Electric Pod Drive

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HunterWanderer

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I'm thinking of fitting a pod drive ( www.torqeedo.com/en/products/pod-drives ) to my 1948 27ft 3 ton Norfolk Broads sailing cruiser.
Does anyone have any experience of these.
Ive got a Bison 100lb Outboard at the moment which is OK but a bit short of power and the brushes have just worn out. Ive got 6 100 AH AGM batteries.
What does the panel think?
 
I really, really want this and other similar systems to be a success.
When my yanmar expires I plan to so the same but hoping to high heaven that the price drops as right now its hard to justify.
 
Javelin said:
I really, really want this and other similar systems to be a success.
When my yanmar expires I plan to so the same but hoping to high heaven that the price drops as right now its hard to justify.
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You will have to wait a very long time unless you are prepared to have a usable range of only a very few hours. Suggest you (and the the OP) look at the specification before you get excited.

Does not matter what the costs are or how they reduce (and there is no sign of that) you cannot with any battery technology available or on the horizon store enough energy to get more than a few hours range at cruising speed (less than 5 even with the smallest pod and biggest battery) without recharging. Nor is there any practical way of recharging on board unless you fit a generator - which takes you back where you started.
 
I'm not quite as black and white as Tranona as if you have a WattnSea water generator and you are using sail power, or are generating from the pod, and have a decent solar display (needs lots of space) then you do have another way of recharging the batteries. But if you are pottering about somewhere with light winds in higher latitudes (with not much reliable sun) - then these recharging systems will not work.

One needs to think how often you put your engine on to get somewhere and how long you run it for - that's the issue in the way most people use their yachts today. Many engines are not auxiliary anymore but critical items - that diesel power would no longer be there - so you need be very patient - or you need a gen set.

If you are circumnavigating it offers attractions - but you still need the gen set.

There is a 50' cat being built now which is, or is going to be, hybrid to the extent that the galley will be electrically powered (no gas). The ambitions are blue water, circumnavigating. Huge solar display. As far as I can make out it will be state of the art when launched (and well out of the budget of most people - so possibly an unrealistic example) but it will be interesting learn what transpires.

I too want it to work (I hasten to add - I'm just an idle observer) - but view the project with some trepidation.

I have an involvement as with a focus on saving weight they have used the high tensile lightweight chain (galvanised G100) I have discussed on threads here to save some weight (and have 2 alloy anchors).

Jonathan
 
You simply cannot generate enough electricity reliably with solar, wind and water to keep pace with an electric motor. You stand a better chance with a large multihull because of the space to have panels and higher speed potential for water power (losing some of the speed!) in the tropics and intermittent engine use, although having to fit large batteries to store what little energy you can generate kills some of the performance and space saving of not having a diesel. Such boats are in a sense freaks as once you try to translate the technology to everyday use in monohulls in temperate climates most of the things that make electricity vaguely possible go away.

There are of course situations where electric power is perfectly viable for sailing boats. The OPs situation sailing on the Broads with regular daily access to shorepower is one and I am sure there are many possibilities on the European lakes, particularly as there are moves to ban iC motors altogether on some. Remember the ban on 2 strokes started in the European lakes. We already have many electric powered boats on our inland waterways and have done for over 100 years because their usage patterns are suited to electric.

The multihull you describe is somewhat similar to the Lagoon 42s that were built a few years ago for charter in the Caribbean. These had diesel electric propulsion with an 11kva generator in a locker on deck and an electric propulsion motor in each hull plus lots of batteries. The domestics were all electric - 2 fridges, domestic style cooker, electric water heating, electric winches etc. The generator ran any time battery capacity fell below 80% and could power propulsion motors directly to get maximum speed which was poor at 6.5 knots. Not a success. Too expensive, complicated, high maintenance.

So, lots of little niche areas where electric is possible and even desirable - there are many more I could quote, mainly in the commercial world, but just not for mass market small cruising sailboats (and by small I mean under say 70') - and even above that it has to be diesel electric or hybrid.
 
A good summery

I'd not be so dismissive of electricity from a water gen. We can produce 10 amps at 10 knots with a pretty unsophisticated trailing 'impeller', except when we go fast(er) the impeller jumps out of the water. Having a device that simply generates more power at that sort of speed - and faster (and more efficiently) would be ideal, but it (The WattnSea) is currently a bit pricey for us. With the right wind and going in the right direction - we can average 10 knots over 100nm - and we are a not particularly performance orientated 38' cat and I'd expect a 50' cat focused on weight reduction (apart from the batteries :) ) to perform better. I'd exclude a charter cat - and I'm not sure there many charter parties who would have the skills to handle a big cat making 10 knots + - but maybe I'm lacking in charity.

We don't find that our trailing impeller slows us down, I'm sure it does, but when you are making 10 knots - who cares.

Equally maybe 10 amps seems pretty pedestrian - its only money - you just need 2 x water generators (which with a cat you have with the 2 drive pods - to which you can add a WattnSea (and add any solar).

We find making 10 knots, which is not exceptional for big cats (or Tranona's monohull over 70') is 'fast' and you do need to be watching attentively.

The other issue is that if you invest in electric or hybrid power you will very much have a niche vessel - with unique issues and have little background to look to for advice and support. More importantly - the second hand market for such vessels today must be negligible and I don't see (or hear) the market clamouring for that form of technology. I suspect it might be difficult to sell - except at a discount.

Maybe I'm too pessimistic.

But I'd add - there is lots of peripheral interest and developments are coming thick and fast - whatever is available today might look very dated in a few years time.

I can admire those that are willing to stick their neck out - and I'm sure they have done the maths - but I'd wait to see how the concept develops.

Jonathan
 
The price isn't really that big a stepping stone from a diesel and all that entails. The problem as other have said is the power. The 20hp equiv. unit would be able to run for less than an hour at full power from an 800ah bank.

I have a 675ah bank, and that is already nearing 200kg. You'd want probably 4,000ah to give you a days use of the cruise 10.0FP, and half that for the 4.0FP. That's an insane amount of power.

In Ibiza, I met a Swedish guy who had re-powered an old ketch. He's spend tens of thousands on a 48kw battery bank and suitable motor. When I asked about it, he said he regretted it. He'd get about 8 hours range at 2-3knts, obviously less at higher speeds. He joked about being able to see land but when having to motor how agonising the last 10 miles were.

The other option is a generator. This how most trains work. A huge diesel generator powering electric motors. Seems efficient enough for them, but then ticket prices do keep rising. I'm not sure how that would be practical on a boat though.

Not trying to be a 'hater' (as they say), as I'd love to have all electric propulsion.
 
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A mate of mine has a electric setup on his 4.5t cat. (Originally a one-off but now the Broadblue 346). He has twin Azipods run from 48v batteries and charged by a Panda generator. Its very quiet, but he doesn't get very much range on it before the generator kicks in - a matter of minutes.
 
pandroid said:
A mate of mine has a electric setup on his 4.5t cat. (Originally a one-off but now the Broadblue 346). He has twin Azipods run from 48v batteries and charged by a Panda generator. Its very quiet, but he doesn't get very much range on it before the generator kicks in - a matter of minutes.
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Having a generator to produce energy for an electric motor to drive a propeller when the same engine could drive the propeller plus charge batteries and heat water seems a nonsense to me.

Diesel electric (which is what this set up is) is only sensible if the demand for electricity on the vehicle is high as shown in most cruise liners which use it and trains, some of which are dual use - that is run on electricity where there are cables and diesel when they are not present.

A small yacht auxiliary is almost exactly the opposite in that the main requirement is propulsive power and a diesel is the most effective and efficient way of providing this.
 
Battery charging is not really an issue in this case as I have electricity at the mooring and there are quite a few charging points around the broads now. ( I also have sails ! )
Its great to have electric drive as going down the rivers silently is what Broads sailing is about.
 
HunterWanderer said:
Battery charging is not really an issue in this case as I have electricity at the mooring and there are quite a few charging points around the broads now. ( I also have sails ! )
Its great to have electric drive as going down the rivers silently is what Broads sailing is about.
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You have the perfect application for it, and it will be cheaper to run long term than a diesel. I applaud you if you go for it \- as an early aadopter of this kind of technology "off the peg" you will always be paying a premium on us later luddites and nay sayers while at the same time proving the technology for the rest of us. Battery storage and generation will improve to make this kind of set up good for all- eventually - but you sound like you are making a case for it now for your situation. Have you done the maths on payback time with the fuel cost savings you will make or is that info not really available now? The quietness. advantage is not to be underestimated either, but it will surely lead to more "cheating" yachts!
 
HunterWanderer said:
Battery charging is not really an issue in this case as I have electricity at the mooring and there are quite a few charging points around the broads now. ( I also have sails ! )
Its great to have electric drive as going down the rivers silently is what Broads sailing is about.
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I agree - but it is nothing new as electric powered boats have been in use on the Thames for example since the early 1900s. This new pod drive, though is new, although would guess that installation in a wooden boat may be a bit of a challenge.

It is storing and recharging energy that is the major constraint to its adoption in a wider range of boats and types of usage and there is little apart from possibly the battery packs that is transferable from the automotive world and even if that does increase range there is still a need on a cruising boat for electricity for domestic and navigational use which can only come at the expense of range.
 
Tranona said:
would guess that installation in a wooden boat may be a bit of a challenge.
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Not really - from memory the part that goes through the hull fits almost like a seacock skin fitting, then there’s a smaller bolt fore and aft to help resist the torque and a delrin fairing block which you could trim to take up a substantial curve in the hull if there is one. The power and control wiring is a single cable which comes out of the through-hull and goes into a control box you can mount somewhere clear of any bilge water.

I suppose you’d probably want to add some internal framing to take the load rather than putting it all on the planking, but standard wooden-boat stuff and easier than fitting beds for a diesel and drilling the deadwood for a stern tube.

Pete
 
I think that the first requirement is you must want to go electric (or more likely not want fossil fuel) to justify the price premium and lack of range, speed and resale value. For most, electric makes the most sense on the tender (as long as you don’t use it for water sports or exploring) because of using petrol as well as diesel (perhaps a small diesel outboard will kill the electric market). Then it’s just waiting for technology to make the mother ship electric as well, I don’t think electric car technology is the way to go because the constant strain on a boat engine. But Tesla were talking about electric heavy goods trucks, that maybe the future
 
prv said:
Not really - from memory the part that goes through the hull fits almost like a seacock skin fitting, then there’s a smaller bolt fore and aft to help resist the torque and a delrin fairing block which you could trim to take up a substantial curve in the hull if there is one. The power and control wiring is a single cable which comes out of the through-hull and goes into a control box you can mount somewhere clear of any bilge water.

I suppose you’d probably want to add some internal framing to take the load rather than putting it all on the planking, but standard wooden-boat stuff and easier than fitting beds for a diesel and drilling the deadwood for a stern tube.

Pete
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That is fine going through a plank, but would guess the centre line of the boat will have a keel and a keelson that is likely to be quite thick just where you want to install it. Remember the problem from my Seagull days trying to install our prototype saildrive into the type of yachts where there was a demand. It was OK on GRP boats with flattish bottoms, or small launches without keels but problematic with traditional underwater shapes.

An off centre installation might be possible if the keel is not too deep. Would be interesting to see the hull on the OPs boat.
 
Bouba said:
For most, electric makes the most sense on the tender (as long as you don’t use it for water sports or exploring) because of using petrol as well as diesel (perhaps a small diesel outboard will kill the electric market).
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There are, or were, diesel outboards. Though the ones I've seen were not small, 90hp. They are inordinately heavy and expensive (the latter possibly because the market was small). I believe they are heavy because comparing like hp with like hp - diesel is heavier. I guess you could save weight with an alloy block - but that's an idea that never caught on.

They were used by the Oz navy on their RIBs - but I notice they have recently reverted to petrol - and I have not seen the diesels for a couple of years.

Jonathan
 
Neeves said:
There are, or were, diesel outboards. Though the ones I've seen were not small, 90hp. They are inordinately heavy and expensive (the latter possibly because the market was small). I believe they are heavy because comparing like hp with like hp - diesel is heavier. I guess you could save weight with an alloy block - but that's an idea that never caught on.

They were used by the Oz navy on their RIBs - but I notice they have recently reverted to petrol - and I have not seen the diesels for a couple of years.

Jonathan
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Uk forces use diesel outboards because they have a one fuel policy. They are unique designs made by a US company

Yanmar used to make a 28hp diesel outboard for the commercial and fishing market. Very heavy and expensive and killed off in its main Asian market by the development of long tail propulsion using automotive engines. See the james Bond film shot in Thailand for the full visual effects!
 
Tranona said:
Having a generator to produce energy for an electric motor to drive a propeller when the same engine could drive the propeller plus charge batteries and heat water seems a nonsense to me.

Diesel electric (which is what this set up is) is only sensible if the demand for electricity on the vehicle is high as shown in most cruise liners which use it and trains, some of which are dual use - that is run on electricity where there are cables and diesel when they are not present.

A small yacht auxiliary is almost exactly the opposite in that the main requirement is propulsive power and a diesel is the most effective and efficient way of providing this.
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Exactly, what is the point? And the Broads, no charging points there according to a reader who wrote in on exactly this subject.
 
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