Saturday, June 20, 2009

Re: [Electric Boats] Re: Any larger electric boat owners out there?



Thank you very much! Your site had something on it that I never
thought of before! It solves one of my largest design problems. I
will definitely be giving your guys a change to quote a system for me.
With great strait forward thinking like this, I'm very impressed.

"Voltage: Higher voltage systems are more efficient than lower
voltage systems. However higher voltage systems require additional
safeguards to protect the occupants and are more expensive. The
general rule of thumb is to only use the voltage that you require and
no more.

Battery packs are no greater than 48 volts, or 4 batteries in a string
with a resettable circuit breaker in the positive lead and a battery
switch in the negative lead. Higher voltage systems are configured
with a central high voltage bus located near the controller. For
instance a 72 volt system is configured as two 36 volt battery banks
coming to a central 72 volt bus. A 144 volt system would be 3 48
volt battery banks coming together at a central 144 volt bus. This
architecture limits the exposure to higher voltage on a boat to just
the central bus area. All high voltage wires are limited in
length and require additional protective sheathing.

48 volt systems are easy to work with because of the plentitude of 48
volt equipment available like inverter chargers, solar chargers,
battery chargers and DC to DC converters. " (1)

(1)http://www.propulsionmarine.com/electric_propulsion.htm

Now off to finish reading the rest of you great site!

On Jun 20, 2009, at 3:38 PM, jameslambden wrote:

>
>
> James,
>
> We are currently offering an 18 KW water cooled permanent magnet AC
> drive based on the Perm Motor - see
>
> http://www.propulsionmarine.com/18_kw_e_w_drive.htm
>
> and a 50 KW watercooled permanent magnet brushless AC drive based on
> the UQM motor
>
> http://www.propulsionmarine.com/50_kw_inboard.htm
>
> contact sales@propulsionmarine.com for more information.
>
> James
>
> --- In electricboats@yahoogroups.com, James Sizemore <james@...>
> wrote:
> >
> > I did the numbers on putting in two Solidnav Voyagers, (or similar
> > motors) for a total of 16kw at 600 amps draw. I could supply these
> > motors at half speed indefinitely with power. I have a 7.5kw
> > generator, and my boat can easily hold a 2kw solar array. With this
> > setup I would own the worlds slowest cabin curser. ;-) With around
> > 50 hp?, But I would go.
> >
> > I also did the numbers to kind of come close to replacing the
> > performance I have and I was looking at two motors each in the 60-80
> > kw range. Which depending on the motor efficiency would be around 80
> > hp peak 40 hp or so continuous. To give you an ideal of the amp draw
> > on the batteries at full throttle assuming 100% efficacy for each
> prop:
> > at 48 volts you would need whopping 1250 amps (I have not found a
> > motor in this range)
> > at 144 volts 417 amps (These exist)
> > at 312 volts 192 amp (These exist)
> > Now times the amps by two (one for each prop) for a total of 160 hp.
> > Obviously at that amp draw a third of an hour is all you could do
> with
> > a $12,000 dollar battery pack, say 800 AH at 48 volt at full
> > throttle. Now it might be nice to have this speed for 15 minutes but
> > is it really worth it?
> >
> > Heck I don't know still on the fence. LOL. Option two at low speeds
> > is just as amp efficient as option one, plus you have the option to
> > drain you pack faster if you want, the question is how often would I
> > want to go faster? I'm guess not very often. The down side to option
> > two is as stated below It pretty much forces me into a high voltage
> > battery pack.
> >
> > But if you had a setup in mind, let me know I would be happy to do
> > the numbers! That part is fun. Making a choice and living with it is
> > the hard part. Everything with boats is a trade off....Everything!
> >
> > Feel free to poke fun at my number above if you find flaws.
> >
> >
> >
> > On Jun 20, 2009, at 2:52 AM, Hans Kloepfer wrote:
> >
> > >
> > >
> > > James,
> > >
> > > Not really sure how much power you are looking for on your boat.
> You
> > > have a tall order replacing two big V8's. If you wanted to stay
> with
> > > the simplicity of 48v (which would be alot more convenient) have
> you
> > > considered belting more that one motor to the same shaft? Would
> two
> > > 48v motors per shaft give you the kind of power you are looking
> for?
> > >
> > > --- On Thu, 6/18/09, James Sizemore <james@...> wrote:
> > >
> > > From: James Sizemore <james@...>
> > > Subject: Re: [Electric Boats] Re: Any larger electric boat owners
> > > out there?
> > > To: electricboats@yahoogroups.com
> > > Date: Thursday, June 18, 2009, 2:20 PM
> > >
> > > The first hard choice you have to make is the pack voltage, A 48
> volt
> > >
> > > pack will make buying components for your house solar array easy
> and
> > >
> > > cheap (pretty much standard off-grid setup), and buying a traction
> > >
> > > motor big enough to replace your V8 very hard (I only know of
> one 48
> > >
> > > volt high current low voltage motor and the price scarred the
> paints
> > >
> > > of me). If anyone knows of a large high HP 48 volt motor let me
> > >
> > > know! (The reason they are rare is that high current draw from the
> > >
> > > batteries radically increases the perkert effect, and wire size. )
> > >
> > > But if you go lithium or travel on strait solar/generator (You
> would
> > >
> > > need a big array 1600w minimum to get even a few knots. ) 48 volt
> > >
> > > would be optimal from a simplicity standpoint.
> > >
> > > Or you can go with a 144 volt or 312 volt pack and have lots of
> > >
> > > traction motors choices. But very limited inverter charger choices
> > >
> > > to supply power to the house.
> > >
> > > The DC to DC that I have heard the best gossip on for the high
> voltage
> > >
> > > setup is : http://www.victrone nergy.com/ chargers/ centaur-
> charger-
> > > 12v-24v/
> > >
> > > 90 DCV - 400 DCV input . You will have to go with a grid-tie
> > >
> > > inverter solar cell setup (high voltage solar cells and hight
> voltage
> > >
> > > inverter) They exist but don't have the features of the 48v peers.
> > >
> > > I would prefer the low voltage setup myself ( the the lack of
> motor
> > >
> > > choices is devastating) I have a few high voltage setups on paper
> > >
> > > but nothing I like enough to pull the trigger on yet.
> > >
> > > If you have any question or ideal let me know I have put a lot of
> > >
> > > work into different designs, I'm sure I can save you some time
> looking
> > >
> > > for components.
> > >
> > > On Jun 16, 2009, at 7:08 PM, mcdonaldmike13 wrote:
> > >
> > > >
> > >
> > > >
> > >
> > > > I just found this site today. I too am interested in
> converting my
> > >
> > > > boat to electric. It is a 47 foot river cruiser with a shallow
> draft
> > >
> > > > with a Volvo v8 sterndrive that I would like to remove. We
> plan on
> > >
> > > > using solar and wind for our house power but am getting lost
> on all
> > >
> > > > the electrical options or non-options. This a go slow boat. Are
> > >
> > > > there any viable options out there?
> > >
> > > >
> > >
> > > > --- In electricboats@ yahoogroups. com, James Sizemore <james@>
> > >
> > > > wrote:
> > >
> > > > >
> > >
> > > > > I see a lot of traffic on this list for smaller conversions
> > >
> > > > replacing
> > >
> > > > > A4's and such on 20-30 foot sail boats. Are there any folks
> that
> > >
> > > > have
> > >
> > > > > replaced larger motors on cruisers/trawlers?
> > >
> > > > > I will be replacing two 427 fords (350hp gas engines) on a
> 41 foot
> > >
> > > > > Chris-Craft. This if for a number of reasons including not
> wanting
> > >
> > > > > the ongoing expense of buying gas, second I really hate the
> > >
> > > > monstrous
> > >
> > > > > complexity of combustion engines. I have a computer science/
> > >
> > > > > electrical background so I am much much more knowledgeable and
> > >
> > > > > comfortable with electrical systems. And not to mention the
> smell
> > >
> > > > and
> > >
> > > > > noise of combustion engines. The knowledge I lack right now is
> > > boat
> > >
> > > > > related: prop size pitch ...etc...etc. I don't need the boat
> to
> > >
> > > > plane
> > >
> > > > > at 17 knots or anything like that, although if it does all the
> > >
> > > > better.
> > >
> > > > >
> > >
> > > > > My current thinking is to replace the fords with a pair of
> > > (Netgain
> > >
> > > > > Warp 11'' or Transwarp 11'')'s. The part I can not rap my head
> > >
> > > > > around is if I go direct drive with the Transwarp's will
> they spin
> > >
> > > > the
> > >
> > > > > props to fast? Or should I keep the transmissions that the
> fords
> > > are
> > >
> > > > > bolt to now and go with the Warp's. I would prefer not to
> have the
> > >
> > > > > extra complexity of the transmissions. The Netgains can move a
> > > large
> > >
> > > > > truck at freeway speeds 70+ MPH. My understanding of the
> > >
> > > > conversion of
> > >
> > > > > electrical hp to combustion hp is at 144v these motors
> should be
> > >
> > > > about
> > >
> > > > > the equivalent of a 150-200 hp gas motors with considerable
> more
> > >
> > > > > torque at the low end.
> > >
> > > > >
> > >
> > > > > The boat will soon have a fairly large solar array and
> already has
> > >
> > > > > 7.5 KWH generator. So keeping the battery bank feed should not
> > > be a
> > >
> > > > > problem. I know finding a solar charger/inverter for a 144v
> > > battery
> > >
> > > > > pack will be a real challenge. Any recommendations are
> welcome. I
> > >
> > > > > would also be very curious of other conversions of larger
> plaining
> > >
> > > > > hull boats, and what motors you use and performance you get
> now.
> > >
> > > > Also
> > >
> > > > > any recommendations on motors/charges/ controllers or kits for
> > > boats
> > >
> > > > > this size would be most welcome.
> > >
> > > > >
> > >
> > > > >
> > >
> > > > >
> > >
> > > > >
> > >
> > > > > [Non-text portions of this message have been removed]
> > >
> > > > >
> > >
> > > >
> > >
> > > >
> > >
> > > >
> > >
> > > [Non-text portions of this message have been removed]
> > >
> > >
> > >
> > >
> > >
> > >
> > >
> > >
> > >
> > >
> > >
> > > [Non-text portions of this message have been removed]
> > >
> > >
> > >
> >
> >
> >
> > [Non-text portions of this message have been removed]
> >
>
>
>

[Non-text portions of this message have been removed]

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