**


Do those of you with wind generators use them when at sea?  Do you see any
problems with performance as the boat moves with the seas?  I'm not
experienced with either wind or PSA generators, but with wind it seems to me
the wind is driving the wind generator essentially independently of what
it's doing to the sails, unless the wind is coming from astern and
interrupting the flow of air on the sails.  If you're dragging a fixed prop
it wouldn't seem to make much of a difference using a PSA, but if you're
using a feathering prop as many are, the turning prop would seem to me to
create additional drag.

I'm guessing  that just the additional turning of the gears for hours on
end would, at some point, create additional wear on them.  How much,
significant...I wouldn't hazard a guess.

When I do finally get retired and head to the S. Pac, I'll consider both,
and solar as well.

This has been a great discussion...thanks to all.
Kent
SM 243

Kristy

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

 

Well maybe Bill/Judy Sv BeBe will comment on all of this since they are now
in the med and 3/4 of the way round the world

regards

David

On 20 July 2011 16:26, Kent Robertson <karkauai@...> wrote:

**


Thanks, David. I have heard that diesel can be hard to come by in the S
Pac and thought I would need other means of generating my battery power.
Kent

--- On Wed, 7/20/11, David Mackintosh <sv.highland.fling@...> wrote:

From: David Mackintosh <sv.highland.fling@...>
Subject: Re: [Amel] Re: Maramu prop shaft alternator
To: amelyachtowners@...
Date: Wednesday, July 20, 2011, 10:14 AM


Hi Kent

You dont need a fixed prop you can use a MaxProp and 'force' it to stay
open
so you can have regeneration when you want it and no prop drag when you
dont

Most people dont know that you can have the MaxProp stay open to drive a
PSA

IF you have a PSA then use it IF you dont have a PSA Wind and Solar
generation then the CBA for Solar PSA and Wind is very hard to justify vis
a
vis burning diesel....................IF you are limited in your ability to
purchase diesel (you are going to be sailing well off the beaten track)
then that will need serious consideration and may perhaps override the CBA.

I wonder if Bill would chime in here re CBA of wind/solar vis a vis burning
diesel.

regards

David

On 20 July 2011 01:21, Kent Robertson <karkauai@...> wrote:

**


Do those of you with wind generators use them when at sea? Do you see

any

problems with performance as the boat moves with the seas? I'm not
experienced with either wind or PSA generators, but with wind it seems to

me

the wind is driving the wind generator essentially independently of what
it's doing to the sails, unless the wind is coming from astern and
interrupting the flow of air on the sails. If you're dragging a fixed

prop

it wouldn't seem to make much of a difference using a PSA, but if you're
using a feathering prop as many are, the turning prop would seem to me to
create additional drag.

I'm guessing that just the additional turning of the gears for hours on
end would, at some point, create additional wear on them. How much,
significant...I wouldn't hazard a guess.

When I do finally get retired and head to the S. Pac, I'll consider both,
and solar as well.

This has been a great discussion...thanks to all.
Kent
SM 243

Kristy

------------------------------------

Yahoo! Groups Links

Do those of you with wind generators use them when at sea?  Do you see any problems with performance as the boat moves with the seas?  I'm not experienced with either wind or PSA generators, but with wind it seems to me the wind is driving the wind generator essentially independently of what it's doing to the sails, unless the wind is coming from astern and interrupting the flow of air on the sails.  If you're dragging a fixed prop it wouldn't seem to make much of a difference using a PSA, but if you're using a feathering prop as many are, the turning prop would seem to me to create additional drag.
 
I'm guessing  that just the additional turning of the gears for hours on end would, at some point, create additional wear on them.  How much, significant...I wouldn't hazard a guess.
 
When I do finally get retired and head to the S. Pac, I'll consider both, and solar as well.
 
This has been a great discussion...thanks to all.
Kent
SM 243
Kristy

Bill, good sense as always. For me the solar and wind options were fitted because I was not willing to commit to major ocean crossings without an alternative to diesel engines. too many boats (of all sorts) have got into strife over the years losing battery power when an engine fails for whatever reason. It would be a naked feeling to see your battery power ebb away and your lifeline radio and intsrumentation die. We had days of no wind (no boat movement) and days of no sun, but only occasionally no wind and no sun.. When I am potentially weeks from landfall I want more than one option. If I turned off the refrigeration I could be reasonably confident of running radios and instruments without the engines. When we were coming down from Tonga to NZ we heard one very distressed skipper relate that he was running out of battery power as his engine had failed. (he did get it going again)

Far from land I like the belt and braces methods and not too much reliance on the mechanical. At the end of our 16000 miles we were happy
Regards
Danny
SM 299 Ocean Pearl
Mangonui
New Zealand

From: Judy and Bill aboard SV BeBe <yahoogroups@...>
To: amelyachtowners@...
Sent: Thursday, 21 July 2011 7:59 AM
Subject: [Amel] Re: Maramu prop shaft alternator


 
Thanks for the invitation, David. Judy and I have watched this thread and wondered where the heck it was going to wind up.

Our thoughts are not as complicated as this discussion has been. And, our thoughts are limited to what we are doing, which is slowly sailing around the world and stopping to visit the wide variety of people, history and cultures.

When we started we gave a lot of thought to energy and it was easy for us to focus on simple solutions like adding a wind generator or buying solar panels. As a retired CFO, it was fairly simple to build a financial model on the solar panels assuming that we owned a Super Maramu. The bottom line is that the payback on the investment exceeded five years including fuel, maintenance and depreciation. Most of the folks that I have met that invested in wind generators say that they wish they had put their money into solar. And all that I have met that say their wind generator is silent, are hard of hearing.

If you are a Super Maramu owner, you own a very good large generator, charger(s) and have a house battery alternator on the main engine. You are going to maintain your main engine and generator, so the only additional thing you need is diesel. Judy and I are power-using-fools averaging about 150 amps @ 24 volts per day. Since our total fuel costs are less than $2,000USD/year and less than 3% of our total cruising costs, we choose to focus elsewhere when trying to save some money.

With regard to the availability of diesel, we have found it available everywhere. We carried an extra 200 liters on ocean crossings, but never needed it. We have never had to haul jerry-jugs to fuel BeBe.. In out-of-the-way places we have always found an entrepreneur to delver fuel to us. We have bought diesel around the world in various colors and grades. Our choices were limited to what was there and we have not really focused on what we could have bought if we were elsewhere. It has cost us what it was selling for where we bought it. We checked and/or filtered it before it went into the tank and have not used any biocide...but recently started using StarTron Enzyme Fuel Treatment and seem to have a lot less smudge on the port side.

Regarding the shaft alternator, it falls into a category that "sounds good, but." The "but" is that we find it rare to go for 24 hours without running the main engine for an hour or so. So, why would I risk potential problems and 500 - $1,000 to install a shaft alternator. Frankly it will not give us enough amps to offset having to listen to the noise.

Hope this helps.

Bill
BeBe, SM2k, #387
Currently the Greek Islands

--- In amelyachtowners@..., David Mackintosh <sv.highland.fling@> wrote:

Well maybe Bill/Judy Sv BeBe will comment on all of this since they are now
in the med and 3/4 of the way round the world

regards

David

On 20 July 2011 16:26, Kent Robertson <karkauai@> wrote:

**


Thanks, David. I have heard that diesel can be hard to come by in the S
Pac and thought I would need other means of generating my battery power.
Kent

--- On Wed, 7/20/11, David Mackintosh <sv.highland.fling@> wrote:

From: David Mackintosh <sv.highland.fling@>
Subject: Re: [Amel] Re: Maramu prop shaft alternator
To: amelyachtowners@...
Date: Wednesday, July 20, 2011, 10:14 AM


Hi Kent

You dont need a fixed prop you can use a MaxProp and 'force' it to stay
open
so you can have regeneration when you want it and no prop drag when you
dont

Most people dont know that you can have the MaxProp stay open to drive a
PSA

IF you have a PSA then use it IF you dont have a PSA Wind and Solar
generation then the CBA for Solar PSA and Wind is very hard to justify vis
a
vis burning diesel....................IF you are limited in your ability to
purchase diesel (you are going to be sailing well off the beaten track)
then that will need serious consideration and may perhaps override the CBA.

I wonder if Bill would chime in here re CBA of wind/solar vis a vis burning
diesel.

regards

David

On 20 July 2011 01:21, Kent Robertson <karkauai@> wrote:

**


Do those of you with wind generators use them when at sea? Do you see

any

problems with performance as the boat moves with the seas? I'm not
experienced with either wind or PSA generators, but with wind it seems to

me

the wind is driving the wind generator essentially independently of what
it's doing to the sails, unless the wind is coming from astern and
interrupting the flow of air on the sails. If you're dragging a fixed

prop

it wouldn't seem to make much of a difference using a PSA, but if you're
using a feathering prop as many are, the turning prop would seem to me to
create additional drag.

I'm guessing that just the additional turning of the gears for hours on
end would, at some point, create additional wear on them. How much,
significant...I wouldn't hazard a guess.

When I do finally get retired and head to the S. Pac, I'll consider both,
and solar as well.

This has been a great discussion...thanks to all.
Kent
SM 243

Kristy

------------------------------------

Yahoo! Groups Links

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

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

I think you will find a wind generator is not really usable when sailing in
decent winds and seas as gyroscopic effects and precession all start to have
a serious effect.

You are correct of course water being denser than air it is much easier to
extract power from a water driven propeller. BUT i think you miss the point
- lets say a PSA producing 10/15 Amp takes 1.5 HP to drive That HP has to
come from somewhere - the sails :-) To get your say what 22 metric ton
Amel up to hull speed is going to take say 80 HP so the losses assuming
they can be measured in a real live real time situation are going to be
insignificant really

Plus if you have 150/200 HP from your sails you have an excess of power and
since your Amel cant get up and plane - you have oodles of spare free HP to
drive your PSA. Any time you have more power from your sails than that
needed to drive the boat at hull speed..there will be no actual loss of
performance when using the PSA.

Actual real time real life reports on the PAS performance say the losses are
insignificant - not really measurable.

Now lets look at the trasmission designed to drive this 22MT boat with say
70 SHP..............do you really think you can damage that transmission in
any way by powering a 1.5 HP PSA with it? I think NOT!!!

IF anyone wants to dump their PSA then please contact me i would love to
have it :-)

regards

David

On 20 July 2011 00:13, Dave_Benjamin <dave_benjamin@...> wrote:

**


I'm a bit confused about the comparison in losses between the PSA and a
wind generator. Water is far denser than air. The prop becomes a speed brake
of sort. I'm not a physicist but I'd wager that amp for amp the performance
loss with a wind generator is negligible compared to a PSA.

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

**


David,

In my flying career I spent close to 5000 hours in large turbo-prop
aircraft so gyroscopic effects are well known to me. (Not all twin engine
aircraft have counter-rotating props). In any case, perhaps you can explain
how "P-factor" would impair a wind generator that is free to swivel. The
force vector is going to simply cause it to rotate one way or the other,
isn't it? Given the movement of the boat, there's not going to be a steady
force in any one direction.

--- In amelyachtowners@..., David Mackintosh
<sv.highland.fling@...> wrote:

I think you will find a wind generator is not really usable when sailing

in

decent winds and seas as gyroscopic effects and precession all start to

have

a serious effect.

You are correct of course water being denser than air it is much easier

to

extract power from a water driven propeller. BUT i think you miss the

point

- lets say a PSA producing 10/15 Amp takes 1.5 HP to drive That HP has to
come from somewhere - the sails :-) To get your say what 22 metric ton
Amel up to hull speed is going to take say 80 HP so the losses assuming
they can be measured in a real live real time situation are going to be
insignificant really

Plus if you have 150/200 HP from your sails you have an excess of power

and

since your Amel cant get up and plane - you have oodles of spare free HP

to

drive your PSA. Any time you have more power from your sails than that
needed to drive the boat at hull speed..there will be no actual loss of
performance when using the PSA.

Actual real time real life reports on the PAS performance say the losses

are

insignificant - not really measurable.

Now lets look at the trasmission designed to drive this 22MT boat with

say

70 SHP..............do you really think you can damage that transmission

in

any way by powering a 1.5 HP PSA with it? I think NOT!!!

IF anyone wants to dump their PSA then please contact me i would love to
have it :-)

regards

David

On 20 July 2011 00:13, Dave_Benjamin <dave_benjamin@...> wrote:

**


I'm a bit confused about the comparison in losses between the PSA and a
wind generator. Water is far denser than air. The prop becomes a speed

brake

of sort. I'm not a physicist but I'd wager that amp for amp the

performance

loss with a wind generator is negligible compared to a PSA.

**


David,

In my flying career I spent close to 5000 hours in large turbo-prop
aircraft so gyroscopic effects are well known to me. (Not all twin engine
aircraft have counter-rotating props). In any case, perhaps you can

how "P-factor" would impair a wind generator that is free to swivel. The
force vector is going to simply cause it to rotate one way or the other,
isn't it? Given the movement of the boat, there's not going to be a steady
force in any one direction.

--- In amelyachtowners@..., David Mackintosh
<sv.highland.fling@...> wrote:

I think you will find a wind generator is not really usable when sailing

in

decent winds and seas as gyroscopic effects and precession all start to

have

a serious effect.

You are correct of course water being denser than air it is much easier

to

extract power from a water driven propeller. BUT i think you miss the

point

- lets say a PSA producing 10/15 Amp takes 1.5 HP to drive That HP has

come from somewhere - the sails :-) To get your say what 22 metric ton
Amel up to hull speed is going to take say 80 HP so the losses assuming
they can be measured in a real live real time situation are going to be
insignificant really

Plus if you have 150/200 HP from your sails you have an excess of power

and

since your Amel cant get up and plane - you have oodles of spare free HP

to

drive your PSA. Any time you have more power from your sails than that
needed to drive the boat at hull speed..there will be no actual loss of
performance when using the PSA.

Actual real time real life reports on the PAS performance say the losses

are

insignificant - not really measurable.

Now lets look at the trasmission designed to drive this 22MT boat with

say

70 SHP..............do you really think you can damage that transmission

in

any way by powering a 1.5 HP PSA with it? I think NOT!!!

IF anyone wants to dump their PSA then please contact me i would love to
have it :-)

regards

David

On 20 July 2011 00:13, Dave_Benjamin <dave_benjamin@...> wrote:

**


I'm a bit confused about the comparison in losses between the PSA and

wind generator. Water is far denser than air. The prop becomes a speed

brake

of sort. I'm not a physicist but I'd wager that amp for amp the

performance

loss with a wind generator is negligible compared to a PSA.

OHHHH a moderator in waiting AND one with a crystal ball to who speaks for
'most of us' on the group

OH MY :-(

David

On 22 July 2011 19:45, thomas.kleman@... <thomas.kleman@...>wrote:

**


All- while I enjoy and learn from most of the threads, of late there has
been quite a bit of dreary pablum and self aggrandizement by people who
must
have missed the "amelyachtowners" part of the URL. Like most people, I
belong to several groups outside of this one for general sailing info. This

group is valuable to me (and dare I speak for most of us) because it is
AMEL
specific. Someone's flying resume would seem to fail the relevance test. As

the site supports direct person to person email for these enthralling
exchanges of credentials, perhaps we can keep the site clear of them in the

future.

Connected by DROID on Verizon Wireless


-----Original message-----
From: David Mackintosh <sv.highland.fling@...>
To: amelyachtowners@...
Sent: Fri, Jul 22, 2011 13:39:13 GMT+00:00
Subject: Re: [Amel] Re: Maramu prop shaft alternator

Well what can i say,

My flying starts with PA28's and included the PA 30 with non contra
rotating
props and the PA 39 with contra rotating props and goes all the way up to
the L1011 B757 and even the LHD Death Cruiser he he.

The P factor will i suspect actually de power the wind generator sadly i
dont have the time or the motivation to actually sit down and calculate
this
- perhaps introducing the P factor into this discussion was not helpful -
it
is as you probably fully understand one of 'the results' which is why i did
include it.

All i know is real time actual results. When i was sailing with many of my
friends in the Caribbean they tied off their W/G's when out sailing in
20+knots of wind as they complained of 'problems' in high winds and big
seas. Now they were all on dedicated W/G poles or Radar Arches. Having the
W/G on the mast well you may not notice 'issues' as the mast is supported
to
handle sail loadings.

But we have all played with a gyroscope i am sure and we know how hard it
is
to move it when it is spinning - put that gyroscope/W/G on the end of a 10
foot pole or even a 30 foot mast and well you are amplifying that effect.
Now put that pole/mast on a sailboat that is moving in a variety of
directions at unpredictibale speeds and rates of change and you are
introducing some serious loads to your W/G mount(s).

I can see a use for wind generators at anchor in anchorages with >10knots
of wind and for sure they work when the sun does not shine - like i
explained i am conflicted as to the CBA vis a vis burning diesel and
purchasing and installing W/G and Solar. I should add i dont have an Amel
nor a generator on board and as we have added more and more electrical
loads
we need to seriously look at some means of generating more electricity
'MOSTLY' when we are sailing as the autopilot and all the new electronics
and new 12V freezer (soon new 12V Fridge) and other loads mean that on
passage (only inter island stuff 8 to 16 hours at most) we need to either
run the engine (do some gentle motor sailing) or selectively switch on and
off various bit of kit as well as hand steer for a while something we enjoy
in the heavy weather but not for 8 or more hours. We have a Raymarine E120
plotter and that is too heavy on power consumption for use all the way
through any inter island passage but we have a Raymarine Raynav 320 which
uses much less power so that gets used for power saving navigation. As they
both talk to each other we can share waypoints etc. Obviously the E120 does
much more for us but ATM its power consumption is unsustainable for inter
island passages. I would love a PSA and i am planning to put one on our
boat
ASAP my preference would be to use a PMA as a PSA but cant see an easy way
of stopping that charging - sounds like a job for a lead screw to adjust
belt tensioning or diverting that output to a 12V element in the hot water
tank IF or once the batteries are fully charged. Obviously the normal
car/boat style alternator has advantages in a PSA application as you can
simply switch it on and off BUT the down side of that is that to power the
coils and excite the alternator you are going to use 1 amp.

To get back to non contra rotating props :-) i am always amazed and it is
fun to watch and to see the difference in reaction and rotation of twin
W/G's on other boats.

regards

David

On 22 July 2011 02:07, Dave_Benjamin <dave_benjamin@...> wrote:

**


David,

In my flying career I spent close to 5000 hours in large turbo-prop
aircraft so gyroscopic effects are well known to me. (Not all twin engine
aircraft have counter-rotating props). In any case, perhaps you can

explain

how "P-factor" would impair a wind generator that is free to swivel. The
force vector is going to simply cause it to rotate one way or the other,
isn't it? Given the movement of the boat, there's not going to be a

steady

force in any one direction.

--- In amelyachtowners@..., David Mackintosh
<sv.highland.fling@> wrote:

I think you will find a wind generator is not really usable when

sailing

in

decent winds and seas as gyroscopic effects and precession all start to

have

a serious effect.

You are correct of course water being denser than air it is much easier

to

extract power from a water driven propeller. BUT i think you miss the

point

- lets say a PSA producing 10/15 Amp takes 1.5 HP to drive That HP has

to

come from somewhere - the sails :-) To get your say what 22 metric ton
Amel up to hull speed is going to take say 80 HP so the losses assuming
they can be measured in a real live real time situation are going to be
insignificant really

Plus if you have 150/200 HP from your sails you have an excess of power

and

since your Amel cant get up and plane - you have oodles of spare free

HP

to

drive your PSA. Any time you have more power from your sails than that
needed to drive the boat at hull speed..there will be no actual loss of
performance when using the PSA.

Actual real time real life reports on the PAS performance say the

losses

are

insignificant - not really measurable.

Now lets look at the trasmission designed to drive this 22MT boat with

say

70 SHP..............do you really think you can damage that

transmission

in

any way by powering a 1.5 HP PSA with it? I think NOT!!!

IF anyone wants to dump their PSA then please contact me i would love

to

have it :-)

regards

David

On 20 July 2011 00:13, Dave_Benjamin <dave_benjamin@> wrote:

**


I'm a bit confused about the comparison in losses between the PSA and

a

wind generator. Water is far denser than air. The prop becomes a

speed

brake

of sort. I'm not a physicist but I'd wager that amp for amp the

performance

loss with a wind generator is negligible compared to a PSA.

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

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

------------------------------------

Yahoo! Groups Links


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

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