Re: A question about Solar power
Dan,
To give an idea of the power requirements for even a modest electric boat...
Yesterday we had out my Endura 30 powered Windsprint to try with a new pair of group 31,
115 a/h batts. Not supposed to mix up things too much in scientific experimentation, but
also had a new Kipawa prop.
http://www.kipawapropellers.com
Total weight was over 650 pounds on a 12 - 14' waterline. At slack water no wind, the chip
log showed about 3 mph full bore, or about 30 amps draw; 2 mph at half speed ahead, which
with the resistors I imagine draws something short of 20 amps.
4 hours running, mostly on settings 3 and 4, discharged the batteries 50%.
I'm convinced (again!) that the only way to go far except in the mildest conditions with
the Endura 30 is to run at full speed. But even those batteries would have been down to
nothing in <6 hours at 30 amps -and not very nice to them.
It was sunny the entire time -except where we were pulled up to a shady bank. Speculating,
say we used 115 a/h. A solar array that good looks on the order of about 120 square feet.
( If one 30 a/h a 12 hour day panel needs 10 sq. ft, then a dozen of them yields the power
we used in 4 hours)
The prop seemed a wash, though some more experimentation is in order. For now I could only
verify a larger wake and that the material is somewhat softer than the stock material. The
edge roughed up a bit without very much encouragement.
BTW A wonderful time was had by all. We went back about 5 miles off the main channel up a
slough to a little lake and back. Could not help noticing the other 5 gas outboard powered
craft that zipped by at high speed, stayed 5 minutes and turned around while we took all
day to drink the whole thing in.
Musing on a MinKot Maxxum 1hp with the pwm controller but I'd still be chicken for all but
the softest water; unless maybe in a converted 24' 3 Man Light Dory on about the same weight.
Mark
Dan Burrill wrote:
To give an idea of the power requirements for even a modest electric boat...
Yesterday we had out my Endura 30 powered Windsprint to try with a new pair of group 31,
115 a/h batts. Not supposed to mix up things too much in scientific experimentation, but
also had a new Kipawa prop.
http://www.kipawapropellers.com
Total weight was over 650 pounds on a 12 - 14' waterline. At slack water no wind, the chip
log showed about 3 mph full bore, or about 30 amps draw; 2 mph at half speed ahead, which
with the resistors I imagine draws something short of 20 amps.
4 hours running, mostly on settings 3 and 4, discharged the batteries 50%.
I'm convinced (again!) that the only way to go far except in the mildest conditions with
the Endura 30 is to run at full speed. But even those batteries would have been down to
nothing in <6 hours at 30 amps -and not very nice to them.
It was sunny the entire time -except where we were pulled up to a shady bank. Speculating,
say we used 115 a/h. A solar array that good looks on the order of about 120 square feet.
( If one 30 a/h a 12 hour day panel needs 10 sq. ft, then a dozen of them yields the power
we used in 4 hours)
The prop seemed a wash, though some more experimentation is in order. For now I could only
verify a larger wake and that the material is somewhat softer than the stock material. The
edge roughed up a bit without very much encouragement.
BTW A wonderful time was had by all. We went back about 5 miles off the main channel up a
slough to a little lake and back. Could not help noticing the other 5 gas outboard powered
craft that zipped by at high speed, stayed 5 minutes and turned around while we took all
day to drink the whole thing in.
Musing on a MinKot Maxxum 1hp with the pwm controller but I'd still be chicken for all but
the softest water; unless maybe in a converted 24' 3 Man Light Dory on about the same weight.
Mark
Dan Burrill wrote:
>
> > Is there anyone here that uses solar panels to power his boat. I have
> > a small boat and have been toying with the idea of running the
> > electric motor on a solar panel. I might even decide to build another
> > boat if the solar thing works good. I was wondering how much it
> > costs, and how many watts, volts, amps or whatever i would need to
> > run the motor efficiently.
>
> Sorry I can't help directly, the only solar-powered boat I've seen is Ra
> - an aluminium catamaran used for site seeing trips on Barton Broad in
> Norfolk. A brief description and picture (though not a very good one)
> can be found here:
>
>http://www.waterscape.com/servicesdirectory/Solar_Boat_Ra
>
> From what I've read on the subject myself it's possible, but you really
> need to be thinking in terms of using solar power to charge a battery
> and using the battery to power the boat (be a bit annoying to lose your
> engine every time a cloud goes in front of the sun). This adds to both
> cost and weight, as not only do you need the battery and a decent-sized
> set of solar panels, you also need all of the associated kit to regulate
> the charging and discharging of the batteries.
>
> anyway, I hope at least some of that is useful
>
> Dan
It probably wouldn't be the huge increase one gets with an automobile.
Running at a constant speed is very efficient for an infernal combustion
engine. It's the starting and stopping that pours out the fuel. The
battery is acting as an accumulator, but boats are more usually constant
speed applications and every time you change the energy form you lose a
bunch. (chemical to mechanical to electrical to mechanical to fluidic)
Watch yourself when playing with high (120 vac) voltages in a marine
environment.
Roger
derbyrm@...
http://home.earthlink.net/~derbyrm
Running at a constant speed is very efficient for an infernal combustion
engine. It's the starting and stopping that pours out the fuel. The
battery is acting as an accumulator, but boats are more usually constant
speed applications and every time you change the energy form you lose a
bunch. (chemical to mechanical to electrical to mechanical to fluidic)
Watch yourself when playing with high (120 vac) voltages in a marine
environment.
Roger
derbyrm@...
http://home.earthlink.net/~derbyrm
----- Original Message -----
From: "arrrrrmatee" <arrrrrmatee@...>
> I've thought about that also. I don't see why it wouldn't work.
> I'd be very curious to know how many miles to the gallon
> you'd be able to get with the generator. I was even thinking
> about making an inboard motor out of an electric shop motor.
>
> Jim
>
> --- Inbolger@yahoogroups.com, James Greene <jg6892@g...> wrote:
>> Would it be possible to replace the solar panels and batteries with
>> one of those tiny little generators? I'm thinking about the kind that
>> come with a handle so you can carry them around like a suitcase or
>> toolbox. I think the smallest is 650 or 750 watts if I'm not mistaken.
>>
>> Would this produce enough power for your 30 lb thrust trolling
>> motor?
>>
>> If so, you would end up with a generator that you can use for other
>> things when it's not being used in your boat, and the cost might
>> even be less than the combined expense for the solar panels and battery.
>>
>> Of course you'll hear the generator running, so if you're trying to
>> avoid the noise this won't be the solution for you. But if you're
>> thinking about a solution that might cost less or give you other
>> uses for the equipment you have to buy, this might just be a better
>> solution -- assuming that one of these little generators can produce
>> enough power.
>>
>> James Greene
>>
>> On Aug 25, 2005, at 09:54, gbship wrote:
>> > Here's some recent experience that may help. I have a Michalak
>> > Frolic2 design and just a few days ago experimented with an
>> > electric trolling motor. With a 30-pound thrust motor, the boat
>> > would do 3-3.1 knots (and probably a bit better if the trim had
>> > been better) at full thrust, and about 2 to 2.2 with it set down
>> > one notch (it has five forward speeds).
>> > My recollection is motors in the 30-36 lb thrust range use about
> 30
>> > amps/hour of juice -- someone else probably has a better handle
> on that
>> > than my spotty memory. Since you shouldn't run a battery down
> more than
>> > 50 percent, that means an hour or so with the typical 75 amp hour
>> > battery, or about 30 minutes at full speed with the 31 amp hour
> battery
>> > on the Frolic. Cutting back speed greatly increases the range and
>> > lowers usage, but I don't have the figures. Right now in storage
> I have
>> > a 50 watt solar panel, which means at peak sun it puts out 3 amps
> or a
>> > little bit better. Sorry, don't have the dimension handy, but
> it's some
>> > like two by three or four feet. It would be possible to fit five
> or six
>> > of these on Frolic (leaving the sailing rig ashore) which means I
> would
>> > running it at half throttle or better in full sunlight. Now if I
> put a
>> > hart bimini over the cockpit, I might get 10 panels on, but that
> would
>> > be extra weight and windage, which would imply a bigger motor and
> the
>> > eneed for more cells . . . . Now if I had a 75 amp battery on as
> well
>> > as the five or six cells, what I'd have is nearly unlimitied time
> at
>> > half to 3/4 throttle, and much expanded time at full throttle.
> After an
>> > hour of running at full throttle, you would have used 30 amps,
> but the
>> > panels would have replaced 15 to 18 amps of that. If you ran for
> an
>> > hour and then stopped for a half an hour to swim or beachcomb,
> your
>> > battery would be fully charged again. If you ran it downt o 50
> percent,
>> > you'd have it charged in a couple houses. Assuming those sudden
> S. Fla.
>> > thunderstorms don't come up and steal your sun!
>> >
>> > Gary Blankenship
>> >
>> > P.S. If you're thinking about using an off the shelf trolling
> motor,
>> > check carefully first.One manufacturer told me their motors
> weren't
>> > made to run at full speed for extended periods.
>> >
>> > --- Inbolger@yahoogroups.com, "arrrrrmatee" <arrrrrmatee@y...>
> wrote:
>> >> Is there anyone here that uses solar panels to power his boat. I
> have
>> >> a small boat and have been toying with the idea of running the
>> >> electric motor on a solar panel. I might even decide to build
> another
>> >> boat if the solar thing works good. I was wondering how much it
>> >> costs, and how many watts, volts, amps or whatever i would need
> to
>> >> run the motor efficiently.
>> >>
>> >> Jim
>> >> S. Fla
>> >
>> >
>> >
>> >
>> >
>> > Bolger rules!!!
>> > - no cursing, flaming, trolling, spamming, or flogging dead horses
>> > - stay on topic, stay on thread, punctuate, no 'Ed, thanks, Fred'
> posts
>> > - Pls add your comments at the TOP, SIGN your posts, and snip away
>> > - Plans: Mr. Philip C. Bolger, P.O. Box 1209, Gloucester, MA,
> 01930,
>> > Fax: (978) 282-1349
>> > - Unsubscribe:bolger-unsubscribe@yahoogroups.com
>> > - Open discussion:bolger_coffee_lounge-subscribe@yahoogroups.com
>> > Yahoo! Groups Links
>> >
>> >
>> >
>> >
>> >
>> >
>> >
>> >
>
>
>
>
>
> Bolger rules!!!
> - no cursing, flaming, trolling, spamming, or flogging dead horses
> - stay on topic, stay on thread, punctuate, no 'Ed, thanks, Fred' posts
> - Pls add your comments at the TOP, SIGN your posts, and snip away
> - Plans: Mr. Philip C. Bolger, P.O. Box 1209, Gloucester, MA, 01930, Fax:
> (978) 282-1349
> - Unsubscribe:bolger-unsubscribe@yahoogroups.com
> - Open discussion:bolger_coffee_lounge-subscribe@yahoogroups.com
> Yahoo! Groups Links
>
>
>
>
>
>
>
I've thought about that also. I don't see why it wouldn't work. I'd
be very curious to know how many miles to the gallon you'd be able to
get with the generator. I was even thinking about making an inboard
motor out of an electric shop motor.
Jim
be very curious to know how many miles to the gallon you'd be able to
get with the generator. I was even thinking about making an inboard
motor out of an electric shop motor.
Jim
--- Inbolger@yahoogroups.com, James Greene <jg6892@g...> wrote:
> Would it be possible to replace the solar panels and batteries with
one
> of those tiny little generators? I'm thinking about the kind that
come
> with a handle so you can carry them around like a suitcase or
toolbox.
> I think the smallest is 650 or 750 watts if I'm not mistaken.
>
> Would this produce enough power for your 30 lb thrust trolling
motor?
>
> If so, you would end up with a generator that you can use for other
> things when it's not being used in your boat, and the cost might
even
> be less than the combined expense for the solar panels and battery.
>
> Of course you'll hear the generator running, so if you're trying to
> avoid the noise this won't be the solution for you. But if you're
> thinking about a solution that might cost less or give you other
uses
> for the equipment you have to buy, this might just be a better
solution
> -- assuming that one of these little generators can produce enough
> power.
>
> James Greene
>
>
>
>
>
> On Aug 25, 2005, at 09:54, gbship wrote:
>
> > Jim:
> >
> > Here's some recent experience that may help. I have a Michalak
Frolic2
> > design and just a few days ago experimented with an electric
trolling
> > motor. With a 30-pound thrust motor, the boat would do 3-3.1
knots (and
> > probably a bit better if the trim had been better) at full
thrust, and
> > about 2 to 2.2 with it set down one notch (it has five forward
speeds).
> > My recollection is motors in the 30-36 lb thrust range use about
30
> > amps/hour of juice -- someone else probably has a better handle
on that
> > than my spotty memory. Since you shouldn't run a battery down
more than
> > 50 percent, that means an hour or so with the typical 75 amp hour
> > battery, or about 30 minutes at full speed with the 31 amp hour
battery
> > on the Frolic. Cutting back speed greatly increases the range and
> > lowers usage, but I don't have the figures. Right now in storage
I have
> > a 50 watt solar panel, which means at peak sun it puts out 3 amps
or a
> > little bit better. Sorry, don't have the dimension handy, but
it's some
> > like two by three or four feet. It would be possible to fit five
or six
> > of these on Frolic (leaving the sailing rig ashore) which means I
would
> > running it at half throttle or better in full sunlight. Now if I
put a
> > hart bimini over the cockpit, I might get 10 panels on, but that
would
> > be extra weight and windage, which would imply a bigger motor and
the
> > eneed for more cells . . . . Now if I had a 75 amp battery on as
well
> > as the five or six cells, what I'd have is nearly unlimitied time
at
> > half to 3/4 throttle, and much expanded time at full throttle.
After an
> > hour of running at full throttle, you would have used 30 amps,
but the
> > panels would have replaced 15 to 18 amps of that. If you ran for
an
> > hour and then stopped for a half an hour to swim or beachcomb,
your
> > battery would be fully charged again. If you ran it downt o 50
percent,
> > you'd have it charged in a couple houses. Assuming those sudden
S. Fla.
> > thunderstorms don't come up and steal your sun!
> >
> > Gary Blankenship
> >
> > P.S. If you're thinking about using an off the shelf trolling
motor,
> > check carefully first.One manufacturer told me their motors
weren't
> > made to run at full speed for extended periods.
> >
> > --- Inbolger@yahoogroups.com, "arrrrrmatee" <arrrrrmatee@y...>
wrote:
> >> Is there anyone here that uses solar panels to power his boat. I
have
> >> a small boat and have been toying with the idea of running the
> >> electric motor on a solar panel. I might even decide to build
another
> >> boat if the solar thing works good. I was wondering how much it
> >> costs, and how many watts, volts, amps or whatever i would need
to
> >> run the motor efficiently.
> >>
> >> Jim
> >> S. Fla
> >
> >
> >
> >
> >
> > Bolger rules!!!
> > - no cursing, flaming, trolling, spamming, or flogging dead horses
> > - stay on topic, stay on thread, punctuate, no 'Ed, thanks, Fred'
posts
> > - Pls add your comments at the TOP, SIGN your posts, and snip away
> > - Plans: Mr. Philip C. Bolger, P.O. Box 1209, Gloucester, MA,
01930,
> > Fax: (978) 282-1349
> > - Unsubscribe:bolger-unsubscribe@yahoogroups.com
> > - Open discussion:bolger_coffee_lounge-subscribe@yahoogroups.com
> > Yahoo! Groups Links
> >
> >
> >
> >
> >
> >
> >
> >
Seehttp://www.gosolar.com/3rdwave/for a nice solar powered Rhodes 19 hull.
The article gives full specs. - Bill
_____
From:bolger@yahoogroups.com[mailto:bolger@yahoogroups.com] On Behalf Of
oarmandt
Sent: Thursday, August 25, 2005 8:34 PM
To:bolger@yahoogroups.com
Subject: [bolger] Re: A question about Solar power
The article gives full specs. - Bill
_____
From:bolger@yahoogroups.com[mailto:bolger@yahoogroups.com] On Behalf Of
oarmandt
Sent: Thursday, August 25, 2005 8:34 PM
To:bolger@yahoogroups.com
Subject: [bolger] Re: A question about Solar power
--- Inbolger@yahoogroups.com, "gbship" <gbship@c...> wrote:
>..... Right now in storage I have
> a 50 watt solar panel, which means at peak sun it puts out 3 amps or a
> little bit better. ....
I'll bet that the 50 watt rating is at high noon, at low latitude, on
a crystal clear day. Of course, it will have to be oriented square to
the incident sunlight as well. Might be tough to do if it is rigidly
fixed to your cabin top. Take reduction factors for all deviations
from the above, plus dirt on the surface, and you get a pitifully low
percentage of rated output. Better rig several times the theoretical
number of panels.
Doug
Bolger rules!!!
- no cursing, flaming, trolling, spamming, or flogging dead horses
- stay on topic, stay on thread, punctuate, no 'Ed, thanks, Fred' posts
- Pls add your comments at the TOP, SIGN your posts, and snip away
- Plans: Mr. Philip C. Bolger, P.O. Box 1209, Gloucester, MA, 01930, Fax:
(978) 282-1349
- Unsubscribe:bolger-unsubscribe@yahoogroups.com
- Open discussion:bolger_coffee_lounge-subscribe@yahoogroups.com
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--- Inbolger@yahoogroups.com, "gbship" <gbship@c...> wrote:
a crystal clear day. Of course, it will have to be oriented square to
the incident sunlight as well. Might be tough to do if it is rigidly
fixed to your cabin top. Take reduction factors for all deviations
from the above, plus dirt on the surface, and you get a pitifully low
percentage of rated output. Better rig several times the theoretical
number of panels.
Doug
>..... Right now in storage I haveI'll bet that the 50 watt rating is at high noon, at low latitude, on
> a 50 watt solar panel, which means at peak sun it puts out 3 amps or a
> little bit better. ....
a crystal clear day. Of course, it will have to be oriented square to
the incident sunlight as well. Might be tough to do if it is rigidly
fixed to your cabin top. Take reduction factors for all deviations
from the above, plus dirt on the surface, and you get a pitifully low
percentage of rated output. Better rig several times the theoretical
number of panels.
Doug
Would it be possible to replace the solar panels and batteries with one
of those tiny little generators? I'm thinking about the kind that come
with a handle so you can carry them around like a suitcase or toolbox.
I think the smallest is 650 or 750 watts if I'm not mistaken.
Would this produce enough power for your 30 lb thrust trolling motor?
If so, you would end up with a generator that you can use for other
things when it's not being used in your boat, and the cost might even
be less than the combined expense for the solar panels and battery.
Of course you'll hear the generator running, so if you're trying to
avoid the noise this won't be the solution for you. But if you're
thinking about a solution that might cost less or give you other uses
for the equipment you have to buy, this might just be a better solution
-- assuming that one of these little generators can produce enough
power.
James Greene
of those tiny little generators? I'm thinking about the kind that come
with a handle so you can carry them around like a suitcase or toolbox.
I think the smallest is 650 or 750 watts if I'm not mistaken.
Would this produce enough power for your 30 lb thrust trolling motor?
If so, you would end up with a generator that you can use for other
things when it's not being used in your boat, and the cost might even
be less than the combined expense for the solar panels and battery.
Of course you'll hear the generator running, so if you're trying to
avoid the noise this won't be the solution for you. But if you're
thinking about a solution that might cost less or give you other uses
for the equipment you have to buy, this might just be a better solution
-- assuming that one of these little generators can produce enough
power.
James Greene
On Aug 25, 2005, at 09:54, gbship wrote:
> Jim:
>
> Here's some recent experience that may help. I have a Michalak Frolic2
> design and just a few days ago experimented with an electric trolling
> motor. With a 30-pound thrust motor, the boat would do 3-3.1 knots (and
> probably a bit better if the trim had been better) at full thrust, and
> about 2 to 2.2 with it set down one notch (it has five forward speeds).
> My recollection is motors in the 30-36 lb thrust range use about 30
> amps/hour of juice -- someone else probably has a better handle on that
> than my spotty memory. Since you shouldn't run a battery down more than
> 50 percent, that means an hour or so with the typical 75 amp hour
> battery, or about 30 minutes at full speed with the 31 amp hour battery
> on the Frolic. Cutting back speed greatly increases the range and
> lowers usage, but I don't have the figures. Right now in storage I have
> a 50 watt solar panel, which means at peak sun it puts out 3 amps or a
> little bit better. Sorry, don't have the dimension handy, but it's some
> like two by three or four feet. It would be possible to fit five or six
> of these on Frolic (leaving the sailing rig ashore) which means I would
> running it at half throttle or better in full sunlight. Now if I put a
> hart bimini over the cockpit, I might get 10 panels on, but that would
> be extra weight and windage, which would imply a bigger motor and the
> eneed for more cells . . . . Now if I had a 75 amp battery on as well
> as the five or six cells, what I'd have is nearly unlimitied time at
> half to 3/4 throttle, and much expanded time at full throttle. After an
> hour of running at full throttle, you would have used 30 amps, but the
> panels would have replaced 15 to 18 amps of that. If you ran for an
> hour and then stopped for a half an hour to swim or beachcomb, your
> battery would be fully charged again. If you ran it downt o 50 percent,
> you'd have it charged in a couple houses. Assuming those sudden S. Fla.
> thunderstorms don't come up and steal your sun!
>
> Gary Blankenship
>
> P.S. If you're thinking about using an off the shelf trolling motor,
> check carefully first.One manufacturer told me their motors weren't
> made to run at full speed for extended periods.
>
> --- Inbolger@yahoogroups.com, "arrrrrmatee" <arrrrrmatee@y...> wrote:
>> Is there anyone here that uses solar panels to power his boat. I have
>> a small boat and have been toying with the idea of running the
>> electric motor on a solar panel. I might even decide to build another
>> boat if the solar thing works good. I was wondering how much it
>> costs, and how many watts, volts, amps or whatever i would need to
>> run the motor efficiently.
>>
>> Jim
>> S. Fla
>
>
>
>
>
> Bolger rules!!!
> - no cursing, flaming, trolling, spamming, or flogging dead horses
> - stay on topic, stay on thread, punctuate, no 'Ed, thanks, Fred' posts
> - Pls add your comments at the TOP, SIGN your posts, and snip away
> - Plans: Mr. Philip C. Bolger, P.O. Box 1209, Gloucester, MA, 01930,
> Fax: (978) 282-1349
> - Unsubscribe:bolger-unsubscribe@yahoogroups.com
> - Open discussion:bolger_coffee_lounge-subscribe@yahoogroups.com
> Yahoo! Groups Links
>
>
>
>
>
>
>
>
A 30 lb. thrust trolling motor at full throttle draws closer to 40 amps,
not directly measured with an ammeter, but based on time run and charge
used. Another important consideration is the mechanism used by your
motor and/or controller to "throttle down". I have a 30 lb. thrust Minn
Kota of their Endura line. My understanding (haven't taken it apart,
tempting though that is) is these use resistance in series with the
power switch, generating heat and significant efficiency loss at less
than full "throttle". Pulse width modulation is a much more efficient
control scheme. Short bursts of full power are delivered (pulses) at
varying intervals to vary the power output of the motor. Theoretically
no extra heat loss above and beyond that inherent in the motor
windings. The same technology is available in stand alone controllers,
battery power in, motor power out. I personally have never used a PWM
motor or controller, but everything I've read and been told is that in
practice, it does make a huge difference in battery life when used at
less than full power. I, too, am toying with the idea of an all
electric boat, probably "cheating" with a generator as the energy
density of batteries just isn't high enough to be practical for decent
range. If I go that route, I wouldn't consider not using PWM, at least
based on my as yet developing knowledge on the subject.
gbship wrote:
not directly measured with an ammeter, but based on time run and charge
used. Another important consideration is the mechanism used by your
motor and/or controller to "throttle down". I have a 30 lb. thrust Minn
Kota of their Endura line. My understanding (haven't taken it apart,
tempting though that is) is these use resistance in series with the
power switch, generating heat and significant efficiency loss at less
than full "throttle". Pulse width modulation is a much more efficient
control scheme. Short bursts of full power are delivered (pulses) at
varying intervals to vary the power output of the motor. Theoretically
no extra heat loss above and beyond that inherent in the motor
windings. The same technology is available in stand alone controllers,
battery power in, motor power out. I personally have never used a PWM
motor or controller, but everything I've read and been told is that in
practice, it does make a huge difference in battery life when used at
less than full power. I, too, am toying with the idea of an all
electric boat, probably "cheating" with a generator as the energy
density of batteries just isn't high enough to be practical for decent
range. If I go that route, I wouldn't consider not using PWM, at least
based on my as yet developing knowledge on the subject.
gbship wrote:
>Jim:
>
>Here's some recent experience that may help. I have a Michalak Frolic2
>design and just a few days ago experimented with an electric trolling
>motor. With a 30-pound thrust motor, the boat would do 3-3.1 knots (and
>probably a bit better if the trim had been better) at full thrust, and
>about 2 to 2.2 with it set down one notch (it has five forward speeds).
>My recollection is motors in the 30-36 lb thrust range use about 30
>amps/hour of juice -- someone else probably has a better handle on that
>than my spotty memory. Since you shouldn't run a battery down more than
>50 percent, that means an hour or so with the typical 75 amp hour
>battery, or about 30 minutes at full speed with the 31 amp hour battery
>on the Frolic. Cutting back speed greatly increases the range and
>lowers usage, but I don't have the figures. Right now in storage I have
>a 50 watt solar panel, which means at peak sun it puts out 3 amps or a
>little bit better. Sorry, don't have the dimension handy, but it's some
>like two by three or four feet. It would be possible to fit five or six
>of these on Frolic (leaving the sailing rig ashore) which means I would
>running it at half throttle or better in full sunlight. Now if I put a
>hart bimini over the cockpit, I might get 10 panels on, but that would
>be extra weight and windage, which would imply a bigger motor and the
>eneed for more cells . . . . Now if I had a 75 amp battery on as well
>as the five or six cells, what I'd have is nearly unlimitied time at
>half to 3/4 throttle, and much expanded time at full throttle. After an
>hour of running at full throttle, you would have used 30 amps, but the
>panels would have replaced 15 to 18 amps of that. If you ran for an
>hour and then stopped for a half an hour to swim or beachcomb, your
>battery would be fully charged again. If you ran it downt o 50 percent,
>you'd have it charged in a couple houses. Assuming those sudden S. Fla.
>thunderstorms don't come up and steal your sun!
>
>Gary Blankenship
>
>P.S. If you're thinking about using an off the shelf trolling motor,
>check carefully first.One manufacturer told me their motors weren't
>made to run at full speed for extended periods.
>
>--- Inbolger@yahoogroups.com, "arrrrrmatee" <arrrrrmatee@y...> wrote:
>
>
>>Is there anyone here that uses solar panels to power his boat. I have
>>a small boat and have been toying with the idea of running the
>>electric motor on a solar panel. I might even decide to build another
>>boat if the solar thing works good. I was wondering how much it
>>costs, and how many watts, volts, amps or whatever i would need to
>>run the motor efficiently.
>>
>>Jim
>>S. Fla
>>
>>
>
>
>
>
>
>Bolger rules!!!
>- no cursing, flaming, trolling, spamming, or flogging dead horses
>- stay on topic, stay on thread, punctuate, no 'Ed, thanks, Fred' posts
>- Pls add your comments at the TOP, SIGN your posts, and snip away
>- Plans: Mr. Philip C. Bolger, P.O. Box 1209, Gloucester, MA, 01930, Fax: (978) 282-1349
>- Unsubscribe:bolger-unsubscribe@yahoogroups.com
>- Open discussion:bolger_coffee_lounge-subscribe@yahoogroups.com
>Yahoo! Groups Links
>
>
>
>
>
>
>
>
>
Jim:
Here's some recent experience that may help. I have a Michalak Frolic2
design and just a few days ago experimented with an electric trolling
motor. With a 30-pound thrust motor, the boat would do 3-3.1 knots (and
probably a bit better if the trim had been better) at full thrust, and
about 2 to 2.2 with it set down one notch (it has five forward speeds).
My recollection is motors in the 30-36 lb thrust range use about 30
amps/hour of juice -- someone else probably has a better handle on that
than my spotty memory. Since you shouldn't run a battery down more than
50 percent, that means an hour or so with the typical 75 amp hour
battery, or about 30 minutes at full speed with the 31 amp hour battery
on the Frolic. Cutting back speed greatly increases the range and
lowers usage, but I don't have the figures. Right now in storage I have
a 50 watt solar panel, which means at peak sun it puts out 3 amps or a
little bit better. Sorry, don't have the dimension handy, but it's some
like two by three or four feet. It would be possible to fit five or six
of these on Frolic (leaving the sailing rig ashore) which means I would
running it at half throttle or better in full sunlight. Now if I put a
hart bimini over the cockpit, I might get 10 panels on, but that would
be extra weight and windage, which would imply a bigger motor and the
eneed for more cells . . . . Now if I had a 75 amp battery on as well
as the five or six cells, what I'd have is nearly unlimitied time at
half to 3/4 throttle, and much expanded time at full throttle. After an
hour of running at full throttle, you would have used 30 amps, but the
panels would have replaced 15 to 18 amps of that. If you ran for an
hour and then stopped for a half an hour to swim or beachcomb, your
battery would be fully charged again. If you ran it downt o 50 percent,
you'd have it charged in a couple houses. Assuming those sudden S. Fla.
thunderstorms don't come up and steal your sun!
Gary Blankenship
P.S. If you're thinking about using an off the shelf trolling motor,
check carefully first.One manufacturer told me their motors weren't
made to run at full speed for extended periods.
Here's some recent experience that may help. I have a Michalak Frolic2
design and just a few days ago experimented with an electric trolling
motor. With a 30-pound thrust motor, the boat would do 3-3.1 knots (and
probably a bit better if the trim had been better) at full thrust, and
about 2 to 2.2 with it set down one notch (it has five forward speeds).
My recollection is motors in the 30-36 lb thrust range use about 30
amps/hour of juice -- someone else probably has a better handle on that
than my spotty memory. Since you shouldn't run a battery down more than
50 percent, that means an hour or so with the typical 75 amp hour
battery, or about 30 minutes at full speed with the 31 amp hour battery
on the Frolic. Cutting back speed greatly increases the range and
lowers usage, but I don't have the figures. Right now in storage I have
a 50 watt solar panel, which means at peak sun it puts out 3 amps or a
little bit better. Sorry, don't have the dimension handy, but it's some
like two by three or four feet. It would be possible to fit five or six
of these on Frolic (leaving the sailing rig ashore) which means I would
running it at half throttle or better in full sunlight. Now if I put a
hart bimini over the cockpit, I might get 10 panels on, but that would
be extra weight and windage, which would imply a bigger motor and the
eneed for more cells . . . . Now if I had a 75 amp battery on as well
as the five or six cells, what I'd have is nearly unlimitied time at
half to 3/4 throttle, and much expanded time at full throttle. After an
hour of running at full throttle, you would have used 30 amps, but the
panels would have replaced 15 to 18 amps of that. If you ran for an
hour and then stopped for a half an hour to swim or beachcomb, your
battery would be fully charged again. If you ran it downt o 50 percent,
you'd have it charged in a couple houses. Assuming those sudden S. Fla.
thunderstorms don't come up and steal your sun!
Gary Blankenship
P.S. If you're thinking about using an off the shelf trolling motor,
check carefully first.One manufacturer told me their motors weren't
made to run at full speed for extended periods.
--- Inbolger@yahoogroups.com, "arrrrrmatee" <arrrrrmatee@y...> wrote:
> Is there anyone here that uses solar panels to power his boat. I have
> a small boat and have been toying with the idea of running the
> electric motor on a solar panel. I might even decide to build another
> boat if the solar thing works good. I was wondering how much it
> costs, and how many watts, volts, amps or whatever i would need to
> run the motor efficiently.
>
> Jim
> S. Fla
> Is there anyone here that uses solar panels to power his boat. I haveSorry I can't help directly, the only solar-powered boat I've seen is Ra
> a small boat and have been toying with the idea of running the
> electric motor on a solar panel. I might even decide to build another
> boat if the solar thing works good. I was wondering how much it
> costs, and how many watts, volts, amps or whatever i would need to
> run the motor efficiently.
- an aluminium catamaran used for site seeing trips on Barton Broad in
Norfolk. A brief description and picture (though not a very good one)
can be found here:
http://www.waterscape.com/servicesdirectory/Solar_Boat_Ra
From what I've read on the subject myself it's possible, but you really
need to be thinking in terms of using solar power to charge a battery
and using the battery to power the boat (be a bit annoying to lose your
engine every time a cloud goes in front of the sun). This adds to both
cost and weight, as not only do you need the battery and a decent-sized
set of solar panels, you also need all of the associated kit to regulate
the charging and discharging of the batteries.
anyway, I hope at least some of that is useful
Dan
Get a copy of "Electric Propulsion for Boats" by Charles Mathys
available from Amazon.com It discusses his successful efforts in this
area in great detail. Also detailed discussion of motors and
controllers.
available from Amazon.com It discusses his successful efforts in this
area in great detail. Also detailed discussion of motors and
controllers.
--- Inbolger@yahoogroups.com, "arrrrrmatee" <arrrrrmatee@y...> wrote:
> Is there anyone here that uses solar panels to power his boat. I
have
> a small boat and have been toying with the idea of running the
> electric motor on a solar panel. I might even decide to build
another
> boat if the solar thing works good. I was wondering how much it
> costs, and how many watts, volts, amps or whatever i would need to
> run the motor efficiently.
>
> Jim
> S. Fla
Hi Jim,
There's a great article in the July August issue of
WoodenBoat magazine about a solar-powered boat in
Australia. Well worth a read to give you some idea of
the problems of solar-powered boats and the solutions
that have been found.
Bill Samson
___________________________________________________________
How much free photo storage do you get? Store your holiday
snaps for FREE with Yahoo! Photoshttp://uk.photos.yahoo.com
There's a great article in the July August issue of
WoodenBoat magazine about a solar-powered boat in
Australia. Well worth a read to give you some idea of
the problems of solar-powered boats and the solutions
that have been found.
Bill Samson
___________________________________________________________
How much free photo storage do you get? Store your holiday
snaps for FREE with Yahoo! Photoshttp://uk.photos.yahoo.com
Is there anyone here that uses solar panels to power his boat. I have
a small boat and have been toying with the idea of running the
electric motor on a solar panel. I might even decide to build another
boat if the solar thing works good. I was wondering how much it
costs, and how many watts, volts, amps or whatever i would need to
run the motor efficiently.
Jim
S. Fla
a small boat and have been toying with the idea of running the
electric motor on a solar panel. I might even decide to build another
boat if the solar thing works good. I was wondering how much it
costs, and how many watts, volts, amps or whatever i would need to
run the motor efficiently.
Jim
S. Fla
look into the last issue of wooden boat, thay had a beautifull electric / solar boat from Australia.
Scott
Scott
----- Original Message -----
From: Dan Burrill
To:bolger@yahoogroups.com
Sent: Thursday, August 25, 2005 4:30 AM
Subject: Re: [bolger] A question about Solar power
> Is there anyone here that uses solar panels to power his boat. I have
> a small boat and have been toying with the idea of running the
> electric motor on a solar panel. I might even decide to build another
> boat if the solar thing works good. I was wondering how much it
> costs, and how many watts, volts, amps or whatever i would need to
> run the motor efficiently.
Sorry I can't help directly, the only solar-powered boat I've seen is Ra
- an aluminium catamaran used for site seeing trips on Barton Broad in
Norfolk. A brief description and picture (though not a very good one)
can be found here:
http://www.waterscape.com/servicesdirectory/Solar_Boat_Ra
From what I've read on the subject myself it's possible, but you really
need to be thinking in terms of using solar power to charge a battery
and using the battery to power the boat (be a bit annoying to lose your
engine every time a cloud goes in front of the sun). This adds to both
cost and weight, as not only do you need the battery and a decent-sized
set of solar panels, you also need all of the associated kit to regulate
the charging and discharging of the batteries.
anyway, I hope at least some of that is useful
Dan
Bolger rules!!!
- no cursing, flaming, trolling, spamming, or flogging dead horses
- stay on topic, stay on thread, punctuate, no 'Ed, thanks, Fred' posts
- Pls add your comments at the TOP, SIGN your posts, and snip away
- Plans: Mr. Philip C. Bolger, P.O. Box 1209, Gloucester, MA, 01930, Fax: (978) 282-1349
- Unsubscribe:bolger-unsubscribe@yahoogroups.com
- Open discussion:bolger_coffee_lounge-subscribe@yahoogroups.com
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