effectiveness of solar & wind

[camaraderie]

I for one discount Cjoe's explanation of Kuwait and 16 hours as he was relating a second hand explanation and has limited electrical background so I am prepared to just chalk that up to a misunderstanding on his part and not some sort of slam on solae stik. Brians explanation that the Kuwait performance is based on the clarity of the atmosphere at low angles of the sun deserves more scrutiny since it is his first hand account but we have no details of the test other than the claimed output. Again..I will wait for the ps test as at least that will give us a standardized method and results which we then can dissect.

[sailingdog]

sounds good to me. I plan on keeping an eye on the other thread to see if Brian responds directly.

[xort]

any clues as to when this PS review is due out? The magazine and website both give listings of upcoming tests and no mention of the stik

[sailingdog]

Xort-

Might be a while, as testing something like the SolarStik is probably something that will take a bit of time to do a proper and thorough test.

[camaraderie]

No clue...I wrote the editor but no response.

[hellosailor]

Cam-
"Brians explanation that the Kuwait performance is based on the clarity of the atmosphere at low angles of the sun "
Clarity of the atmosphere? The standard panel ratings are based on a "perfect" atmospheric clarity. Invoking a better atmosphere is not possible on this planet. "low angles of the sun" ? Again, no. When the sun is at low angles, sunlight has to pass through MORE atmosphere than it does at midday, again, less light falls on the panel than it does under the rating conditions.
So it comes back to a 100-W rated panel producing 100 Watts under optimal conditions. That's 7.24A at 13.8V, the lowest voltage I would call a "charge".
If you could get noon daylight for ten hours, sure, that would produce 72 amp hours of charging power.

Which is forcing me to find out things like "The amount of light received on a sunny day during July and August is about 130 to 160 kilolux". Okay, now we can quantify the amount of light, let's say 150KiloLux (KLux) which means about 150,000 foot-candles of brightness and that morphs into "KiloLux-Hours" when you measure it over time.

So if the noon sun is 150,000 foot-candles in brightness and we can get some similar numbers for other times of the day, we can apply some numbers to this. With extensive searching I came upon "Annual totals were 108, 124 and 122 megalux hours for 1947, 1948 and 1949 respectively with 116 as the mean of the whole series. " referring to Plymouth, England.

So, ignoring global dimming (which has been real) let's say 120 mega-lux-hours in one year, spread on 365 days. That makes a little under 328,800 kilo-lux-hours in any one average day in Plymouth, where the length of the day will vary quite a bit. But--as an average over the year--that's only a bit more than two full "noon hours" of sunlight in a day. Perhaps the total for a summer day is twice as much, i.e. four hours of the noon sunlight rating?

Does any of that sound good enough for some quick late-night back-of-the-envelope sloppy web research? (And I earnestly invite anyone who can, to seek better numbers. Seems like most of the research about sunlight is in scholarly journals that are sold, not simply published on the web.)

[SimonV]

If I feed by hamster 50% more grain (food = fuel = energy) he should spin his wheel 25% faster, not 50% because we always lose something through inefficiency. But my hamster wants to just sleep.
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[camaraderie]

HS...in theory the Klux stuff is fine but we also need to know what amount of sunlight energy drives full output from these panel cells...if it is LESS than "full direct noon" then you need to calculate how much lower the angle of the sun must be before output begins to drop etc. which I think is a deep hole akin to proving how many angels are on the head of a pin. I think I'll just stick with the basic ohm's law stuff...out of the Kuwaiti dessert and on a sailboat at anchor somewhere below the tropic of cancer for a real world scenario for boaters likely to purchase panels.
Looks like they're gonna start there own 500 post thread over at SBO ...things are heating up.

[wind_magic]

Dude I think there is something wrong with that hamster.

[wind_magic]

What happens is that there are these panels that have crystals in them that are dark colors. And see the golden sun shines down on the panels, and those crystals they become happy, and warm from all the sunshine. And then they start to smile a lot and the whole panel starts to pump electricity through the wires that are hooked to it, like a heart you know that is excited about being alive. The more sunlight there is the happier the panel is and the more it wants to spread happiness around so it talks to it's friend Mr. Battery bank through the wires and then the battery bank gets happy too, even though it is hidden down inside the boat and doesn't have any sunshine on it. Just the stories about the sunshine makes it happy, and the solar panels are pumping sunshine down to it through the wires too so the batteries drink it up and gets good feelings. And if you have a wind generator it really gets excited about the wind and it's blades whirl around and sing and it talks to the batteries too and tells them about the wind. Then the batteries get even more happy! It's all very technical.