My big boat convered to electric drive

[peterboat]

4 hours ago, ditchcrawler said:

Its good to see a posing with all the warts and all. unlike some that say I have a marvellous system and then nothing.

You are right Brian this has been a bit of a mess around to say the least, cost wise its not been bad, but I am happy with the end result. If I was doing a narrowboat it would be easier apart from the solar, I suspect it would a great deal less power than I need to achieve 3 MPH, which would mean a lower voltage motor could be used etc etc

[Ray T]

https://cruisingthecut.co.uk/2019/04/15/vlog-169-hire-purpose/

 

Gets to the point 3 minutes in.

 

 

Edited April 16, 2019 by Ray T

[peterboat]

8 minutes ago, Ray T said:

https://cruisingthecut.co.uk/2019/04/15/vlog-169-hire-purpose/

I have 3.6 kw of solar on a sunny day it keeps up with demand easily, also my LifePo4 batteries will take all the charge thrown at them unlike the full traction batteries in that boat, its really apples and oranges the difference between mine and theirs

[hawkesmith]

Congratulations on the build. I am so envious!

[peterboat]

1 hour ago, hawkesmith said:

Congratulations on the build. I am so envious!

Cheers second time around was no easier than the first!!

[LadyG]

17 hours ago, Ray T said:

https://cruisingthecut.co.uk/2019/04/15/vlog-169-hire-purpose/

 

Gets to the point 3 minutes in.

 

 

I can envisage some sort of Electric point infrastructure, a bit like Boris Bikes in London, it could only work for hybrids and in popular locations., and would seem to be very prone to chaos.

 

Edited April 17, 2019 by LadyG

[Dr Bob]

3 hours ago, LadyG said:

I can envisage some sort of Electric point infrastructure, a bit like Boris Bikes in London, it could only work for hybrids and in popular locations., and would seem to be very prone to chaos.

 

I struggle to work out how they are re-charging these things. I didnt quite catch the capacity of the lead acids on that 'crusing the cut link' but it must be 1000Ahrs+ bank. How do they recharge. If it takes 10 hours charging to replace 1hrs motoring then Electric point infrastructure just wouldnt work. You would have to be on the electric point for a couple of days to charge up for one days motoring. Imagine the queues!

Now if they were all lithium batteries (as Peter) then no problem as they take the full charge ALL THE TIME (and dont need to be full ever) and not this decreasing tail current which has to be done to get to full. No. It aint goin' to work.

[peterboat]

51 minutes ago, Dr Bob said:

I struggle to work out how they are re-charging these things. I didnt quite catch the capacity of the lead acids on that 'crusing the cut link' but it must be 1000Ahrs+ bank. How do they recharge. If it takes 10 hours charging to replace 1hrs motoring then Electric point infrastructure just wouldnt work. You would have to be on the electric point for a couple of days to charge up for one days motoring. Imagine the queues!

Now if they were all lithium batteries (as Peter) then no problem as they take the full charge ALL THE TIME (and dont need to be full ever) and not this decreasing tail current which has to be done to get to full. No. It aint goin' to work.

Same here Bob looked like a 24 volt system to me which would be say 600ah? it would easily run for a days cruising at say 25ah? [this is what my bathtub uses at 3mph] Me I would have solar on them which would on a sunny day cover its use I think

[IanD]

Think of it in Wh not Ah. If typical power when cruising is 3kW/4hp (reasonable assumption) then a standard 13A mains socket (3kW) would theoretically take an hour to put back the energy used up in an hours cruising -- actually allowing for all the charge/discharge/moter/controller inefficiencies, closer to 1.5 hours. Allowing for time spent at locks, this would just about work overnight but would be tight (12 hours charging) if you cruised all day (8 hours). And this doesn't allow for the time to drop the tail current down to fully recharge lead-acids.

 

So a higher capacity charge point rather than 13A mains would be preferable, just like for electric cars, but isn't absolutely essential.

 

You'd need a battery bank with getting on for 25kWh usable capacity, which means around 1000Ah at 48V (this is what the Hybrid Marine boats use) or 2000Ah at 24V using lead-acids to 50% capacity.

Edited April 17, 2019 by IanD

[ditchcrawler]

I couldnt open the link but was it his report on the Mon and Breck, if so you cant go that far anyway and at about 2 mph

[peterboat]

5 hours ago, IanD said:

Think of it in Wh not Ah. If typical power when cruising is 3kW/4hp (reasonable assumption) then a standard 13A mains socket (3kW) would theoretically take an hour to put back the energy used up in an hours cruising -- actually allowing for all the charge/discharge/moter/controller inefficiencies, closer to 1.5 hours. Allowing for time spent at locks, this would just about work overnight but would be tight (12 hours charging) if you cruised all day (8 hours). And this doesn't allow for the time to drop the tail current down to fully recharge lead-acids.

 

So a higher capacity charge point rather than 13A mains would be preferable, just like for electric cars, but isn't absolutely essential.

 

You'd need a battery bank with getting on for 25kWh usable capacity, which means around 1000Ah at 48V (this is what the Hybrid Marine boats use) or 2000Ah at 24V using lead-acids to 50% capacity.

They wouldnt use that much power I have a 24 volt system on the bathtub and it only draws 23 ah at 3 MPH it would drop even more at 2 mph, the hybrid systems have a higher draw because they are turning  the gearbox output shaft which is a lot of extra drag

[WotEver]

5 minutes ago, peterboat said:

it only draws 23 ah A at 3 MPH 

Fixed that for you. 

[IanD]

17 hours ago, peterboat said:

They wouldnt use that much power I have a 24 volt system on the bathtub and it only draws 23 ah at 3 MPH it would drop even more at 2 mph, the hybrid systems have a higher draw because they are turning  the gearbox output shaft which is a lot of extra drag

How big is the bathtub and what is the draft? 23A at 24V is only about 500W (2/3hp) at the prop assuming 90% motor efficiency, which doesn't seem enough to reach 3mph for even a small narrowboat in deep water.

Edited April 18, 2019 by IanD

[peterboat]

4 minutes ago, IanD said:

How big is the bathtub and what is the draft? 23A at 24V is only about 500W (2/3hp) at the prop assuming 90% motor efficiency, which doesn't seem enough to reach 3mph for even a small narrowboat in deep water.

The bathtub is a broads cruiser so lighter than a narrowboat it is 32 x 12 it has a cedric Lynch motor in it which in the DC motor world is as good as it gets, it is belt drive and can achieve 1000 rpm at the prop, which is right for the boat, google Cedric Lynch he is one clever guy. The boat doesnt draw much at all and the S and SY is deep very deep.

[peterboat]

I have been out in the big boat today, I am on my way to Sheffield, I have done two locks and been on the go for 1.5 hours the batteries were down to 92% as it wasnt very sunny. As I am single handed it has meant that at the locks the boat motor is turned off so batteries are charging from the solar but not a lot. Since I have moored up the sun is out and the batteries are now up to 96% so by morning they will be charged and ready for the off, I will see how it goes, but am hoping for a sunny day and high amps in

[IanD]

4 minutes ago, peterboat said:

The bathtub is a broads cruiser so lighter than a narrowboat it is 32 x 12 it has a cedric Lynch motor in it which in the DC motor world is as good as it gets, it is belt drive and can achieve 1000 rpm at the prop, which is right for the boat, google Cedric Lynch he is one clever guy. The boat doesnt draw much at all and the S and SY is deep very deep.

OK, that makes sense. For a typical 60'x7'x2' narrowboat 3kW/4bhp gives about 4mph in deep water and 3mph in a typical canal, which is normal cruising (when not passing moored boats or sitting in locks). So the requirement for a 800Ah~1000Ah/48V battery bank (over a ton of lead-acid!) for an electric narrowboat is still correct, the bathtub needs less than a quarter of this.

[peterboat]

13 minutes ago, IanD said:

OK, that makes sense. For a typical 60'x7'x2' narrowboat 3kW/4bhp gives about 4mph in deep water and 3mph in a typical canal, which is normal cruising (when not passing moored boats or sitting in locks). So the requirement for a 800Ah~1000Ah/48V battery bank (over a ton of lead-acid!) for an electric narrowboat is still correct, the bathtub needs less than a quarter of this.

Just over 2KW gives my 57 x 12 x 24 inch 3mph in deep water, I think a narrowboat would do better than me but thats for a future job as a mate want to convert his NB to electric

[IanD]

17 hours ago, peterboat said:

Just over 2KW gives my 57 x 12 x 24 inch 3mph in deep water, I think a narrowboat would do better than me but thats for a future job as a mate want to convert his NB to electric

All this shows how surprisingly little power you need for a boat on the canals, modern boats are massively overpowered -- except maybe for the rare case where you want to flog up a river against a strong current, which many people never do in their entire boating life. When we hired Keith Jones's steamer "Firefly" in the 1980s it only had about 3hp flat out and it still got us from A to B reasonably quickly, helped by a superb hull shape. But get onto a shallow canal and it really felt it...

[peterboat]

1 hour ago, IanD said:

All this shows how surprisingly little power you need for a boat on the canals, modern boats are massively overpowered -- except maybe for the rare case where you want to flog up a river against a strong current, which many people never do in their entire boating life. When we hired Keith Jones's steamer "Firefly" in the 1980s it only had about 3hp flat out and it still got us from A to B reasonably quickly, helped by a superb hull shape. But get onto a shallow canal and it really felt it...

All true Ian, I have come up Tinsley flight 3 .5 hours batteries at 97% at start 86% now, plus 1 kw coming into the bank as we speak, just have another 4 miles to go, and in todays sun expect to be fully charged by tonight.

[Paul HD]

Must be great to cruise along fairly silently. 

Would be great to see some video footage.

[peterboat]

6 minutes ago, Paul HD said:

Must be great to cruise along fairly silently. 

Would be great to see some video footage.

Next weeks job I think, I did a video today and its crap, so I will get my mate to do it while I drive

[Paul HD]

1 hour ago, peterboat said:

Next weeks job I think, I did a video today and its crap, so I will get my mate to do it while I drive

I look forward to that. ?

[MtB]

10 hours ago, IanD said:

When we hired Keith Jones's steamer "Firefly" in the 1980s it only had about 3hp flat out and it still got us from A to B reasonably quickly, helped by a superb hull shape. But get onto a shallow canal and it really felt it...

 

What did it stop like with only 3hp? This is where a dozen or so HP gets really useful.

 

 

 

 

[peterboat]

So taday after the solar had stopped charging I found I have used 8.2 kw to make the journey from Rotherham to Sheffield  not a lot in the way of things is it?

[Johny London]

Well done Peter! Saving the planet and boating - it's the way forward.

When you say 5 hours cruising - is that including when stationary at locks etc? You said something about turning the motor off? I presume that the great thing about having electric drive is that in actual fact, when the time is spent doing locks etc, you aren't using any power.

Put me down for one