but i can't see it working for charter companies. I didn't hear them mention range on electric did I miss that? I heard him say "the electric community" though ?
Flemming91
New member
Judging by the practicality, I would choose a diesel
TernVI
Well-known member
Does that mean you'd be running a noisy stinky diesel just to cook?
I think you are probably wrong about the efficiency. The diesel part of a generator will be a little more efficient than the boat engine, but the conversion losses will counter that.
A 33ft boat in Biscay is potentially a very wet environment. You need to think twice about relying on electrics with more than a few volts. As soon as you see a real storm and things get a bit damp below, it will probably all shut down.
dunedin
Well-known member
Not sure i would agree with that, other than the more expensive to buy bit (which is a huge factor).
Other than day sailers, it currently only really makes sense when looking at a new build 45 or so foot long distance cruiser.
Today that will typically have a large Diesel engine, plus a diesel generator, plus at least one Watt&Sea hydro generator - as well as solar.
Replacing that with a single diesel generator and one or two electric saildrives (with regen capability), plus a large battery setup, arguably makes for a simpler system ultimately to maintain. And electric drive motors are a very proven and simple technology.
However, it is true that to be efficient, all that lot will be microprocessor controlled - including the battery pack itself. So if anything does break won’t be a case of oily spanner fixes.
And one thing I have yet to get clarified is what happens if a large 100kWh suddenly gets inundated by salt water (eg due to a collision with underwater object). Been a very small number but very serious car battery fires after a rare crash combination. In theory the battery management electronics should protect the batteries from fire, but will these electronic safety features themselves fail if immersed in salt water? Mid ocean is not the place to discover the answer to that super fire risk question!
Tranona
Well-known member
youtube.com/watch?v=jpAnGJpcnQU
Pretty much like my benchmark for south coast cruising like I do. Look at holiday cruising logs and many will see that sort of 75/25 sail/motor mix and overnights in a marina. If you are prepared to work the tides and only sail with good winds the Sadler example would just about work. However like early electric cars, range anxiety would kick in. Nothing as comforting as knowing you have many hours of reliable diesel power to get you past headlands or back in time for work.
Vague on range, but probably 60 miles+ on fully charged bank, which begs the question of recharging as regeneration will not make much of a dent in that. So mains recharging seems inevitable. I could see this working for charter boats in Croatia where the boat hails from as they do have cruising areas with well spaced marinas and reasonable sailing winds. A week of sailing like in the video (without the rain) with an hour or two motoring and 4-6 hours sailing and a couple of overnights on shorepower could work.
Pretty much like my benchmark for south coast cruising like I do. Look at holiday cruising logs and many will see that sort of 75/25 sail/motor mix and overnights in a marina. If you are prepared to work the tides and only sail with good winds the Sadler example would just about work. However like early electric cars, range anxiety would kick in. Nothing as comforting as knowing you have many hours of reliable diesel power to get you past headlands or back in time for work.
Adios
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Judging by this installation
The ability to regenerate electricity is critical of course and the salesman here is claiming this boat already makes sense for "off grid" extended cruising, which it would if there was enough battery capacity for a decent range and if that could be recharged quickly. He said a couple of hours motoring would be recharged after 4 hours sailing, which gives a to be take with a pinch of salt guide anyway. If true and if in future the range could be taken to 100 miles motoring on calm days and recharged in a few windy days that would be plenty for nearly everyone.
The installation of the control units was about waist height so things would already be pretty near lifeboat time before thats an issue.
This new all electric boat has gas for cooking, must be a good reason they didn't use electric.
Buck Turgidson
Well-known member
Energy density. It’s the reason the maths don’t work for electric boats and if you add cooking to the list of loads you just make things much worse.
the solution is a very large capacity battery bank but that comes with the problems of weight and volume. The obvious solution is to replace the ballast keel with equivalent mass of battery but there are lots of engineering problems to solve if you do that.
lustyd
Well-known member
Yes, the range between stops is infinite miles assuming nothing breaks. Considerably better than diesel.
JumbleDuck
Well-known member
I think that hybrids probably do have a future in boats. This is why ...
There are basically three use cases for auxiliary propulsion. One is for short trips in and out of harbours or marinas. Ten minutes to half an hour, say. One is for long distance trips when there is no suitable wind. The last is a for bit of extra oomph to punch a tide or get round a headland.
Current setups are generally inefficient at meeting these needs. A big diesel engine will do the quick punch fine but for longer trips will be much too big (a 40hp yacht auxiliary probably rarely runs at much more than 10hp) which isn't good for it and wastes a lot of space. It's also a nuisance to fire up for a short trip out of the marina and that doesn't do it much good either.
So ... hybrid. A 20 hp diesel with a 20hp electric motor can be used electric only to get in and out of marinas, diesel only for long trips or diesel + electric for mistimed trips through the Dorus Mor. Even with the motor it will take up less room that the diesel it replaces. The downside, of course, is that for half an hour of full electric power you need 650Ah of available 12V battery capacity, which at the moment is either heavy (lead-acid) or expensive (lithium-ion). However, the cost of Li-ion is falling year on year.
The real killer for now, I think, is that the hybrid drive unit would be expensive because the marine market is small. However, if other uses appear in other sectors prices will come down. After all, small marine diesels are only affordable because of the quillion forklift trucks and refrigerated trailers out there.
There are basically three use cases for auxiliary propulsion. One is for short trips in and out of harbours or marinas. Ten minutes to half an hour, say. One is for long distance trips when there is no suitable wind. The last is a for bit of extra oomph to punch a tide or get round a headland.
Current setups are generally inefficient at meeting these needs. A big diesel engine will do the quick punch fine but for longer trips will be much too big (a 40hp yacht auxiliary probably rarely runs at much more than 10hp) which isn't good for it and wastes a lot of space. It's also a nuisance to fire up for a short trip out of the marina and that doesn't do it much good either.
So ... hybrid. A 20 hp diesel with a 20hp electric motor can be used electric only to get in and out of marinas, diesel only for long trips or diesel + electric for mistimed trips through the Dorus Mor. Even with the motor it will take up less room that the diesel it replaces. The downside, of course, is that for half an hour of full electric power you need 650Ah of available 12V battery capacity, which at the moment is either heavy (lead-acid) or expensive (lithium-ion). However, the cost of Li-ion is falling year on year.
The real killer for now, I think, is that the hybrid drive unit would be expensive because the marine market is small. However, if other uses appear in other sectors prices will come down. After all, small marine diesels are only affordable because of the quillion forklift trucks and refrigerated trailers out there.
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lustyd
Well-known member
Your logic is spot on, but it reads very similar to the list of reasons pure electric cars would "never catch on" 10 years ago. People have only just really started trying electric boats for leisure use so expect them to improve rapidly over the next 10 years, especially as money starts to change hands
pvb
Well-known member
I don't understand this comment. How much of a nuisance is it to press a button to start the engine, then press a button to stop it?
No, you'd need much more battery capacity for a 20hp electric motor. It's likely to run on 96V and draw 150A or so.
lustyd
Well-known member
Of course, we could see things like prop design change drastically to accomodate motors which can deliver all of their torque all of the time, so it's possible we might not even need equivalent power to achieve the same results. We may also see props designed to harvest maximum power under sail. Everything about current design is based on the compromises necessary to accomodate a diesel engine and its many and various failings.
doris
Well-known member
Since this option was only raised a few days ago my ignorance is huge. The info from everyone on this thread is terrific, I thank you all.
Please don't hold back should anyone else have any input, all much appreciated.
does seem that electric cooking is out but I have always fancied the idea of a generator sited in the perfect position for weight distribution and no gear box. With battery technology improving so massively to have the ability to motor for and hour or two is a bonus and the efficiency of the likes of Watt&Sea is impressive.
Also the damage done to diesels when they are only used to get out of the harbour whereupon the sails go up and the engine goes off is significant.
Please don't hold back should anyone else have any input, all much appreciated.
does seem that electric cooking is out but I have always fancied the idea of a generator sited in the perfect position for weight distribution and no gear box. With battery technology improving so massively to have the ability to motor for and hour or two is a bonus and the efficiency of the likes of Watt&Sea is impressive.
Also the damage done to diesels when they are only used to get out of the harbour whereupon the sails go up and the engine goes off is significant.
TernVI
Well-known member
People repeat this as some sort of statement of faith, but in my experience a lot of the time the engine is running for plenty long enough to reach full operating temperature. Maybe there are some marinas located so you only need the motor for 5 minutes, but I don't know them. Mostly the motor runs for 20 minutes or more while people get clear of the harbour and faff with sails.
As for the idea that it's bad for an engine to run at a fraction of its power, most cars will do 200k miles, on average they will be running at what? 15% of rated power and half the time under 100%.
How many thousand repetitions make a truth on the interweb?
Possibly the big picture is that dieseling around in a yacht at 10mpg will not be an acceptable activity before very long.
We could be looking at short range power just to get off the pontoon etc. A big Torqueedo and a couple of kWh of battery?
No generator, no complication.
JumbleDuck
Well-known member
More hassle (maybe including turning the water on?) than an electric. OK, not the biggest deal in teh world, but electric is easy. I've seen it.
Remember that I only suggested 30 minutes on electric. 20 hp = 15 kW. 15 kW for half an hour = 7500WH, which is 625Ah at 12V. Or less at 96V, or course, but that's wiring, not battery size.
JumbleDuck
Well-known member
True, and of course that's what car engines are designed for, including regular blatts of full power.
Yup. I think it's going to be worse for the big motorboat market, though being in general rich they will inevitably be protected longer.
pvb
Well-known member
Your maths is too simplistic. Ever heard of Peukert?
Bobc
Well-known member
Someone I know delivered an Oyster a few years ago which only had electric for cooking with no gas on board. They used to run the genset to run the cooker when on passage.
I would have thought that for the type of cruising you want to do, it would be perfectly feasible to have an electric drive unit and a genset (for cooking and charging batteries), and with the regen motor unit and maybe a watt&sea and some solar, I can't see you ever getting stuck.
The cost is going to be considerably more than sticking a donk in, but if you want to have electric for cooking, you will need a genset, so you're half way there already.
JumbleDuck
Well-known member
My maths is superb. You need to take 650Ah out at 12V. How you achieve that is a different matter. Clearly you'd need a lot more that 650Ah if you were using lead acid, but not if you were using Li-ion.