Propulsion Power

[Mad Harold]

20 hours ago, Alan de Enfield said:

 

 

Seagull ?

Had an ancient Bond three wheeler, (Villiers 9E) and if memory serves it ran on 16:1.

[Slim]

27 minutes ago, Mad Harold said:

Had an ancient Bond three wheeler, (Villiers 9E) and if memory serves it ran on 16:1.

I've always wanted one of those. I remember one up for sale when I was a schoolboy. £75 if I recall correctly.

[IanD]

16 hours ago, Antrepat said:

Anyone know anything about this one?

 

https://www.voltsport.co.uk/voltsport-marinepropulsionsystems/beltdrivesystem

I talked to Voltsport about these, specifically the "small yacht" version which is a bit beefier.

 

https://www.voltsport.co.uk/voltsport-marinepropulsionsystems/marinebeltdrivesystem

 

They're belt-driven with so they're likely to whine, the aircooled motors are noisy and a bit feeble and can't sustain full power for very long -- and having looked at the motor curves, I'm not even convinced it can achieve this with a 48V input, you need to check details with Voltsport. Motor is rated at 10kW cont/24kW peak at 72V, this should mean 16kW peak at 48V and probably <7kW continuous.

 

If you're happy with all that, they're a relatively cheap solution ?

 

(but maybe not as cheap as you might think when you include everything like throttle/display/mounting feet -- a quote would be interesting...)

Edited March 2, 2021 by IanD

[Antrepat]

3 hours ago, IanD said:

I talked to Voltsport about these, specifically the "small yacht" version which is a bit beefier.

 

https://www.voltsport.co.uk/voltsport-marinepropulsionsystems/marinebeltdrivesystem

 

They're belt-driven with so they're likely to whine, the aircooled motors are noisy and a bit feeble and can't sustain full power for very long -- and having looked at the motor curves, I'm not even convinced it can achieve this with a 48V input, you need to check details with Voltsport. Motor is rated at 10kW cont/24kW peak at 72V, this should mean 16kW peak at 48V and probably <7kW continuous.

 

If you're happy with all that, they're a relatively cheap solution ?

 

(but maybe not as cheap as you might think when you include everything like throttle/display/mounting feet -- a quote would be interesting...)

 

Precisely why I've asked for one

 

Whine I can live with if it's the trade-off for affordability - still less intrusive than thundering diesel, surely.  Sustained navigation at full power, well, if that were necessary then I'd say it means I'd installed insufficient power.  A normal cruising speed shouldn't need full power, and I note that a good estimation ought to consider what's needed to make at least some progress against a river current.  My mooring, after all, is behind a lock that goes straight out onto the River Calder, and the Trent is not that distant (via Keadby, not the terrifying Trent Falls) if one wanted to try a trip to Nottingham or Lincoln.  Referring to all the discussions we had previously, my method of power estimation was based on (some might say brave) canal assumptions.  A river is wider and deeper so things should happen more efficiently, but does that offset the presence of a current so that about the same degree of power is needed for the same speed?

[IanD]

25 minutes ago, Antrepat said:

 

Precisely why I've asked for one

 

Whine I can live with if it's the trade-off for affordability - still less intrusive than thundering diesel, surely.  Sustained navigation at full power, well, if that were necessary then I'd say it means I'd installed insufficient power.  A normal cruising speed shouldn't need full power, and I note that a good estimation ought to consider what's needed to make at least some progress against a river current.  My mooring, after all, is behind a lock that goes straight out onto the River Calder, and the Trent is not that distant (via Keadby, not the terrifying Trent Falls) if one wanted to try a trip to Nottingham or Lincoln.  Referring to all the discussions we had previously, my method of power estimation was based on (some might say brave) canal assumptions.  A river is wider and deeper so things should happen more efficiently, but does that offset the presence of a current so that about the same degree of power is needed for the same speed?

The problem with rivers is if you have to go against the current (upstream), then you need a *lot* more power. I wouldn't like to have less than 15kW/20hp continuous under those circumstances -- I was certainly using this much (from a diesel) on the Trent last year, going upstream after rain. Much less power than that against a reasonable current and you end up needing more overall energy from the batteries not less, because you go too slowly and the trip takes longer.

 

IIRC when I looked at this, the optimum speed through the water (same as in deep still water) was about 1.5x the speed of the current, so if the current is 4kts you want the boat to be able to sustain 6kts in deep still water. Which needs 8x the power (cube law) compared to cruising at 3kts in still water -- I'm sure you can work the numbers out...

[cuthound]

Have you considered nickel iron batteries.?

 

They are cheaper than lion, but more expensive than lead acid and have a proven lifespan of between 20 and 40 years.

 

The main drawbacks are their size (they are not very power dense) and wider voltage fluctuations (easily stabilised by a buck/boost converter).

 

They are often used for standby power, rsilwsy signalling and fork lift truck applications and can be obtained secondhand.

[Antrepat]

4 hours ago, IanD said:

I talked to Voltsport

 

a quote would be interesting...)

 

So, that was fast work, I've had three options back from them.  One is a direct rather than belt drive arrangement.  The motors are Chinese, I think, and are described as PMAC - Ian, that is the type you were recommending, isn't it?  I'll study them and post the results, but all three options are in the £2k realm, including controller, plus £145 for a throttle and £275 for a display.  Gecko want £5k+ for a Lynch Motor Co Marlin 5 (which probably isn't sufficient anyway).  I'd rather send my carefully-hoarded hard-earned Cedric Lynch's way rather than to the lot who seem to have er obtained his IP despite him no longer being associated with them, but that doesn't seem to be an option at the moment (pending Peter's intelligence on the matter).

 

I'm thinking that anything with the required electrical characteristics will actually do as the throttle.  Maybe I should look out for an ex-LU dead man's handle or something and refit it with the right pot, just to be flash.  There is talk of fancy power curves to simulate how diesel engines behave but, erm, why would I want to do that?  It's not a diesel engine.  That strikes me as a bit like becoming vegetarian then eating only fake-meat foods rather than actual vegetables.

 

2 hours ago, IanD said:

The problem with rivers is if you have to go against the current (upstream), then you need a *lot* more power. I wouldn't like to have less than 15kW/20hp continuous under those circumstances -- I was certainly using this much (from a diesel) on the Trent last year, going upstream after rain. Much less power than that against a reasonable current and you end up needing more overall energy from the batteries not less, because you go too slowly and the trip takes longer.

 

IIRC when I looked at this, the optimum speed through the water (same as in deep still water) was about 1.5x the speed of the current, so if the current is 4kts you want the boat to be able to sustain 6kts in deep still water. Which needs 8x the power (cube law) compared to cruising at 3kts in still water -- I'm sure you can work the numbers out...

 

Yes, my model suggests 17.3kW to sustain 6mph (not kt but same ballpark).  15kW would be 75% DoD from a 400Ah 48v battery bank in one hour.  An article I read recently - I didn't bookmark it unfortunately - about a large and lavishly equipped electric canal boat stated that it had a 400Ah battery and that this was a "large" bank.  Hmm.  I know of at least one other (non-speaking) character in this discussion who has a 1kAh bank (LiFePO4, so that's erm never mind, I'll never have that much money).

 

Incidentally, if the suggestion made that a diesel at full power does 30% efficiency at the prop shaft, wouldn't that mean you'd need a 67hp engine to achieve 20hp actual...?

[Antrepat]

1 hour ago, cuthound said:

Have you considered nickel iron batteries.?

 

They are cheaper than lion, but more expensive than lead acid and have a proven lifespan of between 20 and 40 years.

 

The main drawbacks are their size (they are not very power dense) and wider voltage fluctuations (easily stabilised by a buck/boost converter).

 

They are often used for standby power, rsilwsy signalling and fork lift truck applications and can be obtained secondhand.

 

Thanks, no, I've never heard of them but I'll look into it.  My boat is small so enormous weight would be a problem - I've no idea how much the installed diesel weighs but I'm already calculating 500kg for a 400Ah 48v bank, plus maybe 180kg if I had even a modest generator at the bow.  (I couldn't put it at the stern because I imagine it would be impossible to trim the boat without substantial ballast forward, and I suspect it's simply not constructed to be stressed like that.)

[Tony Brooks]

13 minutes ago, Antrepat said:

 

Incidentally, if the suggestion made that a diesel at full power does 30% efficiency at the prop shaft, wouldn't that mean you'd need a 67hp engine to achieve 20hp actual...?

 

I don't think that can be correct in terms of working through HP. A diesel is usually considered about 30% efficient for direct injection in terms of fuel consumed to flywheel HP  but that is not what your calculation implies. It suggests the gearbox absorbs/wastes 70% of the hp at the flywheel. You will lose something through the gearbox but probably only a few % of the available flywheel HP.

 

Your electric motor will be far more efficient so taking Kw in to propshaft the efficiency will be maybe 70% or more (guess from some knowledge) so I think there is a misunderstanding. I have no idea how efficiently the prop turns torque into thrust, but  that will be the same for diesel or electric.

 

 

[Alan de Enfield]

34 minutes ago, Antrepat said:

........  plus maybe 180kg if I had even a modest generator at the bow. 

 

Assumimg you mean a proper marine generator and not a 'builders construction generator' then a 5KVa generator start at 67kg with a big choice under 100kg.

 

The rough size is only 18" x 18" x 18"

 

An 8KVa is only 105kgs, a 10Kva is only 111kg.

 

What generator are you thinking of that weighs 180kg

 

 

Are you looking at a permanent generator installation ?

If so it is much better to try and get it at the stern (nearer the fuel tank) or you are going to have to run fuel from stern to bow to power the "Jenny"

[Antrepat]

3 hours ago, Tony Brooks said:

 

I don't think that can be correct in terms of working through HP. A diesel is usually considered about 30% efficient for direct injection in terms of fuel consumed to flywheel HP  but that is not what your calculation implies. It suggests the gearbox absorbs/wastes 70% of the hp at the flywheel. You will lose something through the gearbox but probably only a few % of the available flywheel HP.

 

Your electric motor will be far more efficient so taking Kw in to propshaft the efficiency will be maybe 70% or more (guess from some knowledge) so I think there is a misunderstanding. I have no idea how efficiently the prop turns torque into thrust, but  that will be the same for diesel or electric.

 

 

 

I was using what Ian said a few days ago:

"Diesel engine at normal canal cruising speed (3kW), <20% efficient (>30% at full power), maybe only 10% when passing moored boats (1kW)

"A good PMAC electric motor plus controller is >90% efficient"

 

...and I took this all to refer to energy input (power out the battery/diesel consumed) vs prop shaft power, which Ian confirmed.

 

My confusion was to read the hp at the wrong end of the engine.  Of course it's at the flywheel - I'm an idiot.  The fact you need to put in a litre of diesel to get the equivalent of 350ml of diesel's energy out is in this context not relevant.  You need to apply 20hp at the prop shaft to make 6kt, and my original model would seem to agree: 

That's mechanical power out, that is, thrust.  Ian (forgive me if it was someone else) suggested typical propeller efficiency as 50-60%, so at 55% 7.3kW would need 13.3kW (17.7hp) at the prop shaft, which is in the same ballpark as Ian's 20hp (phew, although my reckoning is reduced a somewhat for a shorter boat with less skin drag).

 

Unfortunately, 13.3kW would drain a 400Ah battery to 70% DoD in an hour.  I really struggle to reconcile this with the article I read last week about the lavishly-equipped, large electric boat with what was described as a large bank of 400Ah.  Maybe I miscalculated.

 

Addendum: 13.3kW at 48v is 277A, at 72v is 184A.  That's a lot.

Edited March 3, 2021 by Antrepat

[Antrepat]

3 hours ago, Alan de Enfield said:

 

Assumimg you mean a proper marine generator and not a 'builders construction generator' then a 5KVa generator start at 67kg with a big choice under 100kg.

 

The rough size is only 18" x 18" x 18"

 

An 8KVa is only 105kgs, a 10Kva is only 111kg.

 

What generator are you thinking of that weighs 180kg

 

 

Are you looking at a permanent generator installation ?

If so it is much better to try and get it at the stern (nearer the fuel tank) or you are going to have to run fuel from stern to bow to power the "Jenny"

 

I'm glad you pointed this out, Alan, as yes, I had just been looking at "ordinary" generators - not a realm I've got into before so forgive me.  I didn't know that these lightweight, compact ones existed.  The 180kg one was indeed a builders' generator type thing.  I'm guessing you pay more for the compactness and light weight.

 

The limit on generator power is also what the battery can absorb.  I think it's been very thoroughly established that I can't afford LiFePO4, at least not at the same time as doing everything else, so this is going to be evolutionary.  This means probably 0.25C is the limit, and if I haven't completely misunderstood with the notion that a 48v 400Ah battery would be at least adequate, that means a charge rate of 100A maximum, which at that voltage is 4.8kW so 5-6KVA is the maximum.

 

I've observed that 100A chargers are basically non-existent unless you want to buy the mother of all low-frequency transformer ones that are designed for recharging forklifts overnight.  The biggest high-frequency one I've found is 3-phase, 80A at 48v.  When people are charging at above that, for example Lithiums, what do they do?  Rig up several in parallel?  Am I missing something?

 

Re. permanent generator installation: if it weighs 100kg, I don't see there's much choice, is there?  What I was concerned about was putting 500kg of battery + 100kg of generator in the same engine bay as currently occupied by the 30hp (I think) Isuzu diesel.  There are some paving slabs in there for trim purposes but those plus the engine =  600kg?

Edited March 3, 2021 by Antrepat

[Jen-in-Wellies]

6 hours ago, Antrepat said:

Re. permanent generator installation: if it weighs 100kg, I don't see there's much choice, is there?  What I was concerned about was putting 500kg of battery + 100kg of generator in the same engine bay as currently occupied by the 30hp (I think) Isuzu diesel.  There are some paving slabs in there for trim purposes but those plus the engine =  600kg?

Not an Isuzu, but Beta Marine reckon that their 30hp engine plus gearbox weighs 140Kg approximately. If you are getting rid of the starter and 12V leisure batteries and running everything on traction, then reckon around 25Kg for each 110Ahr 12V battery removed. There can be around 200Kg of diesel in the stern tank of a typical narrowboat, but you'll still want this to run the generator. Looks like the much worse energy density of Lead based batteries, compared with Lithium based, is going to need a lot of ballast removed near the stern to give similar trim, then some put back if/when you upgrade to Li.

Jen

[Alan de Enfield]

8 hours ago, Antrepat said:

I'm glad you pointed this out, Alan, as yes, I had just been looking at "ordinary" generators - not a realm I've got into before so forgive me.  I didn't know that these lightweight, compact ones existed.  The 180kg one was indeed a builders' generator type thing.  I'm guessing you pay more for the compactness and light weight.

 

You definitely do not want a 'builders' generator anywhere near your boat.

 

You MUST not install a non-marine generator into the boat, they are not designed for modifications and how would you vent the exhaust overboard without modification ?

(A gas safe registered engineer and plumber, did exactly that and unfortunately killed his wife and child with CO gas).

 

 

Extract from the MAIB report :

 

Arniston’s owner was 39 years old. After leaving school he completed a heating and ventilation apprenticeship, during which he gained City and Guilds qualifications in pipe-fitting and welding. He was also on the ‘Gas Safe Register’4 , which is the official gas registration for the United Kingdom. In 2007, the owner started a business installing and servicing heating and ventilation systems in commercial premises.

 

....................... The two females were taken by air ambulance to Lancaster Royal Infirmary where they were pronounced deceased. A postmortem concluded that the cause of death was carbon monoxide poisoning.

The subsequent MAIB investigation identified that:

• The carbon monoxide poisoning had resulted from the inhalation of fumes emitted from a portable generator installed in the boat’s engine bay.

• The external exhaust system fitted to the portable generator had been modified to incorporate a silencer that had become detached from both the generator and the outlet pipe to the vessel’s side.

• The portable generator’s engine exhaust fumes filled the engine bay and spread through gaps in an internal bulkhead into the aft cabin where the mother and daughter were asleep.

• The portable generator was not intended by its manufacturer to be installed into an enclosed space, nor was it intended to be modified in any way.

• The improvised exhaust system attached to the generator was constructed from materials and using methods that were not appropriate for this application.

• The boat’s occupants were not alerted to the danger because two carbon monoxide sensors fitted to the boat at build were out of date and had been disconnected from the power supply.

 

Secondly, you could not stand the noise and vibration. They are **100x more noisy than a properly installed water cooled marine generator you could not stand the noise for more than a few minutes.

 

** Guesstimate - the noise actually sounds like 1,000,000 x worse.

Edited March 3, 2021 by Alan de Enfield

[IanD]

8 hours ago, Antrepat said:

 

I was using what Ian said a few days ago:

"Diesel engine at normal canal cruising speed (3kW), <20% efficient (>30% at full power), maybe only 10% when passing moored boats (1kW)

"A good PMAC electric motor plus controller is >90% efficient"

 

...and I took this all to refer to energy input (power out the battery/diesel consumed) vs prop shaft power, which Ian confirmed.

 

My confusion was to read the hp at the wrong end of the engine.  Of course it's at the flywheel - I'm an idiot.  The fact you need to put in a litre of diesel to get the equivalent of 350ml of diesel's energy out is in this context not relevant.  You need to apply 20hp at the prop shaft to make 6kt, and my original model would seem to agree: 

That's mechanical power out, that is, thrust.  Ian (forgive me if it was someone else) suggested typical propeller efficiency as 50-60%, so at 55% 7.3kW would need 13.3kW (17.7hp) at the prop shaft, which is in the same ballpark as Ian's 20hp (phew, although my reckoning is reduced a somewhat for a shorter boat with less skin drag).

 

Unfortunately, 13.3kW would drain a 400Ah battery to 70% DoD in an hour.  I really struggle to reconcile this with the article I read last week about the lavishly-equipped, large electric boat with what was described as a large bank of 400Ah.  Maybe I miscalculated.

 

Addendum: 13.3kW at 48v is 277A, at 72v is 184A.  That's a lot.

 

 A couple of comments...

 

Most people considering a boat with a fairly powerful electric motor (e.g. 15kW) will also plan to have a decent-sized generator for several reasons.

1. to provide reasonably quick recharging of a large battery bank (needs a big battery charger too!)

2. to provide extra power under heavy power draw requirements like upstream on a river

3. smaller generators aren't much cheaper than bigger ones, a lot of the costs don't increase with size

4. to power domestic loads (on electric-heavy boats -- because you can...) and still be able to charge batteries if they're flat

 

A typical solution to the charge/inverter/power problem in these boats is something like a Victron Quattro 48/10000, partly because this allows a 230V generator to charge the batteries at 140A -- which in turn leads to the choice of a generator that can supply around 7kW continuously, which given VA/peak ratings means one with a "headline rating" around 10kVA. Most people choose marine 1500rpm generators for lower noise and longer lifetime, even though these are bigger/heavier/more expensive.

 

This means that if you're going upriver starting with full batteries (why wouldn't you?) you would also run the generator, so the net power draw from a 15kW motor drops to 8kW which is >170A at 48V. And yes the motor will draw 300A which is a lot, and the controller has to be able to cope with this -- as do the batteries of the generator isn't running (see below for issue with LA batteries).

 

Now you just have to decide how long you want to do this for, which sets the size of the battery bank. In most cases a couple of hours running upriver is plenty, meaning a 20kWh nominal bank (80% DOD), which is about 400Ah at 48V/51V (LA/LiFePO4). Note that with LA cells the high currents may force a bigger bank to be used since they don't like being discharged quickly, capacity falls off a cliff -- the nominal figure is always at a low rate (e.g. C/10) rate, at C/2 you need a bank typically 50% bigger depending on the exact cells used.

 

If the motor is bigger or the generator is smaller or you want to be able to run for longer (e.g. Ribble Link) a bigger battery bank is needed. With a less powerful motor (e.g. 10kW continuous or lower) you could get away with a smaller one, but would start to be restricted as to how you can use the boat. From the solutions being offered in the market (e.g. Waterworld and others) it seems that 15kW/20hp is becoming the "normal" specification for a typical narrowboat, anything smaller could be fine for many non-river people but may lead to problems if you ever want to sell it on, just like happens with diesel engines today where there's an expected power level for a given length boat.

 

This is all driven by the same reasons as diesel engine size -- for normal cruising the power needed is tiny, you only need a lot in emergencies (stopping quickly, or some other reason you need to get the hell out of Dodge fast) and on rivers. It's why diesels are horribly inefficient because they're running at about a tenth of full power, but the recommended engine sizes are far higher -- typically around 40hp nowadays. Many would say this is overkill partly driven by small props and the need to keep cruising revs/noise/rpm down, which is why half this power (15kW/20hp) is often said to be plenty for an electric/hybrid boat.

 

Compared to all this the required power for normal cruising doesn't have any real influence on motor/battery choice, but a good guesstimate for normal boats on normal UK canals (also back-calculated from diesel rpm/fuel consumption) is 3kW cruising, 1kW passing boats, 0kW in locks -- these are all power at the prop shaft. These figures are higher than those worked out from theoretical hull drag numbers because the drag in a relatively narrow and shallow canal is much higher than in open water.

 

Hope that's helpful... ?

[nb Innisfree]

Battery butties hired for the occasional river/Ribble link trip? Would need to tow via proper linkage instead of strapping to protect electric connection. 

[IanD]

8 minutes ago, nb Innisfree said:

Battery butties hired for the occasional river/Ribble link trip? Would need to tow via proper linkage instead of strapping to protect electric connection. 

Great in theory but impractical -- high-current (and mechanical) connections between butty and boat would need to be standardised as would voltage/current/protection etc, who would own them, how do you stop them piling up at one end...

 

Or were you not being serious? ?

[TheBiscuits]

5 minutes ago, IanD said:

Great in theory but impractical -- high-current (and mechanical) connections between butty and boat would need to be standardised as would voltage/current/protection etc, who would own them, how do you stop them piling up at one end...

 

Or were you not being serious? ?

 

More likely is more use of the tug out of Tarleton than happens now.  If that gets modified or replaced with a "green" one it could tow electric boats most of the way.  

 

The "floating powerstation butty" approach could work though - all it needs to provide is 240V AC at high enough power to charge boats in transit and have sufficient capacity to do the trip more than twice on a charge.  The "up" boat takes it to the moorings on the Ribble Link and the "down" boat brings it back to the boatyard where it can be recharged.  Possibly even add recharge facilities at the Savick Brook end.

 

I don't know who would pay for this though ...

[IanD]

12 minutes ago, TheBiscuits said:

 

More likely is more use of the tug out of Tarleton than happens now.  If that gets modified or replaced with a "green" one it could tow electric boats most of the way.  

 

The "floating powerstation butty" approach could work though - all it needs to provide is 240V AC at high enough power to charge boats in transit and have sufficient capacity to do the trip more than twice on a charge.  The "up" boat takes it to the moorings on the Ribble Link and the "down" boat brings it back to the boatyard where it can be recharged.  Possibly even add recharge facilities at the Savick Brook end.

 

I don't know who would pay for this though ...

Electric boats don't have big enough battery chargers to accept enough 230Vac to charge the batteries and keep up with motor current drain -- and if they have an onboard generator, that's already doing this (e.g. at 7kW, see above).

 

Nobody would pay for it, is the answer -- unless the (not many!) customers paid an absolutely enormous fee to cover the costs (including people), even several hundred quid would probably barely cover it...

[Antrepat]

6 hours ago, Alan de Enfield said:

 

You definitely do not want a 'builders' generator anywhere near your boat.

 

You MUST not install a non-marine generator into the boat, they are not designed for modifications and how would you vent the exhaust overboard without modification ?

(A gas safe registered engineer and plumber, did exactly that and unfortunately killed his wife and child with CO gas).

 

 

Extract from the MAIB report :

 

Arniston’s owner was 39 years old. After leaving school he completed a heating and ventilation apprenticeship, during which he gained City and Guilds qualifications in pipe-fitting and welding. He was also on the ‘Gas Safe Register’4 , which is the official gas registration for the United Kingdom. In 2007, the owner started a business installing and servicing heating and ventilation systems in commercial premises.

 

....................... The two females were taken by air ambulance to Lancaster Royal Infirmary where they were pronounced deceased. A postmortem concluded that the cause of death was carbon monoxide poisoning.

The subsequent MAIB investigation identified that:

• The carbon monoxide poisoning had resulted from the inhalation of fumes emitted from a portable generator installed in the boat’s engine bay.

• The external exhaust system fitted to the portable generator had been modified to incorporate a silencer that had become detached from both the generator and the outlet pipe to the vessel’s side.

• The portable generator’s engine exhaust fumes filled the engine bay and spread through gaps in an internal bulkhead into the aft cabin where the mother and daughter were asleep.

• The portable generator was not intended by its manufacturer to be installed into an enclosed space, nor was it intended to be modified in any way.

• The improvised exhaust system attached to the generator was constructed from materials and using methods that were not appropriate for this application.

• The boat’s occupants were not alerted to the danger because two carbon monoxide sensors fitted to the boat at build were out of date and had been disconnected from the power supply.

 

Secondly, you could not stand the noise and vibration. They are **100x more noisy than a properly installed water cooled marine generator you could not stand the noise for more than a few minutes.

 

** Guesstimate - the noise actually sounds like 1,000,000 x worse.

 

100% convinced, thank you for this.

[Antrepat]

 

4 hours ago, nb Innisfree said:

Battery butties hired for the occasional river/Ribble link trip? Would need to tow via proper linkage instead of strapping to protect electric connection. 

 

4 hours ago, IanD said:

Great in theory but impractical -- high-current (and mechanical) connections between butty and boat would need to be standardised as would voltage/current/protection etc, who would own them, how do you stop them piling up at one end...

 

Or were you not being serious? ?

 

Funnily enough, I was just reading last night about the electric tug that used to operate through Harecastle tunnel.  I've read in several places that it was powered from overhead lines, but this book said that, upon introduction in 1914, it had an "accumulator butty" with a battery of 115 chloride cells which took a week to charge.  During charging, I suppose it was simply back to legging through, unless there was more than one tug or at least more than one accumulator butty.  Anyway, the wires were installed in 1931 - apparently the sparking could get quite exciting.  This lasted until 1953 when the tug was discontinued and fans were installed to improve ventilation enough to allow self-propelled boats to navigate through.  Interestingly, the tug had two 15hp motors with no propellor losses because it hauled itself along a cable picked up from the bed of the canal, with up to 30 boats towed behind it.  Adds a new perspective to our discussions about power, eh?

 

(Narrow Boats by Tom Chaplin, 1989 ed., ISBN 0-905483-71-5, pp. 34-5.)

Edited March 3, 2021 by Antrepat

[IanD]

1 minute ago, Antrepat said:

 

 

 

Funnily enough, I was just reading last night about the electric tug that used to operate through Harecastle tunnel.  I've read in several places that it was powered from overhead lines, but this book said that, upon introduction in 1914, it had an "accumulator butty" with a battery of 115 chloride cells which took a week to charge.  During charging, I suppose it was simply back to legging through, unless there was more than one tug or at least more than one accumulator butty.  Anyway, the wires were installed in 1931 - apparently the sparking could get quite exciting.  This lasted until 1953 when the tug was discontinued and fans were installed to improve ventilation enough to allow self-propelled boats to navigate through.  Interestingly, the tug had two 15hp motors with no propellor losses because it hauled itself along a cable picked up from the bed of the canal, with up to 30 boats towed behind it.  Adds a new perspective to our discussions about power, eh?

 

(Narrow Boats by Tom Chaplin, 1989 ed., ISBN 0-905483-71-5, pp. 34-5.)

But don't forget that it towed several hundred boats a day through the tunnel (anyone know the actual number?) so the cost was spread very thinly. That's probably far more boats in a day than the Ribble Link sees in an entire year...

[Antrepat]

Just now, IanD said:

But don't forget that it towed several hundred boats a day through the tunnel (anyone know the actual number?) so the cost was spread very thinly. That's probably far more boats in a day than the Ribble Link sees in an entire year...

No doubt!  I was just inserting some historical trivia...

 

Let's guess at an hour to get through the tunnel and two hours to disperse the train and assemble the next.  I reckon they could do two or three runs a day, maximum, of 30 boats, so that'd be an average of 45 boats a day each way.

[IanD]

1 minute ago, Antrepat said:

No doubt!  I was just inserting some historical trivia...

 

Let's guess at an hour to get through the tunnel and two hours to disperse the train and assemble the next.  I reckon they could do two or three runs a day, maximum, of 30 boats, so that'd be an average of 45 boats a day each way.

I think if you look at the history of the tunnel it was a much slicker operation than that, otherwise they'd have carried on legging or using steam tugs...

[TheBiscuits]

1 minute ago, Antrepat said:

No doubt!  I was just inserting some historical trivia...

 

Let's guess at an hour to get through the tunnel and two hours to disperse the train and assemble the next.  I reckon they could do two or three runs a day, maximum, of 30 boats, so that'd be an average of 45 boats a day each way.

 

 

Surely you'd assemble the next train of boats while the current one is in the tunnel, then just connect the tug and set off again.

 

The tug doesn't need to wait while the towed boats sort themselves out after leaving the tunnel, neither does it need to wait while the next train is being assembled.