Swapping from red diesel to HVO fuel

[ditchcrawler]

This boat is powered by two electric pods, one at the bow and one at the stern both steerable through about 340 deg the stern one being larger

[gary955]

To bring the thread back on topic! Crown oil told me today that they will no longer deliver from a tanker to a boat. I wanted 1500lts of HVO and had an agreement from a marina for the delivery to be made at their fuel pontoon, directly from a tanker. If anyone knows of an alternative supplier, I'd be grateful.

[dmr]

54 minutes ago, gary955 said:

To bring the thread back on topic! Crown oil told me today that they will no longer deliver from a tanker to a boat. I wanted 1500lts of HVO and had an agreement from a marina for the delivery to be made at their fuel pontoon, directly from a tanker. If anyone knows of an alternative supplier, I'd be grateful.

Ive been using New Era fuels who I think work out a fair bit cheaper than Crown, though its hard to do a proper comparison when prices are so volatile. I have had 200litre drums delivered to a land address, not directly to a boat.  I suspect that with all the confusion about duty on domestic and propulsion, and restrictions on HVO, that the suppliers have decided that working with boats is just too difficult. I assume they are just not geared up for collecting duty on 60:40 splits etc etc or deciding which boats might be commercial. 

[dmr]

3 hours ago, IanD said:

 

Agree with your first two comments, it annoys me too... 😉

 

(but 30hp at 500rpm needs a *massive* prop (30" x 28"?) -- lovely if it will fit on your boat, and you don't mind dredging the canals for everyone else...)

 

48V is a bit of a pain when you get above 15kW, but mainly because of the controllers, the batteries and (short!) cables are happy enough. The workable next solution up is a 30kW/40hp 6-phase motor using 2 controllers, which is exactly what Engiro do -- each of the controllers (and cabling) is identical to the 15kW one, LFP batteries are perfectly happy providing huge currents. Anything above this gets difficult, but isn't needed on the canal system even if you venture out onto rivers.

 

Nothing wrong with you liking big slow old diesels, I like the sound too (though not as much as a Bolinder) but preferably on somebody else's boat. *Especially* a Bolinder... 😉

 

A much smaller prop than than that. We produce about 35 horse at about 1200rpm so thats 600rpm prop speed (2:1 reduction) and a 21" by 20" prop is about right. A slighty deeper modern boat can manage a 21" prop, you don't need a 3' 6" working boat.

 

I accept that two 48v motors and two separate controllers might be a way forward, and offer some redundacytoo  which is always a good thing, but will still be taking 480 amps from the battteries. Apart from potential losses I fear that big amps and slightly poor connections are a recipe for fires.  There is a good reason why the national grid does not run at 48volts  😀.

 

As a complete aside I am contemplating a 48 volt lithium bank plus 48volt alternator to replace the Travelpower whilst also providing more storage (though if I do this I will retain the 12 volt lead acid bank), so I am not opposed to new fangled technology..

[Bargebuilder]

11 minutes ago, dmr said:

I suspect that with all the confusion about duty on domestic and propulsion, and restrictions on HVO, that the suppliers have decided that working with boats is just too difficult.

I forget the suppliers name now, but I was refused a delivery onto my barge, the stated reason being the risk of pollution and insurance.

I fear that this might be a trend.

[dmr]

3 minutes ago, Bargebuilder said:

I forget the suppliers name now, but I was refused a delivery onto my barge, the stated reason being the risk of pollution and insurance.

I fear that this might be a trend.

 

I think that is a good argument. There are likely all sorts of "fuel supply near water" regulations that are outside the experience of the fuel suppliers. I believe another issue is that the tanker nozzle is much too big to fit a standard boat diesel filler.  In our case filling the tank without blowback can be a slow and tedious job and a diesel tanker likely does not want to take 40minutes trickling fuel into a badly behaved boat.

I suspect just delivering a 200litre drum to the canalside would break a lot of regulations.

[peterboat]

18 hours ago, IanD said:

Power and speed and toughness and "coping all day with the tidal Thames" are nothing to do with efficiency, you're just trying to distract again.

 

You claimed that the Lynch DC motor and controller are as efficient as a PMAC one but have provided no data to back this up -- and it's not the first (or seond, or third, or...) time you've done this sort of thing, claiming something that doesn't stack up and then trying to wriggle out of it when challenged... 😉

 

 

No I am saying that 98% of the time the difference between the two setups isnt worth bothering about especially given the high cost of yours against mine! My setup is affordable to lots of boaters, yours is affordable to just a few in comparison. James has the 155R on the tidal Thames with no issues at all, like I have no issues on rivers with currents.

Towpath talk is on about electric boats this month its worth a read it seems that 72 volts systems like mine are ok, its considered safe and 50 volts and below ultra safe. However a warning was given about 48 volt systems that then use a inverter to up to mains voltages interesting stuff and well worth the read

[Bargebuilder]

2 minutes ago, dmr said:

 

I think that is a good argument. There are likely all sorts of "fuel supply near water" regulations that are outside the experience of the fuel suppliers. I believe another issue is that the tanker nozzle is much too big to fit a standard boat diesel filler.  In our case filling the tank without blowback can be a slow and tedious job and a diesel tanker likely does not want to take 40minutes trickling fuel into a badly behaved boat.

I suspect just delivering a 200litre drum to the canalside would break a lot of regulations.

If you've had a recent delivery of a 200l drum, may I ask how much does such cost and is there a minimum delivery? Do the drivers have any special requirements for storage of the drums?

 

You are so right about filler size hole on boats and speed of filling. On one occasion on our barge, the over enthusiastic delivery driver with his finger firmly squeezed on the trigger, ended up with a diesel fountain and in need of a change of overalls! Fortunately, the barge was in the yard at the time and not in the water.

[Alan de Enfield]

16 minutes ago, dmr said:

In our case filling the tank without blowback can be a slow and tedious job and a diesel tanker

 

We have had tankers come down to harbours if the harbour / sailing club have insufficient supplies for our needs.

 

Most tankes have a variety of nozzle sizes in a rack in the 'tool box' and a much smaller one does help reduce the 'blow-back of froth if it gets too full, and slows down the dispense.

Its certainly something we would avoid if there was a choice.

[IanD]

13 minutes ago, dmr said:

 

A much smaller prop than than that. We produce about 35 horse at about 1200rpm so thats 600rpm prop speed (2:1 reduction) and a 21" by 20" prop is about right. A slighty deeper modern boat can manage a 21" prop, you don't need a 3' 6" working boat.

 

I accept that two 48v motors and two separate controllers might be a way forward, and offer some redundacytoo  which is always a good thing, but will still be taking 480 amps from the battteries. Apart from potential losses I fear that big amps and slightly poor connections are a recipe for fires.  There is a good reason why the national grid does not run at 48volts  😀.

 

As a complete aside I am contemplating a 48 volt lithium bank plus 48volt alternator to replace the Travelpower whilst also providing more storage (though if I do this I will retain the 12 volt lead acid bank), so I am not opposed to new fangled technology..

 

Going by the Vicprop calculator -- which has proved pretty accurate compared to what various diesel manufacturers recommend, and actual measurements on various electric boats -- 35hp at 1200rpm with a 2:1 gearbox needs a 27.6" x 22.8" prop, which is *way* bigger than yours. A 21" x 20" prop will only absorb about 15hp at 1200rpm engine speed, which suggests you're heavily underpropped -- the boat might well pootle along nicely, but at maximum rpm you're only using about half the engine power.

 

It's not two 48V motors and two controllers (though this is obviously possible), it's one 6-phase 25kW@48V motor driven by 2 3-phase 12.5kW controllers, each wired to the 48V battery and drawing 260A.

 

https://www.voltsport.co.uk/Engiro-205W_12202?manufacturer_id=23&page=4

 

The currents in the wiring are a bit lower than the 15kW 3-phase motor with one controller, but there are twice as many cables. The LFP batteries are perfectly happy to be discharged at 1C which is 700A. Really, it's not a problem at these current/power levels 48V is fine. At EV/big boat power levels, it makes much more sense to go straight to 400V (where again there's lots of kit available) to get much lower currents and thinner cables, not 72V or 96V. There are plenty of systems out there running at these currents, as you say you do need good connections but then the terminals are massive and rated to far higher currents than actually used.

 

IF you're looking at a 48V alternator, be aware that these are *very* expensive (well over a grand each) and also need a proper external controller like the Wakespeed which is also expensive (about £600?). They also don't produce much output at low rpm, so you have to run the engine faster than normal to get the quoted output current. When I looked at this two 24V 100A alternators in series were a lot cheaper and produced more current at lower rpm.

[dmr]

6 minutes ago, Bargebuilder said:

If you've had a recent delivery of a 200l drum, may I ask how much does such cost and is there a minimum delivery? Do the drivers have any special requirements for storage of the drums?

 

You are so right about filler size hole on boats and speed of filling. On one occasion on our barge, the over enthusiastic delivery driver with his finger firmly squeezed on the trigger, ended up with a diesel fountain and in need of a change of overalls! Fortunately, the barge was in the yard at the time and not in the water.

 

Buying HVO in 200litre drums is an expensive way to do it but I have no other option.There is no minimum order (well 200litres 😀)  Delivery is "free" but the more drums you have the cheaper it becomes so I assume the hefty  deivery charge is secretly added to the fuel price. I don't think there are any requirements from the driver as to how the fuel is stored, I was not asked about bunds etc. I also think (not sure) that it gets more difficult if more than 400 litres is delivered. I can't be sure of any of this because despite my requests the fuel arrived on a truck that was too big for our road so we had to drive out in a smaller truck and transfer the drums at the side of the road. I think this probably contravened some regulations.

[IanD]

33 minutes ago, peterboat said:

No I am saying that 98% of the time the difference between the two setups isnt worth bothering about especially given the high cost of yours against mine! My setup is affordable to lots of boaters, yours is affordable to just a few in comparison. James has the 155R on the tidal Thames with no issues at all, like I have no issues on rivers with currents.

Towpath talk is on about electric boats this month its worth a read it seems that 72 volts systems like mine are ok, its considered safe and 50 volts and below ultra safe. However a warning was given about 48 volt systems that then use a inverter to up to mains voltages interesting stuff and well worth the read

 

I agree that if you're not using full power (or close to it) for any length of time there's not that much difference, but for many people not being able to rely on full power for a couple of hours upstream is a big downside, and one of the big objections to electric boats -- have you ever done this on yours? It's not whether you've ever had a problem on a river, have you ever hammered upstream at full power for 2 hours or more -- if not, you don't know whether your setup can cope with this not. Same applies to your mates on the Thames...

 

You also seem to have ignored the actual prices I gave -- based on real quotes, not handwaving -- which showed that a comparable Lynch electric drive system was not any cheaper...

 

(I'm ignoring the batteries/inverter/generator because that's not what we're talking about here, you can do those cheap (second-hand) or expensive (new)...)

 

Regardless of what you consider safe, the regulations are very clear -- only systems at 60V maximum DC voltage or less qualify as ELV and escape the tighter safety rules, which means 48V nominal (maybe 58V max when fully charged). Your opinions or those of towpath talk or anyone else don't override the regulations. It's why not only all the Victron inverters but also every mild hybrid car uses 48V, to avoid the cost and hassle of higher voltages. EVs have to go higher to cope with the power levels, they go straight to 400V DC because there's no extra cost compared to 72V, but currents are more than 5x smaller and wiring (and other components like controllers) are much smaller and cheaper.

 

For inverters that step up to mains voltage, the same rules apply as to any mains circuits regarding testing, qualification, insulation, touchability, installation and so on -- for example it must be impossible for probes (e.g. fingers) or a certain size to touch any live component, and all insulation must be qualified as safe. If this is not done then the supplier could have major liability issues should anything go wrong -- you don't care because it's your boat, but then you wouldn't sue yourself if you got electrocuted because of not following the rules.

 

This is not just some theoretical legal waffling, it's the law. You can ignore it if you want, but few commercial suppliers will for a drive system they supply -- sure they'll sell you the bits with a warning label attached, if you want to kill yourself by putting it together badly it's not their problem... 😉

Edited July 28, 2022 by IanD

[peterboat]

1 minute ago, IanD said:

 

I agree that if you're not using full power (or close to it) for any length of time there's not that much difference, but for many people not being able to rely on full power for a couple of hours upstream is a big downside -- have you ever done this on yours? It's not whether you've ever had a problem, have you ever hammered upstream at full power for 2 hours -- if not, you don't know whether your setup can cope with this not.

 

You also seem to have ignored the actual prices I gave -- based on real quotes, not handwaving -- which showed that a comparable Lynch electric system was not any cheaper...

 

Regardless of what you consider safe, the regulations are very clear -- only systems at 60V maximum DC voltage or less qualify as ELV and escape the tighter safety rules, which means 48V nominal (maybe 56V max when fully charged). Your opinions or those of towpath talk or anyone else don't override the regulations. It's why not only all the Victron inverters but also every mild hybrid car uses 48V, to avoid the cost and hassle of higher voltages. EVs have to go higher to cope with the power levels, they go straight to 400V DC because there's no extra cost compared to 72V, but currents are more than 5x smaller and wiring (and other components like controllers) are much smaller and cheaper.

 

For inverters that step up to mains voltage, the same rules apply as to any mains circuits regarding testing, qualification, insulation, touchability, installation and so on -- for example it must be impossible for probes (e.g. fingers) or a certain size to touch any live component, and all insulation must be qualified as safe. If this is not done then the supplier could have major liability issues should anything go wrong -- you don't care because it's your boat, but then you wouldn't sue yourself if you got electrocuted because of not following the rules.

 

This is not just some theoretical legal waffling, it's the law. You can ignore it if you want, but few commercial suppliers will for a drive system they supply -- sure they'll sell you the bits with a warning label attached, if you want to kill yourself by putting it together badly it's not their problem... 😉

Read the article Ian, its written by RCR, BSS  and CRT as well as Lynch. The Governments low voltage directive says 72 volts is classed as safe and 50volts ultra safe

[dmr]

2 minutes ago, IanD said:

 

Going by the Vicprop calculator -- which has proved pretty accurate compared to what various diesel manufacturers recommend, and actual measurements on various electric boats -- 35hp at 1200rpm with a 2:1 gearbox needs a 27.6" x 22.8" prop, which is *way* bigger than yours. A 21" x 20" prop will only absorb about 15hp at 1200rpm engine speed, which suggests you're heavily underpropped -- the boat might well pootle along nicely, but at maximum rpm you're only using about half the engine power.

 

It's not two 48V motors and two controllers (though this is obviously possible), it's one 6-phase 25kW@48V motor driven by 2 3-phase 12.5kW controllers, each wired to the 48V battery and drawing 260A.

 

https://www.voltsport.co.uk/Engiro-205W_12202?manufacturer_id=23&page=4

 

The currents in the wiring are a bit lower than the 15kW 3-phase motor with one controller, but there are twice as many cables. The LFP batteries are perfectly happy to be discharged at 1C which is 700A. Really, it's not a problem at these current/power levels 48V is fine. At EV/big boat power levels, it makes much more sense to go straight to 400V (where again there's lots of kit available) to get much lower currents and thinner cables, not 72V or 96V. There are plenty of systems out there running at these currents, as you say you do need good connections but then the terminals are massive and rated to far higher currents than actually used.

 

IF you're looking at a 48V alternator, be aware that these are *very* expensive (well over a grand each) and also need a proper external controller like the Wakespeed which is also expensive (about £600?). They also don't produce much output at low rpm, so you have to run the engine faster than normal to get the quoted output current. When I looked at this two 24V 100A alternators in series were a lot cheaper and produced more current at lower rpm.

 

We have the Beta JD3 Its no longer on the Beta website but they specified a 20" x 20" prop so we are just a fraction over-propped if anything. Going flat out we are just getting onto black smoke which also confirms that the prop is about correct.  However I am a bit confused about all this as if you do a forum search it appears that some vintage engines with a similar rating do run much bigger props.

Its possible that our very top speed is actually 1300 or even 1400 which could make difference. I will try to check this next time we are on a river.

 

The cost of a 48 volt alternator is one thing stopping me doing a 48volt system. The Balmar is the most common and it is expendive and it does need an expensive external controller. Low output at low speed is also a concern. I would like an "almost drop in replacement" for the Travelpower so two series alternators are not an option. Also intuitively I really don't like series alternators.

[IanD]

7 minutes ago, dmr said:

 

We have the Beta JD3 Its no longer on the Beta website but they specified a 20" x 20" prop so we are just a fraction over-propped if anything. Going flat out we are just getting onto black smoke which also confirms that the prop is about correct.  However I am a bit confused about all this as if you do a forum search it appears that some vintage engines with a similar rating do run much bigger props.

Its possible that our very top speed is actually 1300 or even 1400 which could make difference. I will try to check this next time we are on a river.

 

The cost of a 48 volt alternator is one thing stopping me doing a 48volt system. The Balmar is the most common and it is expendive and it does need an expensive external controller. Low output at low speed is also a concern. I would like an "almost drop in replacement" for the Travelpower so two series alternators are not an option. Also intuitively I really don't like series alternators.

 

Beta JD3 is 30bhp at 1200rpm according to the data sheet. It will go up to 1400rpm at which it's 35hp.

 

I talked to Beta about fitting the Balmar 48V 100A alternator (I assume this is the one you mean?) to the Beta 43 and their comment was that due to the heavy loading on the pulleys and bearings (even more than the Travelpower) they would have to try one out (with the mounting hardware) and make sure there were no problems before agreeing to support it, IIRC they would charge something like £500 for doing this. Since they don't do the JD3 any more I suspect they'd say "you're on your own mate, don't come back and complain to us if it kills your engine"...

Edited July 28, 2022 by IanD

[dmr]

8 minutes ago, IanD said:

 

Beta JD3 is 30bhp at 1200rpm according to the data sheet. It will go up to 1400rpm at which it's 35hp.

 

I talked to Beta about fitting the Balmar 48V 100A alternator (I assume this is the one you mean?) to the Beta 43 and their comment was that due to the heavy loading on the pulleys and bearings (even more than the Travelpower) they would have to try one out (with the mounting hardware) and make sure there were no problems before agreeing to support it, IIRC they would charge something like £500 for doing this. Since they don't do the JD3 any more I suspect they'd say "you're on your own mate, don't come back and complain to us if it kills your engine"...

 

There are numerous variations on the John Deere 3029 with slightly different torque curves and for various reasons we currently have a slightly different one to that which Beta use.  The top speed is actually pretty arbitrary depending only upon the prop size, the setting of the top speed adjustment screw, and how brave you are 😀.

Its a tough engine and in a different league to the Beta 43 so I would not be too concerned about loading up the front end and would not expect any help from Beta,.

I think Balmar do a 60amp alternator version??? and I would probably use this to keep the loading similar to the Travelpower.

 

Have not been on a river since we switched to HVO so I will be very interested to see how the engines performs when worked really hard.

[IanD]

1 minute ago, dmr said:

 

There are numerous variations on the John Deere 3029 with slightly different torque curves and for various reasons we currently have a slightly different one to that which Beta use.  The top speed is actually pretty arbitrary depending only upon the prop size, the setting of the top speed adjustment screw, and how brave you are 😀.

Its a tough engine and in a different league to the Beta 43 so I would not be too concerned about loading up the front end and would not expect any help from Beta,.

I think Balmar do a 60amp alternator version??? and I would probably use this to keep the loading similar to the Travelpower.

 

Have not been on a river since we switched to HVO so I will be very interested to see how the engines performs when worked really hard.

The 60A one is probably a better choice, not just for loading but IIRC it produces more current at low revs than the 100A one, which is what you want on the canals. You'll probably need some custom brackets though, I don't think it's a drop-in replacement for the Travelpower.

[MtB]

1 hour ago, Bargebuilder said:

You are so right about filler size hole on boats and speed of filling. On one occasion on our barge, the over enthusiastic delivery driver with his finger firmly squeezed on the trigger, ended up with a diesel fountain and in need of a change of overalls! Fortunately, the barge was in the yard at the time and not in the water.

 

 

I wouldn't mind betting this is the beginning and the end of why they are stopping supplying from tankers direct to boat. One soaking in diesel fron the blow-back fountain effect and the driver needs/is probably entitled/required to take a shower and have a change of clothes or take the rest of the day off. A massive upheaval and disruption for delivery companies working on fag-paper thin profit margins, wiping out possibly days of profit wrung from that particular lorry. Never mind the fines they might be in line for, for the polution.

 

 

 

 

[gary955]

Can we have a mod steer this thread back to HVO? One of the most frustrating features of this forum is topic wander. Only about half of the replies to a thread about HVO are actually about HVO. It's a very busy forum if your interest is wandering off the subject, start a new thread! you'll still have plenty of input.

[dmr]

3 minutes ago, IanD said:

The 60A one is probably a better choice, not just for loading but IIRC it produces more current at low revs than the 100A one, which is what you want on the canals. You'll probably need some custom brackets though, I don't think it's a drop-in replacement for the Travelpower.

 

I think it just might be, but luckily I have access to a workshop with facilities for drilling holes in thick steel, and welding it 😀.

I reckon about 6kW-hour of Lithiums at 48 volts would be really good and mean that we could go several days without running the engine, including running the washing machine a couple of times. It will be £6000-£7000 which is a bit scary. The bit I have not worked out is how to do hot water for a shower. Currently we need to run the engine at least every third day.

[dmr]

1 minute ago, gary955 said:

Can we have a mod steer this thread back to HVO? One of the most frustrating features of this forum is topic wander. Only about half of the replies to a thread about HVO are actually about HVO. It's a very busy forum if your interest is wandering off the subject, start a new thread! you'll still have plenty of input.

Mods can't do that, and this is the way that this forum goes. This thread is doing a lot better than most and HVO and electric drive are both related to solving the net zero problem. However It would be better if the electric stuff could go into its own thread because its a huge and important subject.

[cuthound]

9 hours ago, IanD said:

I agree 100% with your first few points, which is why series hybrids are increasing in popularity -- at least, among those fortunate enough to be able to afford them... 😉

 

All equipment for yachts tends to be expensive for several reasons; one is the amount of work needed to get it to pass various worldwide qualification standards, but a simpler reason (warning -- generalisation follows!) is that yacht owners see their hobby as expensive and are both richer and willing to pay more for stuff than penny-pinching narrowboaters 🙂

There's also the general fact that new technology made in small volumes is always more expensive than old technology made in big volumes, and even on the yacht market pod propulsion is a tiny part of the market -- and electric pod propulsion an even tinier part of an even smaller market. I looked at all this when I was investigating hybrid propulsion systems, and a 15kW Azipod or similar (plus controller/display etc.) was *horrendously* expensive, getting on for £20k IIRC just for the drive system.

 

In comparison (all 48V systems capable of 15kW continuous output) the Bell Marine motor plus all the bits needed to make it work was about £12k, the Lynch twin-motor one was (surprisingly!) something over £8k, the Waterworld one was £7.5k, and the Voltsport one was £4k -- but this was just for the basic motor/controller components, they didn't do the "kit" then and I guess this would be significantly more expensive -- but probably still cheaper than the others, as well as being one of the best-performing solutions. Which was why I was going to got that way until I decided to let Finesse deal with it all -- and their system is based on similar components...

 

Which kind of shoots Peter's claim that Lynch are cheap in the foot -- maybe they are if you just buy a single bare motor (which probably can't sustain the power needed, at least not at 48V) and engineer all the mounting parts and pulleys/belts yourself, and put your own control system together, but I don't think most people can (or want to) do this, they want something which can be installed with a similar level of difficulty to a diesel engine/gearbox. That's the apples-to-apples comparison with the prices above, but note that this is just the cost for the drive system, it doesn't include the other more expensive bits like batteries, inverter and generator which is what really pushes the total cost up.

 

I'm sure Peter will come back and say it ain't so and his system works for him and cost less than a box of cornflakes, but I know that there are a couple of big gotchas with his solution. The first is that he runs at 72V, which no drive supplier is going to do because this is above the low-voltage range and puts a huge extra safety burden on the design and manufacture -- which Peter can ignore, because if he electrocutes himself (however unlikely it is) it's his problem. But if this happens to any boater from a commercially supplied drive system which is not properly safety qualified (expensive) they can sue the socks off them, which is why almost all suppliers won't take this risk (or go through the safety certification hassle) and they're all 48V -- the same applies to the inverter/chargers and batteries.

 

The second is that as far as I can tell none of the single Lynch motors can sustain 15kW for at least 2 hours -- preferably more -- which is becoming accepted as the industry norm for a "go-anywhere" narrowboat, meaning one that can pass the Ribble Link or go up rivers like the Trent against strong currents -- and no amount of claiming "my mate's boat is fine on the Thames" changes this, pootling up the Thames is *far* less stressful. The last thing you want to happen is for the motor or controller to overheat after maybe half an hour going upstream and either reduce power or even worse cut out, because by then you're committed. Hope you have a good anchor and know how to use it... 😉

 

This is why the 48V Lynch boat systems that I posted use two motors -- and two controllers -- to be able to deliver these levels of power continuously. A single motor can easily deliver short-term power well above this which is fine for cars and bikes, but not for boats. The same is actually true for quite a lot of the cheaper "electric boat" solutions on the market using cheap belt-driven motors (e.g. Motenergy) sourced from China, the peak power is high but the continuous power is not. But they *are* cheap -- in fact cheaper than UK-built Lynch motors, which is probably why Hybrid Marine now use them (water-cooled) instead of the Lynch motors they used to use in their parallel hybrids...

 

I used to design 400 volt DC systems. To ensure they complied with the safety regulstions, you put contactors into the battery interconnects to seperate the battery into 50 volt sections. These were interlocked into the battery room door, so that you couldn't gain entry without breaking the battery into low voltage sections.

 

I'm sure it would be much easier to achieve with a 72 volt battery in a box.

Edited July 28, 2022 by cuthound
Phat phingers

[Bargebuilder]

12 minutes ago, MtB said:

Never mind the fines they might be in line for, for the polution.

From my conversation, the supplier was much more concerned about the environment agency and the huge scale of possible fines, plus, their inability to justify the insurance premium for the additional cover needed to deliver to boats, that being such a tiny market for them.

 

We used to prefer buying from the tanker because of the muck and water that can form part of the fuel supplied from marina tanks, fuel that can be stale after having lingered in these tanks for many months.

[cuthound]

8 hours ago, MtB said:

Like this perhaps:

 

 

 

 

That is similar, but smaller than a pair of 1600 amp DC motor generator sets that I had to maintain when I first started work.

 

They were controlled by a black coloured switchboard with edge sprung knife switches and a Brown Boveri regulator. God knows how old they were but they were lovely machines.

[MtB]

39 minutes ago, gary955 said:

Can we have a mod steer this thread back to HVO? One of the most frustrating features of this forum is topic wander. Only about half of the replies to a thread about HVO are actually about HVO. It's a very busy forum if your interest is wandering off the subject, start a new thread! you'll still have plenty of input.

 

 

As dave says, this is how this forum is run. Others are stricter about staying on topic. 

 

But there's no point asking in the thread. If you want something done about it you'll have to report the posts you think break forum rules. I doubt you'll get much from Team Mod beyond the same as I just said and a polite refusal though.