electric boat calculation [Archive]

BertKu

05-24-2010, 12:57 AM

Have here someone that help me calculate range for possible electric boat calculation
480HP electric engines power (6 x 80HP electro engines)
Displacement empty appr. 55 tons

how much batteries I much have? count that is possible have 22 meters of batteries 3 lines of accumulators x 22 meters

How much will be generally range of yacht like this?

Note: pls. focus on answer.. no ask me where you will buy electro motors? or you have money buy it all and ask here etc. :D pls. no imagine any other 'movies'

who can answer seriously say---

1) 50Kw water cooled electro motors (67 HP) are available from http://www.propulsionmarine.com/price_list.htm

2) At present good technology, I would go for the Altair Nano technology

3) 22 meters x 3 = 66 meters would give you. Probably 1 Mw / 250Kwh battery-pack Maybe 2 battery packs from Alair Nano www.altairnano.com

4) You would do +/- 40 minutes with 6 x 50 Kw motors. Or just over an hour with 2 packs and with your engines.

5) My vision is that within 20 years , they will be on the sea, but with a different kind of battery system, not the one of today’s world.

6) Today we are restricted to small boats, with added solar and wind energy , we could go along the coasts and rivers, but not yet across the ocean. .

7) In your case you could go to 1000 Volt motoren to reduce the massive current flow..
Bert

gp333

05-24-2010, 01:13 AM

thanks for serious answer...

1) 50Kw water cooled electro motors (67 HP) are available from http://www.propulsionmarine.com/price_list.htm
RE: http://www.piktronik.com/index.php?option=com_content&view=category&layout=blog&id=20&Itemid=115&lang=en
here have 80HP electro motors water cooled too

2) At present good technology, I would go for the Altair Nano technology

3) 22 meters x 3 = 66 meters would give you. Probably 1 Mw / 250Kwh battery-pack Maybe 2 battery packs from Alair Nano www.altairnano.com
RE: what you mean by "2 packs"? How much batteries is 2 packs generally?

4) You would do +/- 40 minutes with 6 x 50 Kw motors. Or just over an hour with 2 packs and with your engines.

5) My vision is that within 20 years , they will be on the sea, but with a different kind of battery system, not the one of today’s world.
RE: :-(
http://www.electric-boat-association.org.uk/
Four 250 ton Rolls-Royce Mermaid™
electric propulsion pods totalling
86 Megawatts drive the QM2
along at almost 30 knots.

and Queen Mary 2 - She's the
world's largest electric boat !

What engines are here in case?

Is this electric engine too?
http://www.rolls-royce.com/marine/products/propulsors/podded/index.jsp

6) Today we are restricted to small boats, with added solar and wind energy , we could go along the coasts and rivers, but not yet across the ocean. .
RE: yes solar can be added.. but voltage can be charged in marinas too

7) In your case you could go to 1000 Volt motoren to reduce the massive current flow..
RE: hm explain additional this?

BertKu

05-24-2010, 01:38 AM

thanks for serious answer...

My apology, I thought you were only thinking of pure battery energy. The Q2 has diesel engines with electric generators , which feeds the electro motors I assume. That is a different ball game. You need to ask a NA about the construction.

BertKu

05-24-2010, 01:56 AM

7) In your case you could go to 1000 Volt motoren to reduce the massive current flow..
RE: hm explain additional this?

GP, there are two methods to run your propulsion.

1) You have Direct Current motors, (DC), but because if you exceed the 48 Volt and have a 200 Volt DC system and you would touch between the + and minus, you are dead. Your hands will cramp, it will not be able to let go and you will die. Therefore on an electric boat it is not recommended to go over 48Volt DC.

However you could convert the (DC) battery voltage via an inverter and keep the heavy current cables short , close to the battery and bring the Voltage up to 300 Volt AC (Alternating Current) and if you now touch a part, you have a hell of a shock, but probably will survive, provided the body resistance is high enough to let less than 20 MilliAmpere to go through your hart.

Thus, if you have 48 Volt motors / 50 Kw, it means a direct current of just over a 1000 Ampere from your battery. Your cables will have to be at 6 Ampere per mm2 , massive. Your losses are therefore also high.

If You have a dieselgenerator and you generate 1000 Volt AC, your current at the 50 Kw motor is only 50 Ampere and that is about 10 mm2, but better to be 16 mm2 to keep the losses low. Most likely QE2 will have high Voltage motors like they use in the mines, greater than 10 KVolt (just to keep the current low)
Bert

gp333

05-24-2010, 05:00 AM

I was mean pure battery energy too. If we have dieselgenerator we again must use same amount of diesel like we have diesel boat engines? Or this solution have lot lower diesel fuel usage?

You are not answer me this below:
3) 22 meters x 3 = 66 meters would give you. Probably 1 Mw / 250Kwh battery-pack Maybe 2 battery packs from Alair Nano www.altairnano.com
RE: what you mean by "2 packs"? How much batteries is 2 packs generally?

Regarding higher voltages.. sure it can make dead, but connectors will not be opened to hand touching! They will be isolated and you cant touch directly at all! I am looking any solution but that calculation make possible over ocean trip. Can you show any calculation that can realize it maybe? count that we can have lot batteries really...

BertKu

05-24-2010, 05:21 AM

I was mean pure battery energy too. If we have dieselgenerator we again must use same amount of diesel like we have diesel boat engines? Or this solution have lot lower diesel fuel usage?
It is convenience, ONE big diesel engine and possible 20 or whatever electric motors. Most likely it could save some diesel, but it will be for debate. I think
it is just the control from a central point and convenience in my view. An electro motor has 2 bearings, that is all, no battery to start up, no drive belt to make it to start up etc. Convenience to me for the Captain of the QE2

You are not answer me this below:
3) 22 meters x 3 = 66 meters would give you. Probably 1 Mw / 250Kwh battery-pack Maybe 2 battery packs from Altair Nano www.altairnano.com
RE: what you mean by "2 packs"? How much batteries is 2 packs generally?

This depends on the voltage of the motor, how many batteries are in serial and parrallel, there is no generally. A small boat can run on 3 or 4 big single batteries and a bigger boat needs maybe 16 batteries 4 x 4 parallel / serial. However in your case you have to calculate what Voltage and current is required. Those Altair packs are massive packs for solar energy installations. You have to visit Altair website for dimensions.

Regarding higher voltages.. sure it can make dead, but connectors will not be opened to hand touching! They will be isolated and you cant touch directly at all! I am looking any solution but that calculation make possible over ocean trip. Can you show any calculation that can realize it maybe? count that we can have lot batteries really...
Yes, but I would not take the risk on a boat which moves and is not stable. At one stage you need to work on it without the insolation.
I don't think you are able at this present time to consider a trip with batteries only. You need Diesel/generating power.
Bert

BertKu

05-24-2010, 05:35 AM

To enable you to travel with a total of 480 Hp engines i.e. 360 Kw and assuming your speed is 36 Km per hour (displacement boat) and the distance accross the ocean is 3600 km , you need (3600 divided by 36) x 360 Kw = 36.000 Kwhour i.e. 36 Megawatthour. That is 36 massive Altair Nano packs You need probably to tow a QE2 to store those batteries.

I like you, keep on having a vision or dream, nothing wrong with that. At any time you can ask more direct questions, if it is still unclear.

Bert

Pierre R

05-24-2010, 05:38 AM

gp333

05-24-2010, 06:46 AM

A rough guess would be needing 85,000 watts to drive a 55 ton boat of that length about 10 NM. A rough guess on 22 meters of batteries in three lines would give 47,000 amp hours. Now to drive the boat 10 NM you would need 6,900 Amp hours. You would not want to discharge to more than 50 % so that means about 34NM before recharge.

This is assuming a displacement speed in knots equal to the square root of the water line length in feet. This is also assuming a lead acid type of battery.
ha it seems possible! :o we can have 9 lines of batteries as example :)
any idea how much cost so lot batteries generally?

how much time need it charge it by classic voltage connector in port?

how much time generator can charge batteries too?

and addon is solar power on roof as example, 15 meters x 3 meters of solar cells: I am happy if this can cover electricity for rooms and living people on boat. Can this cover it?

gp333

05-24-2010, 07:04 AM

gp333

05-24-2010, 07:15 AM

I cant have more than 10 tons of batteries (in 55tons of displacement I was count inside these 10 tons)
than this is 10.000 Kwhour and if I understand good this is 1000km range?
Pls. confirm?

gp333

05-24-2010, 07:22 AM

Shortest points over Atlantic ocean is 2,575 km

BertKu

05-24-2010, 09:04 AM

I cant have more than 10 tons of batteries (in 55tons of displacement I was count inside these 10 tons)
than this is 10.000 Kwhour and if I understand good this is 1000km range?
Pls. confirm?

Hi gp, but then you must come down with your 460KW motors to something more realistic, like 85 Kw motors, like PiereR suggested. But with 85 Kw it also only bring to not more than 10.000 Kwh divided by 85 = 117 x 10 Nm = approx 2000km. You need like safety in an aircraft at least 50% reserve, otherwise you deepcharge the batteries. You sure like to ensure some reserve for the unforseen? But the most important question is how are you going to re-charge the batteries at the other end of the world? You may only get an 25 Ampere wallplug and you could maybe only charge with single phase. It can be done, but it is too risky.

PierreR with what Voltage did you make the assumptions.
Bert

gp333

05-24-2010, 09:22 AM

Hi gp, but then you must come down with your 460KW motors to something
more realistic, like 85 Kw motors, like PiereR suggested. But with 85 Kw
it also only bring to not more than 10.000 Kwh divided by 85 = 117 x 10
Nm = approx 2000km.
RE: I see that minimum need be 4 motors x 80HP (320HP) by 55 tons vessel, because bad weather conditions etc.
But sure we must not plan full power all the time. Sure construction like that can have on/off switch motors, and simple shut down
2 motors in some moments etc. And with other 2 use 50% of power and in this moment you use 80HP as example...

yes, and maybe is for project 1 must not be over ocean availability, but with above availability you can use vessel in lot other locations.. practically all except over ocean!
this is good enough that project not be only 'dream'...

You need like safety in an aircraft at least 50%
reserve, otherwise you deepcharge the batteries.
RE; yeh I see

You sure like to
ensure some reserve for the unforseen? But the most important question
is how are you going to re-charge the batteries at the other end of the
world? You may only get an 25 Ampere wallplug and you could maybe only
charge with single phase. It can be done, but it is too risky.
RE: why risky not understand? I assume that I can charge batteries at any marina usual voltage plugin! Is not problem stay more hours till all loaded...
what wrong here now?

and addon is solar power on roof as example, 15 meters x 3 meters of
solar cells: I am happy if this can cover electricity for rooms and
living people on boat. Can this cover it?

apex1

05-24-2010, 03:22 PM

How much will be generally range of yacht like this?-

Zero...........

Get It Goran,

there is NO electric propulsion on the market for a vessel that size!

IT DOES NOT EXIST !

was that clear enough?

And to qoute parts of your mail:

As we are looking for minimal cost... we wish not so custom build
that someone must for us create whole mold again.... We are talk
here, in hope that you can build yacht for us by minimal cost and in
co-operation with me..

and:

They plan create electric engine boat (exist all electric equipment on market; but must be 6 -8 smaller electric engines with 6-8 propellers, because no exist so high power electric engine)

6-8 props are really crazy (as the entire plan) and..
..... there are much larger el. motors on the market than you ask for. But it is not true that a 480hp el. motor can substitute a 750hp Diesel, as you stated. When 750hp are required you have to install 750hp! The higher torque of the el. motor is no substitution for the lower power.

But then:

and we'll be solar panels on hard top on last level.. I fully know that I must have experienced solar/electric engineer by this project included.. your shipyard must not do all... I can add own man that be part of team to manage electric stuff..

......the bubble bursts, that is not possible.

And when we look at the boat of your dreams*** a displacement of 55 tonnes is not real. It is more likely 120 tonnes. And it does not carry the batteries one would need (who would buy them btw. when you are on a tight budget?)
***see attachment

The QM2 you mentioned is Diesel Electric of course. But Cruiseships have a Hotel load which is almost as high as the propulsion power. In a yacht that has no sense.
And again it does not correspond whith low budget.

This post probably enlightens you a bit, as it did enlighten another dreamer.
http://www.boatdesign.net/forums/boat-design/did-dream-got-shattered-32801-6.html#post367820

Regards
Richard

gp333

05-24-2010, 03:33 PM

but you see answers of other people.. and step by step we have good range

and we say 4 propellers now or transmission 4 to 1

btw. see real solutions: 1st image is electric/diesel boat with 4 propellers

and I have other solutions for hull (lighter than one of plans you attach here when i talk with you)

simple start talk with numbers.. because that i stop by email change your mind.. :-) you see that these other persons here talk with some numbers... if you have something say you must talk with some calculations.. other lose my, your energy and time only

gp333

05-24-2010, 03:39 PM

This post probably enlightens you a bit, as it did enlighten another dreamer.
Did a dream got shattered?
http://www.boatdesign.net/forums/boat-design/did-dream-got-shattered-32801-6.html#post367820

RE: yes I read it :-) but anyway this is all not so 'black'... must be more positive :-))

Democracy is still one small step higher than in Victorian time too! But we still wish be live.. and we live..

apex1

05-24-2010, 04:14 PM

but you see answers of other people.. and step by step we have good range

The comments of another novice in this field will not bring you any further, I fear.

and we say 4 propellers now or transmission 4 to 1

btw. see real solutions: 1st image is electric/diesel boat with 4 propellers

You did not ask for Diesel Electric! You wanted a fully electric megayacht, that is not available! And the "Boat" shown is a commercial vessel with a Azipod drive, they cost more per piece than a complete Diesel propulsion would. The other vessel sports Arneson drives in a pretty doubtful arrangement (and still only 4 not 8)

and I have other solutions for hull (lighter than one of plans you attach here when i talk with you)

You do not have any solutions for hulls which I would´nt have already, thats nonsense.

simple start talk with numbers.. because that i stop by email change your mind.. :-)

Oh no guy YOU did not stop anything!!! I cancelled with you, due to the absolutely premature, stubborn and dubious approach.

I SAID FORGET IT, not you.

you see that these other persons here talk with some numbers... if you have something say you must talk with some calculations.. other lose my, your energy and time only

There are no numbers to talk. One cannot provide numbers of non existant rubbish.

Landlubber

05-24-2010, 04:25 PM

gp333

05-24-2010, 04:31 PM

btw. see real solutions: 1st image is electric/diesel boat with 4 propellers

You did not ask for Diesel Electric! You wanted a fully electric megayacht,
RE: hm, 80 till 100 feet is not so 'mega yacht at all.. more like middle higher range... and must not go over ocean.. I was say it on start of post here.. for my project must not have 'ocean range'

that is not available! And the "Boat" shown is a commercial vessel with a Azipod drive, they cost more per piece than a complete Diesel propulsion would.
RE: yes, but I answer here only this to you: that 4 propellers constructionally exist! You talk that this is not possible to me too.. but is possible... have other examples on web.. pls. change ming here than :-) and say: yes, 4 propellers can go.......

and I have other solutions for hull (lighter than one of plans you attach here when i talk with you)

You do not have any solutions for hulls which I would´nt have already, thats nonsense.
RE: you see in 2 my images that 4 propellers can go on these 2 hulls.. and be sure they can go on lot other hulls..
but I was say it few times. 4 engines can be connected in one propeller too

than we can stop talk about this and focus on electric problems

simple start talk with numbers.. because that i stop by email change your mind.. :-)

Oh no guy YOU did not stop anything!!! I cancelled with you, due to the absolutely premature, stubborn and dubious approach.

I SAID FORGET IT, not you.
RE: I am not so 'important' and here person with experience.. yes, you say you cant do it... but I am stop talk about that latter with you more... but you here start talk.. you see, these 'small details' change story.. and angle of look very often in life..
btw. I count you as friend :-) because I have potential investor for electric boat project is my own problem.. I talk here about basics... if anyone is more experienced here he can start be part of project. As I was say you this is possible nonprofit project and possible obtain budget to create some real solution. if this be ok, as it is nonprofit be sure I will share some real project calculations with people here in future...

BertKu

05-24-2010, 04:45 PM

One cannot provide numbers of non existant rubbish........

like it or not, this is a true statement......maybe one day we will have some source of electric power that can handle the required high amperage for prolonged periods, currently it simply does not exist, and going on as if it was going to happen next week is absolute rubbish....watch the auto world for the most up to date versions so far....we have a long way to go.

Hi Landlubber. I am absolute flabbergasted by your reply. Do you know that in your own country a solar ferry (lots of cars) is already sailing for years. I have posted last year pictures on this net. De autoworld is holding progress back due to vast investment they have. But other interested parties will push the automative industry aside with lobbying the governements and you will see some progress in the years to come.
Bert

Pierre R

05-24-2010, 04:49 PM

I gave real numbers using lead acid batteries. The most affordable battery out there. For 34 nm of range at a discharge of 50% the batteries would weigh close to 15 tons.

To cross the ocean would require 750 tons of batteries at current prices of about 2.2 millon dollars worth of batteries. Now the power requirement was for 55 tons. 750 tons would require 13 times as many batteries in a never ending spiral. There is no way on this planet that you are crossing an ocean with a 55 ton boat on battery power.

The biggest dock hookups are 240 by 100 amps. To recharge the batteries at shore would take approximately 770 hours or 32 days with no other power usesage on board.

This does not sound too practical to me. In fact it sounds totally impossible. Only our current crop of politicians would try anything like this.

apex1

05-24-2010, 04:58 PM

RE: yes, but I answer here only this to you: that 4 propellers constructionally exist!
...

Never I said there are no vessels with 4 props. You asked for 6 to 8 props, and that is nonsense period.

I did inform you that I am not interested in building a motorboat for you. I said: forget it.
In a second mail on your other (as dubious) enquiry for the sailing boat I just informed you that I do´nt make sailing boats.

Your plan is surreal to a unbelievable extend and your enquiries dubious, amateurish and doubtful.

No reason to comment any further.

gp333

05-24-2010, 05:05 PM

I gave real numbers using lead acid batteries.
RE: yes, you Pierre R help me imagine generally how this calculation go.. sure original plan must be adjusted on few elements, but all is still "open" here and I can change my plan based on real numbers...

The most affordable battery out there. For 34 nm of range at a discharge of 50% the batteries would weigh close to 15 tons.
RE: yes, I see... this is not so problem... count that usually you have similar diesel tanks loaded. This is 5 tons more than I plan, but is not so higher!

To cross the ocean would require 750 tons of batteries at current prices of about 2.2 millon dollars worth of batteries.
RE: yeh.. I see... on any way, I was say on start.. 'cross ocean' range must not be here present at all

Now the power requirement was for 55 tons. 750 tons would require 13 times as many batteries in a never ending spiral. There is no way on this planet that you are crossing an ocean with a 55 ton boat on battery power.
RE: sure

The biggest dock hookups are 240 by 100 amps. To recharge the batteries at shore would take approximately 770 hours or 32 days with no other power usesage on board.

This does not sound too practical to me. In fact it sounds totally impossible. Only our current crop of politicians would try anything like this.
RE: yeh..and finally: what is possible range if we have 15 tons of batteries, 80-100HP engine and 55tons displacement?

gp333

05-24-2010, 05:09 PM

Never I said there are no vessels with 4 props. You asked for 6 to 8 props, and that is nonsense period.

I did inform you that I am not interested in building a motorboat for you. I said: forget it.
RE: yes , I agree.. exactly happen like that

In a second mail on your other (as dubious) enquiry for the sailing boat I just informed you that I do´nt make sailing boats.
RE: yes, and I have serious request and client there

Your plan is surreal to a unbelievable extend and your enquiries dubious, amateurish and doubtful.
RE: why? because I ask about technology that still not fully realized in reality? who are you and what you know about me? you are some "judge of boats II" here :-)?

No reason to comment any further.
RE: yes, because that I STOP this type of talk by email and you STOP technical hull building part of talk

we so clear know what we do that it is great :-)

Pierre R

05-24-2010, 07:11 PM

RE: yeh..and finally: what is possible range if we have 15 tons of batteries, 80-100HP engine and 55tons displacement?34NM at 50% discharge. My numbers matched yours in my figures.

What you have to realize is that 15 tons of batteries equals about 17 gallons of diesel. The diesel will weigh 120 lb or 55kg. To generate the electricity to recharge the batteries requires about 75 kg of coal. 75kg of coal produces roughly twice as much greenhouse gas as 17 gallons of diesel.

You could recharge with say 80 solar panels. That would give you a recharge period of about a week. Then you could go another 34 NM.

The panels would only cost about $ 35,000 US. Even on your side of the pond the diesel will only cost $125 US. Even at bank deposit interest rates of 2% the $35k will generate about $60 US per month or half the cost of the $17 gallons of diesel.

At present the cheapest diesel electric setups cost at least twice what a conventional diesel setup would cost and only runs about 90% as efficient most of the time. The main advantage is electric/drive power management of a boat with heavy electrical loads. In that setup the diesel electic can match or best the diesel only drive system.

gp333

05-24-2010, 07:29 PM

Pierre R

05-24-2010, 07:53 PM

yeah Pierre R you really answer me great and give 'picture' of all

we are say all I ask in fact.. but I have curiosity.. by your opinion what is possible range if we have 15 tons of batteries, 80-100HP engine and 55tons displacement?

100km? 500km? or use miles same (I mean from 100% till 50% batteries level)
interesting is after all talk see some reasonable real numberListen very carefully. The practical limit is 34NM. That is with a boat about 100 feet long (31m) by say 16' beam or (4.9 m), pinched at the stern to give a prismatic coefficient near 0.58.

Now you could slow it way down from there but in real practice there is somewhat of a diminishing return down low due to wind, waves and current. If you slow the boat down to say 6 knots you might get say 100NM 185KM

The fact still remains. The 55 tons you have in mind is still way to heavy and comfortable for what you have in mind. You need something more in the range of 20 meters and a weight of 8 tons. You can carry you, a bucket, a toothbush, one change of cloths and a jerry can of water and some Raman noodles after spending north of $500k.

Pierre R

05-24-2010, 07:55 PM

yeah Pierre R you really answer me great and give 'picture' of all

interesting is after all talk see some reasonable real numberI personally think there is absolutely nothing reasonable in the numbers I am giving you.

gp333

05-24-2010, 07:56 PM

:-) ok tnx

Pierre R

05-24-2010, 07:59 PM

For about $600k Euros plus killer VAT tax you can buy something so so off the shelf http://www.greencarcongress.com/2008/08/island-pilot-to.html

gp333

05-24-2010, 08:09 PM

sure I know about Steyr Motors Serial Hybrid Propulsion too!

see this one system too: http://www.greenlinehybrid.com/?id_g=6

apex1

05-25-2010, 10:47 PM

sure I know about Steyr Motors Serial Hybrid Propulsion too! ]

And....

does it matter if you know about one (insufficient) hybrid system?

You asked for a fully electric driven 120 tonnes vessel! Your childish 55 t estimation was just another proof of your amateurish approach.

Forget it, it does not exist!

Even if your funds were already raised, even if they were sufficient to finance a vessel of this size (from 10 mio € upwards), there is NO WAY to get where you want to go.

A Diesel Electric propulsion is about twice the cost of a conventional. A so named hybrid (which is a combination of D / E and batteries / inverters, is about 3 times the conventional.

And you are on a budget!

Go and dream elsewhere.

Your approach is a fake Goran! A lie. Not just a dream. You try to F%$ck someone, do´nt get us involved.

Regards
Richard

kerosene

05-26-2010, 01:28 AM

Jeremy Harris

05-26-2010, 01:48 AM

apex is of course right if a little harsh on innocent dreamers.

Hybrid on a boat is not much other than fashionable hyped nonsense. Hybrids work great for on land vehicles in traffic where the engine output needs to be sized for occasional acceleration (very high power) but most of the time the power need in cruising is way below that. Add generative braking and you have something.

Boats work in very different conditions - there is no "waste" energy in same way as in cars/trucks.

Very true.

The key to making a hybrid system work in any environment is the peak to average power ratio. For land vehicles this ratio is high - the Toyota Prius, for example, has a peak power of 134hp, but only uses on average about 15hp, giving a peak to average ratio of nearly 9:1.

Such high ratios allow the option of using a primary power source (ICE) that is only capable of delivering around 11% to 12% of the peak power requirement (although the Prius ICE is much bigger than this) and relying on the battery back and much more powerful electric motor to deliver the short duration peak power bursts.

The majority of boats (and aeroplanes, for that matter) are completely different in terms of their power requirements. Their average power requirement may be around 50% to 70% of their peak power requirement, or in other words a peak to average ratio of 1.5 to 2:1. This makes a hybrid system of very limited, if any, advantage, as the additional losses from the extra power conversion steps (ICE > electricity > battery > electric motor) would outweigh any minor saving from reducing the size of the primary power plant.

Jeremy

Pierre R

05-26-2010, 04:54 AM

There are very ligitimate uses for diesel electric propulsion but most of them revolve around commerical uses.

I have seen some enthusiasm for trying to justify diesel electric hybrids or electric boats based on wanting to be green or save the planet. These folks, like people who play the power ball lottery, are basically people who are not very good at math or science.

Now a bass boat is a good use of petrol electric blend.

Guest625101138

05-26-2010, 05:15 AM

Very true.

The key to making a hybrid system work in any environment is the peak to average power ratio. For land vehicles this ratio is high - the Toyota Prius, for example, has a peak power of 134hp, but only uses on average about 15hp, giving a peak to average ratio of nearly 9:1.

Such high ratios allow the option of using a primary power source (ICE) that is only capable of delivering around 11% to 12% of the peak power requirement (although the Prius ICE is much bigger than this) and relying on the battery back and much more powerful electric motor to deliver the short duration peak power bursts.

The majority of boats (and aeroplanes, for that matter) are completely different in terms of their power requirements. Their average power requirement may be around 50% to 70% of their peak power requirement, or in other words a peak to average ratio of 1.5 to 2:1. This makes a hybrid system of very limited, if any, advantage, as the additional losses from the extra power conversion steps (ICE > electricity > battery > electric motor) would outweigh any minor saving from reducing the size of the primary power plant.

Jeremy

Jeremy
Not only the peak to average but the benefit of energy recovery in braking particularly in stop-start traffic.

From what I have seen in a few places around the world the Prius and hybrid Camry are making big inroads into the taxi industry. I have heard that the maintenance costs are also lower due to reduced wear and tear on braking and smoother transmission.

Anyhow none of these benefits apply to boats.

I have no doubt that solar-electric boats are technologically possible for crossing oceans but such boats do not look much like existing cruising boats. I expect maybe 10 years or more before they are in common use.

Rick W

Jeremy Harris

05-26-2010, 09:06 AM

Jeremy
Not only the peak to average but the benefit of energy recovery in braking particularly in stop-start traffic.

From what I have seen in a few places around the world the Prius and hybrid Camry are making big inroads into the taxi industry. I have heard that the maintenance costs are also lower due to reduced wear and tear on braking and smoother transmission.

Anyhow none of these benefits apply to boats.

I have no doubt that solar-electric boats are technologically possible for crossing oceans but such boats do not look much like existing cruising boats. I expect maybe 10 years or more before they are in common use.

True, regenerative braking does add a bit to efficiency, but only around 8% of the energy used is actually recovered by regeneration by the Prius. I think that the main reason that taxi companies like them is the low servicing cost, low running cost and high reliability, as much as anything else. Another reason here in the UK for them being attractive as taxis is that they are zero rated for road tax and don't pay the daily congestion charge in London (currently £8 (~$12 US) per day.

I have looked at using regenerative charging on a boat, using excess energy when sailing, or when moored in a tideway, to generate power, but the gains don't look to be too good overall.

Jeremy

pvgenesis

07-08-2010, 09:50 AM

Hi everybody,
This is my firts post here and I have to say that I know almost nothing about boat designing!
However, I've studied electronics and I work many years now in the off-grid solar market both designing systems and installing them.
I've run into your forum and this post by accident, while searching for something else in the internet and I find gp333's project quite interesting, although it is very optimist and not easy at all.

I have some ideas about solar/off-grid technology integration into vessels which may help this conversation.

- Talking about vessels, for safety reasons, it would be wise not to rely only on the stored into the batteries energy! We need to have a back-up, a controlled power source. A generator! even a small one.
- The key point is the efficient power and energy management. We can have a generator running for a few hours in its efficient point of operation in order to run our loads (whatever they are) and to store the surplus energy in the batteries at the same time. Once the batteries are charged we use the stored energy to run our loads. The advantage is especially during the low-cunsumption periods where we don't have a large generator running insufficiently just for e.g. the lighting and a TV set!
- The current commercial off-grid technology is capable of handling power up to 300kW (230/400V, 50Hz), the way I described above. Electric motors with a continuous demant of up to 200kW (~260bhp) can be driven by such a system.
- Such a system weights something like 5 - 10 tons (depending on the battery bank total size and type) and needs more than 40m2 of space in the engine room. this is not a system for small boats. However, it can be smaller e.g. at 100kW / 130bhp.
- The system is capable of handling many different power sources such as a large 3-phase generator, a solar array, wind turbines, other DC power sources and shore power. Everything operates automatically (including the start / stop of the generator) and the operator can monitor everything on a PC.
- I would say that it could be the ultimate solution (in terms of fuel / energy saving)for medium vessels that do small trips and stay stable for larger periods e.g. small car ferries that connect narrow channels of less that 2 or 3NM and stay stable for more than 30 min.

- I have a good knowledge of the electrical part but I know only a few about vessels!

Hope I helped a bit!

gp333

07-08-2010, 10:19 AM

great to see that someone have some electrical knowledge. Can you calculate how much two 50 Kw "eat" energy when work 2 hours and if 40m2 solar cells add energy into system at same time?

pvgenesis

07-08-2010, 11:52 AM

- 2 x 50kW x 2h would consume 200kWh of energy + loses.
- 40m2 of solar panels is about 5kWp of nominal power. It can produce 20 to 30kWh per day in a full sunny day with no shadows.

gp333

07-08-2010, 11:59 AM

Jeremy Harris

07-08-2010, 12:02 PM

great to see that someone have some electrical knowledge. Can you calculate how much two 50 Kw "eat" energy when work 2 hours and if 40m2 solar cells add energy into system at same time?

If you run two 50kW motors at full power, then they will consume 100kW of power per hour. If you assume that cruise power will be 60% of full power (probably a reasonable assumption) then you'll need to provide 60kW per hour.

The maximum insolation of the earth's surface in full sunlight is assumed to be around 1kW per square metre. Typical solar cell efficiency is around 16 to 18% at the moment, so you will get a maximum power, in full sunlight, of perhaps 180 watts per square metre. 40m² of solar cells will give you a maximum power of around 7.2kW.

As a rule of thumb, you need to derate this maximum figure as you will rarely, if ever, get full sunlight on all the panels, at an angle that will generate maximum power. In Northern latitudes (around 51 deg N) I've found that I get maybe 30% of the panel rated output, so if you used this as a working assumption then you would get somewhat over 2kW of usable output per hour, during daylight hours.

There would be a massive shortfall between your power demand and the output from your solar array, so I doubt that it makes sense to use such a system.

At the moment, the only practical way to use solar power on a boat (other than indirectly by using sails) is to design a hull that has a very low propulsion power requirement and enough area to fit cells that will cope with the power demand.

Jeremy

Jeremy Harris

07-08-2010, 12:14 PM

Altairnano batteries have this ratio: 1kw/kg

This mean 200kg of batteries = 200kWh
and if we wish not go below 50% in batteries we must have 400kg batteries for 2 hours full work? Is this right continue of your calculation?

This figure of 1kW/kg doesn't mean anything, the figure you need will be in kWh/kg. Currently, the best available batteries in terms of energy density (lithium) are around 0.6kWh/kg, so to meet your probable cruise power demand of 60kW you would need around 100kg of batteries per hour of cruise time, plus a derating factor for peukert factor (probably around 110% for typical high rate lithium technology cells)..

If you want to run at full power (100kW) then you would need around 167kg of cells per hour, plus the factor as above.

These figures assume 100% discharge, which will seriously impact cycle life. If you want the batteries to last for a few thousand cycles then you need to reduce the effective capacity by maybe 50%, doubling the weight of batteries needed per hour.

kerosene

07-08-2010, 12:22 PM

Altairnano batteries have this ratio: 1kw/kg

This mean 200kg of batteries = 200kWh
and if we wish not go below 50% in batteries we must have 400kg batteries for 2 hours full work? Is this right continue of your calculation?

1kwh / kg ???
That is such an outrageous claim that it either has to be a mistake or deceitful claim by the company.

I consider this a decent deal and performance for modern batteries:
http://elitepowersolutions.com/products/product_info.php?cPath=27_29&products_id=118

I am sure that some more exotic ones can beat that but at higher price. On above link the pack weighs 36kg for 3kwh pack. And that is modern LiFePM pack.

If 1kg/1kwh was true I would be building 20kwh e-motorbike as we speak.

gp333

07-08-2010, 12:53 PM

This figure of 1kW/kg doesn't mean anything, the figure you need will be in kWh/kg. Currently, the best available batteries in terms of energy density (lithium) are around 0.6kWh/kg, so to meet your probable cruise power demand of 60kW you would need around 100kg of batteries per hour of cruise time, plus a derating factor for peukert factor (probably around 110% for typical high rate lithium technology cells)..

If you want to run at full power (100kW) then you would need around 167kg of cells per hour, plus the factor as above.

These figures assume 100% discharge, which will seriously impact cycle life. If you want the batteries to last for a few thousand cycles then you need to reduce the effective capacity by maybe 50%, doubling the weight of batteries needed per hour.

after all philosophy, ok, this is best calculation on this post till now :-))

To conclude: If we want to run at full power (100kW) then we need around 350kg of cells per hour!
but this is not so lot... as I was say on start.. by my construction where I think between power yacht and sailing yacht. Keel have 6 tons only.
If I go to power boat project, I must not buy "mast+keel" and this is lot money too.

I can go with 6 tons of batteries... this is 17 hours of work by full power. if this is true than it is great calculation

gp333

07-08-2010, 01:04 PM

1kwh / kg ???

I am sure that some more exotic ones can beat that but at higher price. On above link the pack weighs 36kg for 3kwh pack. And that is modern LiFePM pack.

If 1kg/1kwh was true I would be building 20kwh e-motorbike as we speak.

I was read here: http://en.wikipedia.org/wiki/Altairnano

gp333

07-08-2010, 01:11 PM

if "12kg for 1kwh" is best right ratio kwh:kg than we have calc is lot less optimistic:

1.5 hour in full speed :-)))

kerosene

07-08-2010, 01:48 PM

Jeremy Harris

07-08-2010, 01:59 PM

Nissan Leaf's battery per wikipedia.

"The battery and control module together weigh 300 kilograms (660 lb) and the energy density of the cells is 140 W·h/kg" (battery is 24 kwh)

and continues:

"It is estimated that each battery pack costs Nissan $18K and expected to be half as much when mass production of the battery packs begins."

Now I would guess that that is about as optimum as today's technology and big production runs allow.

I know Jeremy knows his electric stuff and wonder if his 600wh/kg is more theoretical for the chemistry than realistic in real pack.

You're right, this is the theoretical capacity for raw cells, with no battery management system, no safety enclosure and no wiring. The real world, practical energy density is a fair bit lower.

This whole project seems wholly impractical using current technology, so I didn't bother to correct the figures for all the parasitic weight in the battery pack. The astronomical cost of a lithium battery weighing tonnes, plus the immense complexity and cost of a battery management system to control it, makes the idea wholly impractical.

Jeremy

pvgenesis

07-08-2010, 02:41 PM

Talking about batteries, I wouldn't choose anything else than conventional, flooded, deep cycle, lead acid batteries. It is the best performance for a reasonable price, they are reliable and they can stand "hard" treatment.

A typical 48V array that stores up to 20kWh in full charge weights about 0.8 tons.
For 200kWh we would need 10 times more which means 8 tons.
It is not too much but it is not light-weight.

Having a large battery bank is always good for such a system, but the key is - again - the power and energy management.
just like in the hybrid cars, we need the battery to take over the loads during the long, low consumption periods and to be used as an energy "buffer" during the short and high consumption periods with the engines working while cruising.
With such a usage, the battery is not necessary to be very large.

gp333

07-08-2010, 03:11 PM

Having a large battery bank is always good for such a system, but the key is - again - the power and energy management.
just like in the hybrid cars, we need the battery to take over the loads during the long, low consumption periods and to be used as an energy "buffer" during the short and high consumption periods with the engines working while cruising.
With such a usage, the battery is not necessary to be very large.

Yes this is good idea too... on any way if we add in system generator he can work in these moments as example. On any way by diesel engine, diesel work all the time.. this approach with temp generator work in right moments can help one step

alanrockwood

07-10-2010, 01:14 PM

I hope this is not hijacking the thread, but I am wondering about the possibility of using a plug in hybrid diesel electric power system for cruising inland waterways, such as the canals of France, in a replica barge fitted out as a pleasure craft.

I am speaking here from a very inexperienced and speculative point of view, but here is what I am thinking.

First, most canal cruising is going to be done for only a few hours per day under power, so the amount of kWhr used for propulsion in a day would typically be relatively modest.

Second, in a lot of cases shore power may be available, which could be used for recharging the battery bank, and when shore power is not available the on-board generator (which would need to be pretty hefty) could be used for recharging the battery bank.

Third, most cruising is done at a low speed and wouldn't require too much power, so one could probably get away with a relatively modest sized diesel powered generator and perhaps a medium sized or medium large battery bank.

Fourth, the on board generator could be used to augment the battery power when one needed to really goose the power level, such as when crossing a less protected waterway or when traveling on a river, or when the battery power got a little low.

There is, of course, the issue of cost, and likely the issue that an appropriate system is probably not commercially available, though the Steyr hybrid system might be pretty close in concept. Let's tackle the issue of cost first. It would no doubt be very expensive, but the possible energy savings alone (e.g. using cheaper electric power rather for most of the cruising energy rather than expensive diesel fuel with road tax applied) would probably allow the system to pay for itself in... well I dunno, maybe a thousand years or so. Maybe in that sense it is not practical, but look at it another way. A pleasure boat itself, regardless of type, would pay for itself, in the best case, in maybe..., well again I dunno how long, but the best guess would be never.

So it really comes down to pleasure derived from owning and using the boat. For some people owning a boat with a whiz-bang gizzmotron power system might be a significant part of the pleasure in owning a boat. For others, probably most boat owners, there would be, at most, a limited interest in this kind of thing.

Now let's tackle the issue of availability of a system............ hm........ anybody know anything about this issue?

By the way, if this would go better in a different thread just say so and I will start the conversation in a different thread.

One more thing added after the original post: the weight of the battery bank is probably not much of an issue here, at least not if the craft was designed with this in mind from the beginning. The boat would probably be designed so the weight and placement of the battery bank would just count toward the ballast budget of the boat.

Jeremy Harris

07-12-2010, 04:54 AM

There are a few electric inland waterways boats here in the UK. I hired a Norfolk Broads sailing boat with inboard electric power a few years ago and was impressed. She'd cruise under electric power at around 4kts for maybe 10 to 12 hours before needing a charge, with just a modest array of lead acid batteries down in the keel.

I know of a few diesel electric hybrid boats, including some that use solar panels for augmentation. They work reasonably well and have the major advantage of being able to position the generator anywhere in the boat. One potential problem with the hybrid diesel electric approach is efficiency. Boats aren't like cars, they have a relatively modest peak to average power ratio, average power being maybe 60% to 70% of peak power (cars tend to have a peak to average power ratio of maybe 8:1 or even 10:1, meaning average power might only be 15% of maximum power). This means there isn't a big saving to be had by downsizing the engine on the generator, although it may be enough to make it worthwhile.

There are an increasing number of British canal boat builders looking hard at using hybrid or electric power though, as with more shore power charging points becoming available and environmental concerns bringing pressure to bear on internal combustion engine use people are coming around to the idea that electric power is viable.

Jeremy

pvgenesis

07-12-2010, 02:29 PM

alanrockwood

07-12-2010, 06:03 PM

Hi alanrockwood, it sounds like the usage profile can be succesfully combined with electric propulsion / power management for a good result.
Can you give me an idea of the average size of such a boat?
I also need to know the maximum / cruising power needed to move a boat like this.
A system like this can be combined easily with solar panels and that is the reason we are happy if the boat has large horizontal surfaces available for them.
Keep in mind that the system can be also used for the other electric loads of the boat and this is maybe importand for boats with commercial usage (many electric loads operating for long periods, e.g. TV sets, lighting, air-conditioning, etc.

pvgenesis and Jeremy,

Thanks for the responses.

Concerning sizes and the like, 20x4.4 meter might be considered a typical size. Here is a link to an example. http://www.dutch-barges.net/thomas.html. This particular boat runs roughly 20 to 40 tons, depending on the length.

Speeds are limited on most canals to a few knots, so typical cruising power tends to be rather low. I'll try to look up some typical propulsion power requirements later.

Some boats have a lot of electrical gizzmos on board because a lot of people use them as live-aboard long-term cruisers, so they have washing machines and all sorts of other household appliances. Some people even sell their houses and cruise in their barges full time on the canals of Europe, especially France, but also some of the other heavily canalized (my word) countries.

pvgenesis

07-13-2010, 07:32 AM

Once again, just to remind that I have only a little experience in boat designing.

The size and the weight seem to be just enough for a system like the one I have in mind. Maybe if the internal height could be a bit higher there would be more space for the batteries.
In terms of horizontal surfaces, it looks like there is enough room for 2 – 3kWp of PV panels, mounted in a reversed and wide angled “V” position.
Depending on the season, the geographical position, the actual weather, the shadows by nearby structures and the average daily consumption, this PV power could be enough to cover the daily demand of a typical household consumption.
Of course it is always better to consume less energy by using energy-efficient appliances (led-lighting, energy-class A+ refrigerators / washing machines, gas oven, etc.) and by following the simple and well-known common advices for energy saving.
That way might be possible to achieve a slow battery re-carging while the boat is stationary, although it would be enough success not to use the generator on regular basis.

Concerning the electrical part (this is my part!), supposing you use an electric motor for propulsion, with existing commercial technology it is possible to have a 27kW 3-phase system by combining 9 units inverter / chargers from Outback (in order to use products from your country!). Total cost of about 30000 USD, total weight of about 0.5 tons.
This is enough to drive an AC 3-phase electric motor to produce a mechanical power of more than 30hp. Maybe this is enough to cruise in a speed of a few (5 to 8??) knots.
Of course the maximum engine power can be more than this, e.g. 50hp, but this can only be available with the generator running.
The nominal power of generator must be at least 20% more of the maximum power the vessel will possibly need, e.g 60kVA -3phase.

The transition from battery / inverters mode and slow cruising speed to generator mode and maximum speed can be fully automatic although there will always be a time “gap” of maybe 20 seconds in between. This is probably essential and might arise some safety issues.
The generator will also start / stop automatically in order to recharge the battery bank up to the preset level.

A battery bank of at least 100kWh @ C5 would be necessary for such a system.
Depending on the type of the battery (deep-cycle, marine type at least) this could be a weight of 2.5 to 5 tons and a cost of 15000 to 40000 USD (for a premium long lasting battery).

An amount of 3kWp of PV panels costs something like 8000 – 9000 USD.

I don’t know the cost of the vessel itself but I suppose that a total amount of about 50000 – 70000 for a complete power / energy management and storage system is not too much.
The generator will be in stand-by just for assistance when the boat is stationary.
Note that for a daily consumption of 30kWh (which is a really heavy consumption – almost twice of a typical household) and with no help at all from the PV array (heavy winter clouds), the generator would need only 2 – 3 hours of operation to compensate.
While cruising in low speed (up to 30hp), the generator will run with a duty cycle of about 50% (e.g. 1,5 hours running, 1,5 hour stopped) in order not to discharge the battery deeper than e.g. 50%.

This means that there will be a great saving in generator’s total operating hours. The time saving might be much more than 50% for a boat spending much time stationary!
You can give me an idea of the yearly saving of fuel and maintenance / repairs.

The battery can be discharged in DOD (Depth Of Discharge) up to 80% or even 100% only in emergency situations.
It is a matter of a full case study report to determine exactly all the above sizes but I believe that this is close enough to give you an idea based on real life.
We have already such systems operating in order to electrify small hotels or any other business premises in remote areas.

pvgenesis

07-13-2010, 07:47 AM

…and some additional – probably - important notes and thoughts….

- It would be preferable to use 48V DC electric motors for prupolsion. We would avoid the need of the inverter / charger array and the additional loses they introduce in the system. Only 2 or 3 units for 6 to 9kW would be enough just for the boat’s household loads.
- Depending again on the geographical position where you use your boat, a number of low-noise small wind turbines can also assist the system.
- The system can be fully automated and remotely monitored by experienced people. Manual operation of the generator is always available in case everything else has failed.
- Apart of the main large generator which is absolutely necessary while cruising for more than a couple of hours, maybe a smaller one (e.g. up to 10kVA 1-phase) can be proved more efficient while the boat is stationary. It can also be a low-cost emergency back-up for any reason.
- I believe that it would be very convenient to implement such a system in a boat in designing stage in terms of the available space for the system itself and for the batteries. It is always very difficult to fit a system like this in a boat designed for a diesel engine.

I hope this is helpful for you…

pvgenesis

07-14-2010, 08:55 AM

The transition from battery / inverters mode and slow cruising speed to generator mode and maximum speed can be fully automatic although there will always be a time “gap” of maybe 20 seconds in between. This is probably essential and might arise some safety issues.

Just to clear up this part...
There is no power interruption at all in between. The "gap" of 20 seconds is the delay from the point when the additional power is needed, until the point when the generator is actually connected (by the system) to the loads and the full power is available.
The maximum possible power interruption during this transition can be 20 milliseconds. This is hardly noticable and short enough not to cause any problem to vessel's systems.

gp333

01-16-2011, 11:26 AM

what we can say here? http://www.planetsolar.org/multimedia-photos.en.php

this boat idea I ask on start exist today? after all? ;)

BertKu

01-22-2011, 08:18 AM

what we can say here? http://www.planetsolar.org/multimedia-photos.en.php

this boat idea I ask on start exist today? after all? ;)

Bonna sera, bonjorno , Hold on gp333. Yes, you are right, they exsist, large boats with electro motors. But your question was in thread No 1: 480 Hp i.e. 360 KiloWatt motors. There is in Austraila already a ferry, who is carting automobiles for years across the harbour. Refer battery and new battery technologies. You should have formulated your question differently. Why don't you try it again. But think careful what you like to hear from the forum members. Formulate it in such a way, like : I like to have an electro boat crossing the ocean. Could you give me the parameters to do so. Maybe, you get excactly what you want to hear.
Bert

gp333

01-22-2011, 08:29 AM

BertKu

01-22-2011, 08:43 AM

heh, too risky post again :-))
yes, sure I am not say right parameters good on start. But my question was be how make any solution.. anyone was chance say solution only... but lot wish say that you are 'lunatic' as you ask this at all.

On any way, I am here same person who is ask on start, same person again show link what is one of real solutions. No need ask more. I have idea and solution that solve my question about 30meters electro boat crossing the ocean alone. I am post that others see it only. No need new posts as I know enough now

Excellent gp333. Never must you be worrried when certain characters are being rude and unpleasant. Yes, you could make an electric boat which could cross the ocean. 30 meters, yes, lots of solar panels and only maybe 10 Kw. But you will have to avoid storms, otherwise your power requirements will be maybe 5 to 10 times larger. Your speed would be 8 knots for a displacement hull. But in your case, many members will recommend to make a tri-hull.
Bert

gp333

01-22-2011, 09:25 AM

But you will have to avoid storms, otherwise your power requirements will be maybe 5 to 10 times larger. Your speed would be 8 knots for a displacement hull. But in your case, many members will recommend to make a tri-hull.

yeh, for sure avoid storms.. but in my plans is not so hard required that it be 100% solar and done. Yacht can have diesel generators and in these moments is not problem run diesel to get more power in storm conditions only or similar.

about tri-hull, yes, me looks this as some tri-hull version? as I can see on images, all stay on 2 hulls, but middle 3th hull in very near water. I believe they are design like this.. if it is good condition it go quick as catamaran on "rails", but if harder sea condition that middle hull start be in water and make additional stability