my kc85watt panel makes a lot of juice,i used one panel lying flat and it produces power until sundown,also the kc panel has a 25 year warrenty,and it produces up to 16.6 volts and 5.1 amps max. next year i will mount 2-85watt panels on an arch woo hoo .....rayder
I work for a solar panel manufacturer. I am a manufacturing engineer. My department actually cuts the wafers that are made into cells. We make rigid panels for residential and commercial use. I have an old panel of ours from the 90's that is for marine use. We no longer make these, unfortunatly. Anyway, I will let you all know that thin film panels are the holy grail of solar. No one has a flexible/rollable panel that will compete with a rigid over time. The way they are currently made, by depositing silicon vapor on a flexible film, panels will not last more than 2 years. It is very difficult to maintain the integrity of a very brittle material while is is allowed to flex. Don't waste your money on non-rigid panels. I have seen some very lightweight panels that have the cells mounted to corrugated plastic. These are for use at dock or at anchor and cannot withstand high winds. I don't know who makes them, but they are out there.
Alas, I came across a reference that said that all thin film solar (which includes amorphous), tends to degrade after exposure to sun + time (no I'm not making this up) by about 15%-35% depending on the type/manufacturing details. This doesn't even include the possibility of the plastic on top yellowing. Or breakage from flexing. This would seem to wipe out any additional performance flexible, amorphous might have over the crystaline variety. Too bad. It does seem like thin film panels are the future of the solar market since they have the *potential* to be manufactured much cheaper; although the best new developments there seem to be focusing on the utility and home markets. It might be a long time before something more useful to sailboats makes it to the market. I think I'm going to focus on wind/water power for this season and think some more about the best place to mount some rigid panels on my boat.
wind_magic, I do love the idea of panels glassed into the deck and think there is a definite future there. I guess we'll have to wait and see.
nickmerc, Thanks for confirming what I am learning. Seems like rigid is the only way to go. I haven't seen any thin film rigid panels that would make sense for boats, are you aware of any?
Unless you hear differently from some actual users, I think that you should not assume the panels will outlast their warranty periods, expecially if they are exposed to the sun daily.
Huh?!??!
I thought exposing them to the sun daily was the fundamental principle behind the product.
FWIW I am not a supporter of solar because to me, the power is not sufficient for the cost and frankly I think they are really ugly. Wind gennies to me are a contradiction on terms. When I go on anchor I spend a great deal of effort finding a spot with the least wind. And coincidentally that's about the time I am likely to use the most power.
Genset for me . . . . low fuel usage, more power than I can use, almost as quiet as a solar array, far quieter than most wind gennies. I haven't got a functional one yet but am working on that - will definitely have one working before I go off cruising.
JMHO
__________________ "I think it would be a good idea"
Response from Mahatma Ghandi when asked what he thought of Western Civilisation.
i think that it's a proven fact that rigid panels outperform the flexible panels. Putting panels on a sailboat is an issue as well because of the shadows of the mast, boom, and sails. The answer as I see it is to install rigid panels either on a dedicated arch or pole mount close to the stern or along either side of the stern pulpit in a manner that allows them to hinge upward for use and down for marina situations. Results in more output and less shadows.
Brian
I do not know of any thinfilm panels that are anywhere near ready for market. If you hear of any, let me know. I want to work there. If you do decide to go solar you can look at the larger panels used for residential and commercial use. They can be found online and at big box stores (in some areas) for decent prices. You just need to make sure the voltage is correct for a 12 or 24 V system. I have seen my company's residential panels used on boats for over 10 years. I do know that the market is saturated with panels so you have a good chance of barganing the price down. Good luck and post pics when done.
Unfortunately, the big panels for residential are sometimes WAY TOO BIG--at least for my boat . Some of the voltages are inconvenient, too. They might work for those of you with bigger boats. I've been pretty throughly convinced that flexible panels are out for the foreseeable future, but rigid thin film does have some promise for sailboats. Since thin film outperforms crystalline when clouds or shadows are present by a long shot I would think that this would be an attractive option for those who lack unshaded mounting locations and/or sail in overcast areas (i.e., all of us). That said, they aren't going to be powerhouses, but the Team from Germany did win this year's Solar Decathlon (U.S. Department of Energy's Solar Decathlon Home Page) partly because of the thin film panels they used as siding for their house and the overcast weather which is what got me thinking about this whole crazy idea to begin with.
In all my searching, I seem to have come across one thin film panel that *might* be viable. Since it's not listed on its manufacturer's own site, I figure it is either brand new or discontinued . Global Solar Energy may have a rigid, thin film 60W panel 25"x46.5" weighing 20 lbs and a 30W 25"x24.4" weighing 11 lbs. MSRP would seem to be $399 and $199. Compare this to Kyocera and you have roughly the same Watts/$ (first thin film I've found that competes on this and isn't sized for a roof somewhere), but worse on weight and size. Of course, the part that makes me hopeful for future thin film offerings, is that it's backed by a 25 year power warranty, power output supposedly *increases* after exposed to a few days of sun, and they mention sailboats as a potential application. I think I'm going to try and put my solar panel purchase off for a year or two and see if something awesome doesn't come out in the meanwhile. This year's budget can play with wind/water power.
manujosortudo
The problem is that most try to anchor in a less windy place, and water generation adds drag. Solar is the closest we can get to a "free ride" at this time and into thr forseeable future. Why put solar panels on deck where they are liable to be either stepped on or shadowed some of the time? If you use rigid panels and mount them out of the shadow areas at the stern either on a pole mount or on a stern platform or hinged to the pulpit on either side which is probably easiest. Nobody really lacks unshaded areas - you just have to be creative about mounting them. Remember you will sail primarily downwind if offshore passagemaking - this will lessen the apparent wind which will not be great for a wind generator, not to mention the noise. And who wants the drag of a water gen? Trim the sails for the wind and then lose 1/2 a knot or more to gain a few amps? I plan to install rigid panels on either side of the stern pulpit on simple mounts so they can be up for use and folded down if I wish at a dock. With the proper regulator the voltages should not be an issue as the best controllers (MPPT type) will convert wattage to amps and amps to voltage. See this link for the details: Solar Power on Boats | Adrift at Sea
Brian
I understand the limitations of wind, water, and solar power. That's why I'd like to have all three. It true I could get by on just solar, but then I would need a large battery bank to get me through cloudy periods, and/or an insanely large solar array. In the early season here, things are quite cloudy/foggy. If I mix the three, I can take advantage of whatever power source(s) the day's weather offers. Plus, I have limited redundancy if one system fails. This seems to be the most cost/space effective combo for my boat. What's so bad about that?
I find it amusing that you decry the use of wind power while linking to a page that suggests that full time cruisers will probably want a mix of wind and solar power. In my case, the distance from the tack of my genoa to the clew of my main is greater than the length of the deck which leaves little in the way of areas that could arguably be unshaded. Plus the stern is quite crowded and will be very interesting to arrange as is.
As for the noise of wind gens, I can just run them during waking hours if I prefer and on a really windy day, it may only take a few hours for a full charge. Also, I've done my research and am not looking the noisiest models.
As for the water gen, who would pass up such a great source of energy on a passage? I could easily make up my day's energy in just a few hours on a strong run. If I was at hull speed, there would be no speed lost. Plus, I'm not sailing to get somewhere on a schedule, so what's half a knot anyway? (unless the weather window is closing)
In short, every boat and locale is different. For my plans, this kind of arrangement makes sense to me. If I had a different boat in a different place, I might go all solar, who knows? Just because you have a hammer doesn't mean everything is a nail.
Regarding MPPT controllers, I have seen some newer solar panels on the market with voltages as high as 5000V (I think these are for the utility market and too big for my boat anyway). The MPPT's I've seen go up to 240VDC, but I haven't done much controller shopping yet. I agree with you that a MPPT controller would be indispensible to any sailboat solar array that's more than a trickle charger.
My choice would be solar first, possibly followed by wind but not a water gen. I believe I can almost achieve independance from engine running with just solar so that will be the first step. My panels will be rail mounted rigid panels with a MPPT controller, when extended they will be outboard of the hull with an adjustment for angle. At the stern like this they are never shaded by the rig. I don't decry wind so much as see it as a more troublesome in terms of maintenance, moving parts, not to mention a bit dangerous and if solar can do the job it won't be necessary. On my 27' boat without a stern deck aft of the cockpit a wind gen would be in the way I think. Also on a 27' boat a towed gen would probably be too great a hit on speed to make much sense I think.
Brian
"I think it would be a good idea"
. Some of the voltages are inconvenient, too. They might work for those of you with bigger boats. I've been pretty throughly convinced that flexible panels are out for the foreseeable future, but rigid thin film does have some promise for sailboats. Since thin film outperforms crystalline when clouds or shadows are present by a long shot I would think that this would be an attractive option for those who lack unshaded mounting locations and/or sail in overcast areas (i.e., all of us). That said, they aren't going to be powerhouses, but the Team from Germany did win this year's Solar Decathlon (
