Is there a cheap and easy solar charger available, that I can use to
keep the batteries full when I don't use the boat in a while? I just
want it to maintain the charge, so that I can be sure to return to
full batteries after a while of non-use, and don't have to deal with
shore power cable and charger. It needs to be able to sit outside, in
the cockpit.

There would be no load other than keeping the batteries (two, I think
54 Ah each) topped off.

Thanks!

wrote in message
oups.com...

Is there a cheap and easy solar charger available, that I can use to
keep the batteries full when I don't use the boat in a while? I just
want it to maintain the charge, so that I can be sure to return to
full batteries after a while of non-use, and don't have to deal with
shore power cable and charger. It needs to be able to sit outside, in
the cockpit.

There would be no load other than keeping the batteries (two, I think
54 Ah each) topped off.

Thanks!


Yah, one of the little 5 amp solar trickle chargers should be able to do
that for you. Boatus, Defender, even auto supply stores should carry them.

On Sun, 1 Apr 2007 14:44:17 -0500, "KLC Lewis"
wrote:


wrote in message
roups.com...

Is there a cheap and easy solar charger available, that I can use to
keep the batteries full when I don't use the boat in a while? I just
want it to maintain the charge, so that I can be sure to return to
full batteries after a while of non-use, and don't have to deal with
shore power cable and charger. It needs to be able to sit outside, in
the cockpit.

There would be no load other than keeping the batteries (two, I think
54 Ah each) topped off.

Thanks!


Yah, one of the little 5 amp solar trickle chargers should be able to do
that for you. Boatus, Defender, even auto supply stores should carry them.


Little 5 *amp*?

KLC Lewis wrote:
wrote in message
oups.com...
Is there a cheap and easy solar charger available, that I can use to
keep the batteries full when I don't use the boat in a while? I just
want it to maintain the charge, so that I can be sure to return to
full batteries after a while of non-use, and don't have to deal with
shore power cable and charger. It needs to be able to sit outside, in
the cockpit.

There would be no load other than keeping the batteries (two, I think
54 Ah each) topped off.

Thanks!


Yah, one of the little 5 amp solar trickle chargers should be able to do
that for you. Boatus, Defender, even auto supply stores should carry them.


A 5 amp solar charger isn't little. That's about what I get from an 85
watt panel in full sun. The panel is 42" x 28.5" x 1.4" Maybe you were
thinking 5 WATTS

"Goofball_star_dot_etal" wrote in message
...
On Sun, 1 Apr 2007 14:44:17 -0500, "KLC Lewis"
wrote:


wrote in message
groups.com...

Is there a cheap and easy solar charger available, that I can use to
keep the batteries full when I don't use the boat in a while? I just
want it to maintain the charge, so that I can be sure to return to
full batteries after a while of non-use, and don't have to deal with
shore power cable and charger. It needs to be able to sit outside, in
the cockpit.

There would be no load other than keeping the batteries (two, I think
54 Ah each) topped off.

Thanks!


Yah, one of the little 5 amp solar trickle chargers should be able to do
that for you. Boatus, Defender, even auto supply stores should carry them.


Little 5 *amp*?



Watt. I meant Watt.

On Sun, 1 Apr 2007 15:33:48 -0500, "KLC Lewis"
wrote:


"Goofball_star_dot_etal" wrote in message
.. .
On Sun, 1 Apr 2007 14:44:17 -0500, "KLC Lewis"
wrote:


wrote in message
egroups.com...

Is there a cheap and easy solar charger available, that I can use to
keep the batteries full when I don't use the boat in a while? I just
want it to maintain the charge, so that I can be sure to return to
full batteries after a while of non-use, and don't have to deal with
shore power cable and charger. It needs to be able to sit outside, in
the cockpit.

There would be no load other than keeping the batteries (two, I think
54 Ah each) topped off.

Thanks!


Yah, one of the little 5 amp solar trickle chargers should be able to do
that for you. Boatus, Defender, even auto supply stores should carry them.


Little 5 *amp*?



Watt. I meant Watt.


Watts[sic] a factor of 15 or so between sailors, m'lud.

Harbor Freight offers a 1.5 watt solar charger for $20. It plugs into a
cigarette lighter socket. They are also offering a 5 watt unit for $50.
This
one clips to the battery.. They also have an 18-24 volt model for $140 and
a
16 watt unit for $180.
5 watts probably won't do the job of re-charging. It might be able to keep
the 2 batteries topped up once they were fully charged by some other means.

A 5 watt panel would probably output something like .4 amp under perfect
conditions. Depending on where you are, perfect condition are probably an
hour a day, with less than perfect for 6-10 hrs a day and no charging the
rest of the time.

If you assume that you get 1 hr of optimum charging = .4 amp/hr
plus 8 hrs of less than optimal @ .25 amps = 2 amp/hrs
Total 2.4 amp/hrs per 24 hour period.

At this rate, assuming your batteries are 50% discharged, it would take
22-23 days to re-charge them if batteries were 100% efficient when charging,
but they're not, so figure 26-30 days to recharge both batteries from 50%
discharged.

In summary - you will probably need more panel output if you want the panel
to recharge rather than maintain a charge. I'd suggest 20-30 watts might be
more like it as a minimum.

Optimum for solar panels is when the sun is directly shining on them at full
intensity with no shadows at all. When the sun is lower in the sky the
efficiency is lower, any shadows may reduce the output drastically.

"Hobbs" wrote in message
...

In summary - you will probably need more panel output if you want the
panel to recharge rather than maintain a charge. I'd suggest 20-30 watts
might be more like it as a minimum.


One other thing - if you have enough solar cell capacity to do a useful job
of charging then you also need a way to control the output of the solar
cells once the batteries are fully charged. So you'd better also budget for
a solar panel regulator.

Good luck with the project

Thank you, that's what I am looking for; do you know if any of these
is weatherproof, i.e. can sit in the cockpit?

Thanks!

Apr 1, 2:08 pm, Gogarty wrote:
In article ,
says...

Harbor Freight offers a 1.5 watt solar charger for $20. It plugs into a
cigarette lighter socket. They are also offering a 5 watt unit for $50. This
one clips to the battery.. They also have an 18-24 volt model for $140 and a
16 watt unit for $180.

There would be no load other than keeping the batteries (two, I think 54 Ah each) topped off.

Can someone knowledgeable estimate the float current needed to keep
these batteries at full charge??