It's crucial for sailors to know the difference between performance of the two basic types of solar panel construction: 1) crystalline (mono and poly, difference not relevant here) 2) amorphous Crystalline are made up of many individual crystal-based cells wired together. Usually you can see this just by looking at the panel. Amorphous are made by depositing continuous thin films of the PV material. They are clearly different when looked at - a relatively solid color. You may see a few large areas of material that are distinct, but they will not have the dozens and dozens of individual cells as on a crystalline, nor the obvious 'crystal' looking surface. Crystalline generate the same amount of power in less surface area. In other words, amorphous needs more surface area to generate the same power. So if space is a premium, it would seem that crystalline would be better... HOWEVER - this is the biggie for sailboat installations - amorphous will suffer considerably less power output loss from shading. Shading even a very small area on a crystalline panel will cause major reduction in power output. If you are lucky you will only lose 50%; if not, you will lose 75-90% (depending on where/how the shadow falls on the panel). With amorphous, shadows affect the output much less - it's more proportional to how much of the panel is shaded. A small shadow in one area on amorphous will only cost you a small amount of power output. So if you can't mount clear of shadows, you may do better overall with amorphous. Historically most flexible panels are amorphous. However there are now some "bendable" panels that are crystalline, for example: http://www.directron.com/rng100db.html And not all amorphous panels are flexible - Unisolar made both rigid frame and flexible amorphous panels. Google flexible amorphous pv panel ...and you'll get tons of info & sources. Also re charge controllers, the cheap ones that come with portable kits and the like will last a while in freshwater, but for saltwater they will die quickly from internal corrosion. My recommended charge controller for small boat PV (up to 7A) is the FlexCharge PV7D: http://www.flexcharge.com/PV7D.html For up to 25A, and from multiple sources if you have them (PV, wind gen, motor gen) the NC25A is the ticket: http://www.flexcharge.com/NC25A-Product-Info.html Both are completely sealed (resin potted), marine/rugged environment ready. FlexCharge has a patented charging algorithm that is better for your batteries, and more efficient, than any other method. You get more juice from your panel to your battery with less stress on battery. Designed and made in USA no less (imagine that!). My recommended source is John Drake at http:solarseller.com. His web site is a bit of an archaic mess, here is the page for the PV7D: http://solarseller.com/seelye_ses_flexcharge_charge_controllers_controller.h... Here is the page for the NC25A: http://solarseller.com/flexcharge_wind_hydro_solar_charge_controllers.htm I don't make any kickbacks from this...:-) Just sharing my years of experience doing off-grid land, and marine, solar power installations, fixes, upgrades. cheers, John S. On 02/05/2015 06:31 AM, Bill Wickett wrote:
Makin' Time is under the winter tarp, with a snow topping to boot, so not accessible
Can anyone provide the hatch covers sizes for the companionway and forward hatches? Boat is a 2003 model, built by Bob Eeg.
I am looking at mounting a flexible solar panel on one or the other. Probably the forward one, less shadow from the boom or sail.
Thanks if you can provide this info, or any experience you have had with mounting or using solar panels.
Bill
-- John Schinnerer - M.A., Whole Systems Design -------------------------------------------- - Eco-Living - Whole Systems Design Services People - Place - Learning - Integration john@eco-living.net - 510.982.1334 http://eco-living.net http://sociocracyconsulting.com