Greg.... Before you order, here's a few additional items to consider. I did not find your original post so forgive me if you have covered some of these already: First, Pascal's comment's are right on. You should estimate how long your frig and other loads run each day and hence how many amp hours hours they use. Then compare that with REAL output amp hours from two solar cells. I'd GUESS you can only replace 10% to 20% of your daily requirement at the 100 amp hour daily load rate. (Don't use that guess, work the actuals.) When I investigated solar panels about seven years ago I gave up on them because of an extremely high cost per amp hour delivered; the higest of any moderate power level delivery alternative; yet they do offer a no/low maintenance alternative to batteries and gennys. As I have posted here before, my conclusion was that solar panels are best use for keeping batteries topped off at a mooring while you are away. I am still awaiting headlines like "Solar panel breakthrough....power triples and cost is cut by 70%..." before placing my own order. Next, if your panel mounting space is limited, consider carefully monocrystalline panels. You'll find them more expensive, but they deliver the highest power per unit of area, very important on the limited spaces of a boat. Your Kyocera panels choice are polycrystalline; hence lower output per unit area. I doubt the advantage of poly has evaporated recently. You also need to consider WHERE you'll be using them. There were department of energy charts previously online that enabled me to estimate ACTUAL daily sun power (irradience) and here in the NE it wasn't impressive. Best exposure/power is at the equator. And a swinging boat at anchor will further reduce your available power. As will rain, clouds, and fog and a rocking boat. If I recall, I could at most expect only about half the manufacturers claimed daily output here in the NE. Power from the sun per square meter is incredibly high, but no one knows how to capture much of it very efficiencty yet. Solar panels are gradually getting more efficient but are not where they need to be for much power. Finally, check out blocking diodes: they are a MUST for solar panel charging systems because in the absence of bright sun your panels will begin to discharge your batteries without some sort of protection device. The diodes permit charge, block discharge, when bright sun disappears. You should consider checking out wind genny's unless the idea/noise/appearance etc is objectionable. They deliver a lot higher amphour/dollar because in nicely breezy areas they'll work 24 hours daily... Good luck!! _________________________________________________________________ Climb to the top of the charts! Play the word scramble challenge with star power. http://club.live.com/star_shuffle.aspx?icid=starshuffle_wlmailtextlink_jan

Thanks for making such a detailed and helpful reply The points you make are truly valid. I plan to use these primarily for summer cruising with a lot of anchoring out I do not presume that these will provide compete power for my fridge and yes they are expensive. Since running my jenny cost me north of $5/hour I expect to get some return on the investment. We have a big battery bank and a big inverter that should store all the amps this can put out. A very traveled owner of the same boat as mine has installed 600W of panels. He has written me that he is very satisfied with them. He does however cruise in the tropics near Singapore where the sunlight is more favorable. If I go to Down Island in the future I will expect to add a wind generator and thus have multiple bases covered. We have lots of space on top of the pilothouse and could probably support 4 or 5 panels of this size. The controller serves the purpose of the blocking diodes. I plan to anchor out a lot this summer so I will let you all know how it turned out. On Feb 6, 2008 8:23 AM, Robin Brueckner <rebrueckner405@hotmail.com> wrote: > > Greg.... > Before you order, here's a few additional items to consider. I did not find > your original post so forgive me if you have covered some of these already: > > First, Pascal's comment's are right on. You should estimate how long your > frig and other loads run each day and hence how many amp hours hours they > use. Then compare that with REAL output amp hours from two solar cells. I'd > GUESS you can only replace 10% to 20% of your daily requirement at the 100 > amp hour daily load rate. (Don't use that guess, work the actuals.) > > When I investigated solar panels about seven years ago I gave up on them > because of an extremely high cost per amp hour delivered; the higest of any > moderate power level delivery alternative; yet they do offer a no/low > maintenance alternative to batteries and gennys. As I have posted here > before, my conclusion was that solar panels are best use for keeping > batteries topped off at a mooring while you are away. I am still awaiting > headlines like "Solar panel breakthrough....power triples and cost is cut by > 70%..." before placing my own order. > > Next, if your panel mounting space is limited, consider carefully > monocrystalline panels. You'll find them more expensive, but they deliver > the highest power per unit of area, very important on the limited spaces of > a boat. Your Kyocera panels choice are polycrystalline; hence lower output > per unit area. I doubt the advantage of poly has evaporated recently. > > You also need to consider WHERE you'll be using them. There were department > of energy charts previously online that enabled me to estimate ACTUAL daily > sun power (irradience) and here in the NE it wasn't impressive. Best > exposure/power is at the equator. And a swinging boat at anchor will > further reduce your available power. As will rain, clouds, and fog and a > rocking boat. If I recall, I could at most expect only about half the > manufacturers claimed daily output here in the NE. > > Power from the sun per square meter is incredibly high, but no one knows > how to capture much of it very efficiencty yet. Solar panels are gradually > getting more efficient but are not where they need to be for much power. > > Finally, check out blocking diodes: they are a MUST for solar panel > charging systems because in the absence of bright sun your panels will begin > to discharge your batteries without some sort of protection device. The > diodes permit charge, block discharge, when bright sun disappears. > > You should consider checking out wind genny's unless the > idea/noise/appearance etc is objectionable. They deliver a lot higher > amphour/dollar because in nicely breezy areas they'll work 24 hours daily... > > Good luck!! > > > > ________________________________ > Climb to the top of the charts! Play the word scramble challenge with star > power. Play now! -- Greg and Susan Han Allegria -- Krogen Whaleback #16