Larry,

I know the answer is somewhere in a search of this newsgroup but I'm feeling
lazy today. I've enjoyed your posts on batteries and would appreciate a
direct recommendation.

I'm probably going to be sailing off a mooring for much of the summer so
often won't even run the engine at all on day sails. I won't have any place
to plug the fat yellow cord into so a solar panel to keep my two AGM
batteries (Yeah, I know you don't like them but they work well for me.)
topped up is probably in order.

What would you buy for the simplest set up here in Maine? It will have to
just sit on a cockpit seat and be stowed while sailing. I'll want to wire it
to a dedicated plug so I can turn off the master switch when I leave the
boat.

Electrical loads are about as minimal as they get on a 32 foot boat, lights,
GPS, one radio, depthsounder, knotlog, 15 HP diesel. Bilge pumps never run.
I always run my batteries on "Both" (I know, but that's another discussion.
It works well for me.)

Come to think of it, I don't want any permanent connection between the
battery banks to complicate things when I am using my dual charger on shore
power with the master switch off so I probably need two separate solar
panels.

(Anyone else feel free with a recommendation as well.)

--
Roger Long

Yo Captain ,, I saw a setup on Ebay that the solar panel is in a suitcase.
When you want to use, you open the suitcase up, and it sets on deck [ as I
recall it was shown for an rv ], run a line to the batteries and let er
power em up.

Whether the panel is any good? Who knows. Seems like much of the solar
panels shown on Ebay are junk.

I'm not sure about regulator, switch, etc.


=============================
"Roger Long" wrote in message
...
Larry,

I know the answer is somewhere in a search of this newsgroup but I'm
feeling lazy today. I've enjoyed your posts on batteries and would
appreciate a direct recommendation.

I'm probably going to be sailing off a mooring for much of the summer so
often won't even run the engine at all on day sails. I won't have any
place to plug the fat yellow cord into so a solar panel to keep my two AGM
batteries (Yeah, I know you don't like them but they work well for me.)
topped up is probably in order.

What would you buy for the simplest set up here in Maine? It will have to
just sit on a cockpit seat and be stowed while sailing. I'll want to wire
it to a dedicated plug so I can turn off the master switch when I leave
the boat.

Electrical loads are about as minimal as they get on a 32 foot boat,
lights, GPS, one radio, depthsounder, knotlog, 15 HP diesel. Bilge pumps
never run. I always run my batteries on "Both" (I know, but that's another
discussion. It works well for me.)

Come to think of it, I don't want any permanent connection between the
battery banks to complicate things when I am using my dual charger on
shore power with the master switch off so I probably need two separate
solar panels.

(Anyone else feel free with a recommendation as well.)

--
Roger Long

Roger, I don't know if this thing is any good.. not much power at 13 watts..
but it is portable.. in a briefcase.
===========


Multi-Purpose 12V Briefcase Solar Generator 13 Watt Power Charger

This product is designed to supply power for outdoor 12V applications. You
will enjoy convenient electricity wherever you go. Your Mobile Power!!

** This auction is for a brand new "black" cover solar generator

Featu

a.. Compact designed, Powerful 13 Watt Solar Charger

b.. With flashing charge indicator to give a clear view that the generator
is working.
c.. With detachable connectors for different application.
d.. With adjustable support panel, help to maximize power output.
e.. With built-in diode to prevent reverse charging.
f.. Can charge a wide range of applications.

g.. Ideal for caravans, motorhomes, yacht, DC fridge, Laptop computer, GPS
System, etc.........
h.. With voltage adaptor, able to charge 3V, 6V, 9V, 12V electronic
appliances (Optional)
i.. With cigarette plug socket (Optional)


Specification:

a.. Use Amorphous silicon solar cells
b.. Power: 13 Watts maximum
c.. Working voltage: equal or greater than 14V
d.. Working current: equal or greater than 750mA
e.. Dimension: 20.07" x 14.76" x 1.57" (510mm x 375mm x 40mm)


"Roger Long" wrote in message
...
Larry,

I know the answer is somewhere in a search of this newsgroup but I'm
feeling lazy today. I've enjoyed your posts on batteries and would
appreciate a direct recommendation.

I'm probably going to be sailing off a mooring for much of the summer so
often won't even run the engine at all on day sails. I won't have any
place to plug the fat yellow cord into so a solar panel to keep my two AGM
batteries (Yeah, I know you don't like them but they work well for me.)
topped up is probably in order.

What would you buy for the simplest set up here in Maine? It will have to
just sit on a cockpit seat and be stowed while sailing. I'll want to wire
it to a dedicated plug so I can turn off the master switch when I leave
the boat.

Electrical loads are about as minimal as they get on a 32 foot boat,
lights, GPS, one radio, depthsounder, knotlog, 15 HP diesel. Bilge pumps
never run. I always run my batteries on "Both" (I know, but that's another
discussion. It works well for me.)

Come to think of it, I don't want any permanent connection between the
battery banks to complicate things when I am using my dual charger on
shore power with the master switch off so I probably need two separate
solar panels.

(Anyone else feel free with a recommendation as well.)

--
Roger Long

"Roger Long" wrote in
:

Come to think of it, I don't want any permanent connection between the
battery banks to complicate things when I am using my dual charger on
shore power with the master switch off so I probably need two separate
solar panels.



I'm not sure how many watts/sq meter you get in Main, Roger, but I'm sure
it's very low in comparison to SC. Let's analyze your loads:

Multiply 13.8V x the amp load of everything that will be running on the
boat....such as anchor light, 13.8V x 1.2A = 16.56W x 12 hours = 198.72
watt-hours each night. (Your spare anchor light bulb may say how many
watts it is, so just multiply that by 12 hours (or more as it gets dark
early in Maine and the sun comes up late).

Do this for every load you can think of. Add up all the Watt-Hours to
get a total. The current usage of the electronics is in the
specifications page of the manual. Do NOT rate them conservatively to
try to get the number down. We're going to ADD more to your answer to
get a relatively "worst case scenario" for our purpose.

Now, I found this Maine Solar House on:
http://www.solarhouse.com/index2.htm
Click on SOLAR DATA on the left panel to get what power they generated
with a whole roof of solar panels, 4,200 watts of them!

In July of 1998, this 4,200 watt, perfectly placed array generated 467KWH
of real power. Let's scale that down to two 80W panels of a perfectly-
placed, unobstructed boat. 80/4200 x 467 = about 8.9KWH in Coastal Maine
in July, about the hottest month when the sun is most North it gets.

Your boat solar cells are never going to make 8.9 KWH for a lot of
reasons.....
1 - The boat moves around on the hook every 6 hours. If we tilt the
panels for best exposure, half the day they're going to be pointed away
from the sun. If we lay them flat, that takes care of that, but the sun
is at an obtuse, inefficient angle, which reduces cell output
accordingly.
2 - The damned rigging shades the panels. Panel output drops like a rock
if anything makes a shadow across the panels. Everything on a sailboat
makes a shadow across the panels at SOME time during a day.

There are many other reasons we can probably identify, including keeping
the salt off the panels which reduces the solar radiation making it
through the glass or plastic cover....

Ok, so it's not going to be easy to figure out how much power you're
going to get from two 80W panels, in reality, but let's work on 5 KWH per
MONTH...not per day. This is 166 watt-hours per day from two 80W panels
on a sailboat. Being most generous, let's say 200 WH per day.

Do you think the anchor light will use it all? The house looks like it's
on a hill, even though it's close to the coast. His air is THINNER than
yours, and he has a lot LESS fog/haze/etc. on his panel roof beast.

So, what happens? The panels don't produce enough power and the
batteries quickly lose the battle going dead, REALLY dead.

I hope this has given you some kind of idea who inefficient solar power
on a sailboat really is...especially that far North. Sure glad I found
that solar house on the Maine Coast. Look how STEEP the panels are set
trying to get perpendicular to those solar rays. Snow won't be much of a
problem...

An 80 watt panel is about 22" x 48" on:
http://www.wholesalesolar.com/products.folder/module-
folder/bp/bp380U.html
When you go to the boat, take a 2x4' sheet of plywood you can't bend with
you. Make believe it's 1-2" thick. Try to find TWO places for TWO
panels on a 32' boat. If you stow the panels up for sailing, you make NO
POWER for the electronics and house batteries underway...making the watt-
hour deficiency even worse.

At noon on their best day, each panel makes a little less than 5A of
power for the few hours in the middle of the day. Bubba would tell you,
"Thait ain't 'nuf, Bo!" Plan on running the engine a few hours to
recharge. Remember we must recharge SLOWLY, not in 10 minutes at
500A....at least not YET given our current lead-acid batteries.

Two panels are $1000, good for 20 years.

All is not lost, however. Maine is WINDY! WIND is our FRIEND, in more
ways than one. Let's compa
http://www.emarineinc.com/products/w...irxmarine.html
I'm not endorsing ANY wind generator product. AirX was the first marine
unit Google found, and is representative of their capabilities.

In a 28 mph breeze, an AirX makes 400 watts of DC. Look at:
http://www.emarineinc.com/products/w...es/airxoutput1
..jpg
Everytime the wind is 13 mph, the AirX puts out as much power as the
solar panel does pointing at the sun, at noon, on its best day....

Question....Are there more windy days on the Maine coast than totally
sunny days...at anchor, swinging in the tide?

The wind genny makes power whichever way the wind is blowing. It cares
less where the boat is pointing or which way the tide is running. It
simply spins around into the wind at an optimal angle for maximum power
generation with NO INPUT ON YOUR PART, which I find very important.
Remember when the solar beasts were stored getting underway? The wind
genny output GOES WAY UP when you add APPARENT WIND to it! Sailboats and
Wind gennys LOVE apparent wind...(c; When we're whipping along with all
the lights and electronic gadgets buzzing away, leaned over on the
handrail, EVEN AT MIDNIGHT, the wind genny sees an apparent wind of 25
mph! Hell, according to this graph, we may have to turn on more than the
running lights! We're making 25A x 14V = 350 watts...AT MIDNIGHT!

I hope you can see the practicality of wind power on your wind-powered
boat over this solar nonsense with the dead batteries and flashlights.
Running the fore-aft-mast running lights all night...that solar panel,
even if you permanently mounted it, is USELESS on the midwatch when the
batteries are going flat. The wind gennys now have special loading
circuits on them so when the batteries get up to full charge, and they
will, the genny's own computer will load the genny to prevent overspeed
and turn excess power into heat.....well, at least until we get BIGGER
house batteries to store it all...(c;

Wind genny is half what two measily solar panels cost. Are you going to
own this boat for 20 years to worry about how long the wind genny will
last? I thought not.

Larry
--
Message for Comcrap Internet Customers:
http://tinyurl.com/3ayl9c
Unlimited Service my ass.....(d^

"Roger Long" wrote in
:

I always run my batteries on "Both" (I know, but that's another
discussion. It works well for me.)


I always run Lionheart's house battery switch on BOTH, but have a separate
crossover switch for the starting battery, which is ALWAYS separate.
There's no way to crank Lionheart's Perkins 4-108 by hand...Hell, you can
hardly get anywhere near the front of the motor. It's buried!

Larry
--
Message for Comcrap Internet Customers:
http://tinyurl.com/3ayl9c
Unlimited Service my ass.....(d^

"NE Sailboat" wrote in news:9FiLh.4296$742.1625
@trndny07:

Multi-Purpose 12V Briefcase Solar Generator 13 Watt Power Charger



13W divided by 12V = a hair over 1A. What are you gonna run with that??

It'll charge cellphone and Ipod batteries....(c;

Larry
--
Message for Comcrap Internet Customers:
http://tinyurl.com/3ayl9c
Unlimited Service my ass.....(d^

On Sun, 18 Mar 2007 22:01:41 GMT, "NE Sailboat"
wrote:

Roger, I don't know if this thing is any good.. not much power at 13 watts..
but it is portable.. in a briefcase.
===========

Here's a link:

http://tinyurl.com/yr3ypv

At $19 it looks like a good value, can't speak to quality. Since it
comes with a cigarette lighter type power adapter, one way to install
it would be to install 2 lighter type outlets in you cockpit area, 1
to each battery, through a small inline fuse.

That particular unit is only 2 watts but if you do an EBAY search on
"12v solar" you will find lots of other possibilities.

On Mon, 19 Mar 2007 01:32:20 +0000, Larry wrote:

I'm not sure how many watts/sq meter you get in Main, Roger, but I'm sure
it's very low in comparison to SC. Let's analyze your loads:

All he's trying to do is keep his batteries topped off.

That doesn't take much power if the batteries are switched off and in
good condition.

I knew that there is no way solar would keep up with my cruising loads.
Cruising in Maine, where the wind usually doesn't come up unitl noon,
usually involves enough motoring to keep the batteries charged. It's the
periods when we're not cruising and just daysailing that I'm concerned
about.

I won't be running the anchor light on the mooring and I just bought one of
the new low draw LED units anyway. My old one was a combination bow/mast
light with two bulbs and was a real hog but it was the only one I could get
when I found that the original was toast the day before the mast was to go
up. The only daysailing draw will be the GPS, radio which I seldom
transmit on (for which I have been already soundly berated on this group),
instruments, and a bit of fresh water pumping.

I also don't expect to keep up entirely with the loads. It's more a matter
of balancing the cost of a modest solar rig against the extension of battery
life and capacity. Maybe just buying new batteries every 2 - 3 years makes
more sense. I get my AGM's cheap enough from a non-marine source that a set
every year would just be a blip in the cost of boat ownership.

Wind is the way to go but location and foundation support are an issue on my
boat.

I'd still like to know if there is a panel that you think makes sense for
this application.

--
Roger Long

The AGM do a good job of holding their charge so this should be much
of a problem. I have two AGM starting batteries and I discovered last
year that they were not getting combined, so one ran most of the
summer without ever getting charged. And the loads from the GPS and
VHF are (probably) pretty small, so in fact you would recover a full
day's use in 10 or 20 minutes of running the engine.

However, it would be prudent to have a panel to make sure the pump
will continue to run, and the engine can be started. There are nice
flexible panels that are convenient - I used one for a few seasons.
They can be toss on the deck, the seat or draped over the boom. You
just want to try to avoid shading. If there's a good spot for a solid
panel, that would put out 2-3 times the power for the price, but the
flexi is more convenient.

The only problem is that they are a bit pricey - the smaller ones that
list around $100 don't have much output. However, it you look on eBay
you might find the same panel that West sells for $200 for half the
price. A 10 Watt panel should do a reasonable job of keeping the
batteries topped off while you're not there.



* Roger Long wrote, On 3/19/2007 6:03 AM:
I knew that there is no way solar would keep up with my cruising loads.
Cruising in Maine, where the wind usually doesn't come up unitl noon,
usually involves enough motoring to keep the batteries charged. It's the
periods when we're not cruising and just daysailing that I'm concerned
about.

I won't be running the anchor light on the mooring and I just bought one of
the new low draw LED units anyway. My old one was a combination bow/mast
light with two bulbs and was a real hog but it was the only one I could get
when I found that the original was toast the day before the mast was to go
up. The only daysailing draw will be the GPS, radio which I seldom
transmit on (for which I have been already soundly berated on this group),
instruments, and a bit of fresh water pumping.

I also don't expect to keep up entirely with the loads. It's more a matter
of balancing the cost of a modest solar rig against the extension of battery
life and capacity. Maybe just buying new batteries every 2 - 3 years makes
more sense. I get my AGM's cheap enough from a non-marine source that a set
every year would just be a blip in the cost of boat ownership.

Wind is the way to go but location and foundation support are an issue on my
boat.

I'd still like to know if there is a panel that you think makes sense for
this application.

--
Roger Long