Power: Solar, wind, lights, towed....???

[Cmdr Pete]

From what I understand, there are two types of panels--multicrysteline and amorphous silicon.

Each have pros and cons.

Amorphous silicon panels (like those) need to be larger for the same power. A 50 W multicrysteline panel might be 2 sq ft.

Finding a place to mount them may be a problem

Anyway, here is a useful site if you order things fom Harbor Freight

http://www.billt.com/harborfreight.htm

[AdriftAtSea]

Actually, there are three types of panels. 

Thin film or amorphous silicon have the lowest efficiency, but can be made in semi-rigid and flexible forms, including ones that can be worked on.  These are often the easiest to install.

Polycrystalline and monocrystalline panels are more efficient, but must be made in a rigid form, usually with aluminum frames and glass covers. 

One thing that affects all of the solar panels is temperature.  As the temperature goes up, their efficiency goes down.  If you're planning on mounting polycrystalline or monocrystalline panels, make sure that some air can get behind the panels to help keep them cool.

[Cmdr Pete]

I've been toying with the idea of mounting a solar panel on my forward hatch.

The Ariel has the same hatch. Its about 21 1/4" X 15 1/2" (550 X 400 mm). The hatch has some crown to it, so a flexible panel would be best. But, they produce much less power and I haven't found the right size.

Semi-rigid panels bend about 3-5%. Maybe not enough.

If I get a rigid panel, I could install it with corner brackets so it doesn't snag a line.

Maybe too ugly

This is what I found so far

About $180
http://www.kyocerasolar.com/pdf/specsheets/ks20.pdf

http://www.mrsolar.com/page/MSOS/PROD/wattsort/SC-24-12V

Cheap, but not much power

http://www.mrsolar.com/page/MSOS/PROD/wattsort/US-11

Some expensive offerings

http://tinyurl.com/18r

http://www.sunware.de/US/Products/Solar%20Modules/Data%20sheets/DatenSW_3063_US.htm




(Edit: Added tinyurl. :) )

[s/v Faith]

Don't know but.....

Man that seahood is a nice peice of work.   ;D

[maxiSwede]

Has anyone here got experience with the flexible panels. I mean those with grommets in the corners, to be lashed at the guardrails for instance. And when not in use, stowed under deck. Since they are not on a fixed mounting they could be placed where they would get the most sunshine...

Sounds good or ,...?  My long-time idols, the Pardeys have got one these days. They got high-tech at last  ;)

[Godot]

Has anyone here got experience with the flexible panels. I mean those with grommets in the corners, to be lashed at the guardrails for instance. And when not in use, stowed under deck. Since they are not on a fixed mounting they could be placed where they would get the most sunshine...

Sounds good or ,...?  My long-time idols, the Pardeys have got one these days. They got high-tech at last  ;)

I have one.  I don't think they are really all that effective at charging a battery as the wattage is really low.  Heck, with the panel I have you don't even need a charge controller.  Also, I found mine was light enough that when a decent breeze came across the deck it would want to fly.  Four lines to four separate mountings kept it from going far; but it made a racket every time it slammed back into the deck.

Mine, if I remember right is something like 5 watts.  Let's see, average five hours charge time on a twelve volt system... 5hr * 5w/12v = 2.08 amp hours a day.  Maybe more down south, less up north.  Maybe it's enough to drive an LED anchor light and cover the self discharge of a battery.  Maybe.  They are strong, though.  You can use the panel for a welcome mat if you really want.  And they are easy to store.

I understand they have some bigger panels which would probably be better.  A 20 watt panel is 12"x73" (305 x 1858mm) which is pretty big and might be a handfull on deck (especially when sailing).  A 20 watt Duralite Solar Panel is 24.5"x20" (or a little more than half the size of the flexible panel) for comparison.  Or, for similar dimensions to the Duralite (20.7" x 25.7") you could get a Kyocera 43 watt panel which with 5 hours of sunshine could give you almost 18 amp-hours (and for only $259.99 at Defender). 

But then, mounting a rigid flat panel isn't always easy on a boat, which tend not to have many flat surfaces available.  Oh, well.  BTW, I'm taking the advertised specs at their word.  I'm sure there is some loss in these systems and I understand different manufacturers use different methods to determine their rating.  What do I know?

Personally I feel the roll up panels are fine to keep the batteries from self discharging and to extend the battery life slightly on a several day cruise.  Sailfar-ther than that, though, and they probably aren't the best.

[skylark]

You definitely have to watch how big the panels are compared to how much power they put out.  You will run out of places to mount them, so you might as well get the most space efficient panels you can get.

This system looks good:

http://www.svguenevere.com/2006/gear/solar.html

[CharlieJ]

we have a Unisolar flexible panel. 32 watts and 2 amps. Does all we need for the moment. We have it mounted on the top of our bimini and it stays there all the time.

It supplied all the juice we needed on a 33 day cruise this past May and June including three nights offshore with running lights lit, and radio on full time.. But then we are pretty frugal on our electrical usage other wise..

Your mileage may vary ;D

You can see our mounting in this picture-

[maxiSwede]

Thanks to all of you nice sailfar-guys for the info.

It´s funny, here in Sweden I have yet not seen any chandler selling the flexible panels. In the UK they sell a 30W unit 1440x 5xx  millmeters for a little more than 400 € (530 USD) Which I guess could cover my needs when at the hook.
(pretty much the same as Charlie´s I guess)

When sailing, I am thinkiing of an aquaGen (water generator; not sure of the name in English) that gives about 1 Amp/knot boat speed.

I have never in 30 years of sailing felt the need for more electricity than the occassional 30 min of motoring has supplied. In spite of my KISS philosophy though, I have fallen for the temptation of a lap-top with charts and nav.programs and the posiibily of recieving weather fax´s.

Got it REALLY cheap from a guy who just came home from a circumnavigation.
;D
The downside is the da--n laptop is thirsty on amphours, and so the need for some ¨home-made¨ electricity on board the ship.

Yeah, right I know: You buy one ¨nice-to-have¨ gadget and ends up needing two more, which then leads you to the need on more of... :(

What can I say to my defence... even the Pardeys have it  8) 8)  uhrmm

[AdriftAtSea]

The water generators really are only good when you're making a long passage... on shorter ones, they tend to be a bit of a pain... One company makes a dual-use water/air generator—which is nice because the air generator can be used at anchor, and the water generator can be used while making passages.

Personally, I like solar panels since they're relatively simple to setup, and relatively low-maintenance overall.  The two I got for Pretty Gee are rather large 80W panels and work in even lower light conditions than I was expecting.  One panel will put out almost 19 amps mid-day during the spring... which was rather surprising when I found out...as it cost me a few 10 and 15 amp fuses before I realized what was going on. 

I think, given my relatively modest electrical needs, that I can be completely independent in terms of electricity as long as I get a sunny day every other day or so... I think I'd have to beef up the battery banks if I wanted to go longer than that without good sun. 

[maxiSwede]

Two 80 W panels!?  Don´t they cover the entire deck? They must be huge...  ???

[Captain Smollett]

One panel will put out almost 19 amps mid-day during the spring...

That's only 4V (80 W / 19 amp). Are you sure things are wired correctly?

4V won't charge a battery.  Even at 'parade rest,' a batt is over 10 V.  To charge a battery properly, you need ballpark 14 V (depending on the batt).  Most solar panels I've seen have specs for around 16 V.  At 16V, your 80W panel should be outputting around 5 amp.

I'm obviously very confused about how an 80 W panel is delivering 19 amps.

[AdriftAtSea]

My bad...just checked the e-mail invoice and the manufacturer has them rated as 140W panels, not 80W.  :D

I believe the actual output at the time was about 18.3 A at 13.5 Volts (according to the display on the charge controller) at the time I did that particular test.... so I think they're actually quite conservatively rated.  I'd have to check my boat book for the details of the test.

Yes, the panels are rather large—28" x 60" x 2" or so each.  But the system I am using to mount them keeps them out of the way and fairly well oriented, but not perfectly aligned with the sun.  They're mounted on rails that mount between the cockpit pulpit and the ama. 

[s/v Faith]

Dan,

  Do you have a picture of this?  I am trying to figure out my mount, while avoiding the 'skylab' motif.....

  Maybe it is easier to find places to mount solar panels on a folding tri  ???

My bad...just checked the e-mail invoice and the manufacturer has them rated as 140W panels, not 80W.  :D

I believe the actual output at the time was about 18.3 A at 13.5 Volts (according to the display on the charge controller) at the time I did that particular test.... so I think they're actually quite conservatively rated.  I'd have to check my boat book for the details of the test.

Yes, the panels are rather large—28" x 60" x 2" or so each.  But the system I am using to mount them keeps them out of the way and fairly well oriented, but not perfectly aligned with the sun.  They're mounted on rails that mount between the cockpit pulpit and the ama. 

[Captain Smollett]

I believe the actual output at the time was about 18.3 A at 13.5 Volts (according to the display on the charge controller) at the time I did that particular test....

So, that's 247 Watts - is that for both panels at the same time?  If so, that seems pretty reasonable.

That's a LOT of juice, man.  If you get 5 hrs charge time at that rate, that's 90 amps per day.

You gotta microwave on board you have not told us about?   ;D

[AdriftAtSea]

For some reason I seem to remember only having one of the panels actually out for the testing, since I was testing the wiring from the cockpit sockets to the solar panel charge controller.  I'd have to check my boat book to see if that was actually the case.  I ordered the panels before I realized how big they were and how much juice they were going to give me, because a friend of mine had gotten me a really good price on them.  :D  They are a bit overkill...unless I decide to add an SSB-radio or radar to the boat.   

As for how they're mounted...the skylab thing isn't too far from the mark. These are some photos of the port-side panel being mocked up, back when the mounts were being fabricated for me. 

[Lynx]

????
At what point do you need solar powers vers engin charging?

My outboard puts out 12 amps at 2000 rpm's and will run 4 hrs on a galon of gas. That is over 500 watts in 1 hrs.

Should I get a 48W solar pannel to cruise the Bahamas and East Coast?

[Captain Smollett]

????
At what point do you need solar powers vers engin charging?

My outboard puts out 12 amps at 2000 rpm's and will run 4 hrs on a galon of gas. That is over 500 watts in 1 hrs.

Should I get a 48W solar pannel to cruise the Bahamas and East Coast?

For my part, I do not like relying on the engine for charging.  To quote someone on the TSBB forum, you can count on engines to do one thing: FAIL.  The rags are full of stories of trips ending prematurely due to engine failure, followed by failure of all the other 'systems' that depended on the engine.

I am trying to COMPLETELY shift my thinking to the simple fact that the boat is a SAILING machine.  The engine may be a convenience, but I will NOT rely on it for ANYTHING.  Other reasons, imo, to resist relying on engine charging include: burning up fuel on an otherwise "clean" sailing passage, noise pollution in a quiet anchorage, etc.

All that said, I would also not put all my charging needs into ANY one single basket - that is, if I really NEED those electric applicances.  So yes, I personally would add a solar panel to the existing system.  Each (the panel and your ob) can back the other up - the ole belt-n-suspenders approach.

A 48 W panel with a 5 hour per day charge time should give you enough juice to not even need to fire up that ob (depending upon what you are powering aboard of course).

My $0.02.

[Godot]

????
At what point do you need solar powers vers engin charging?

My outboard puts out 12 amps at 2000 rpm's and will run 4 hrs on a galon of gas. That is over 500 watts in 1 hrs.

Should I get a 48W solar pannel to cruise the Bahamas and East Coast?

Not to speak for anyone else; but I think it is largely a matter of personal esthetics and preference.  Lots of people charge their batteries with engines.  Noise.  Pollution.  Wear and tear on the engine.  Reliance on a mechanical device.  A tie to the fuel station.  Solar power is clean and self sufficient.  Highly reliable.  Completely dependent on the sun shining, though.  And it takes deck space, controllers, and an initial investment.

Do you NEED solar?  Nope.  But neither do you NEED electricity.  Is all personal.

BTW, my outboard doesn't put out anywhere near 12 amps. 

[AdriftAtSea]

For my part, I do not like relying on the engine for charging.  To quote someone on the TSBB forum, you can count on engines to do one thing: FAIL.  The rags are full of stories of trips ending prematurely due to engine failure, followed by failure of all the other 'systems' that depended on the engine.

I am trying to COMPLETELY shift my thinking to the simple fact that the boat is a SAILING machine.  The engine may be a convenience, but I will NOT rely on it for ANYTHING.  Other reasons, imo, to resist relying on engine charging include: burning up fuel on an otherwise "clean" sailing passage, noise pollution in a quiet anchorage, etc.

All that said, I would also not put all my charging needs into ANY one single basket - that is, if I really NEED those electric applicances.  So yes, I personally would add a solar panel to the existing system.  Each (the panel and your ob) can back the other up - the ole belt-n-suspenders approach.

A 48 W panel with a 5 hour per day charge time should give you enough juice to not even need to fire up that ob (depending upon what you are powering aboard of course).

My $0.02.

I'd heartily agree with CS regarding engines being a source of failure.  If you've read Tania Aebi's Maiden Voyage, you'd realize how often she had engine trouble that often left her with no way to recharge her batteries, and in some cases without electrical power at all.   Also, one point he didn't make is that to charge the batteries via the engine, you need fuel. Fuel is heavy and takes up space, and once at sea, becomes a scarce resource, and better used where it is more needed—moving the boat under engine power if necessary, rather than for charging batteries that could easily be charged with renewable energy sources—wind, water and solar.

In fact, the solar panel system I have on the PG has redundancy built into it, as either panel alone should provide me with enough electricity to be fairly independent, provided the sun is shining... the OB is a tertiary charging source in many ways.