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Xort-
The web page thing (can we dissemble here?) isn't a browser problem, it's an email problem. My email client ain't changing and it has the annoying habit of opening links--all in the same window, so it wipes out the one you forgot it opened that was still open, when you open a new one.
Consulting rate? Like I said, what did I get myself into!? It really would be better off with some lab rats who would afford to hang a "standard sun" light fixture over it someplace and do a 16-hour lab run. I'm about at the point where I turn to Tonto and say "Our job here is done" and we ride off with a big HiYo Silver! And Away! Oh, wait, I'm short one big silver horse, one Indian, one black mask and a batch of silver bullets. Drat!
G-
How come you are asking about what the thing does when you already showed up a dozen small ones supplying megawatts of power onboard Giulietta? Obviously, this is a solar powered orange press, it squeezes oranges to make fresh juice. The big panels go up-and-down as they absorb solar radiation, you put the oranges in the big pole in the middle and the juice runs out the spigot in the bottom. That's why the tripod is so big, so you can fit a large bowl or pitcher beneath it to catch all the juice.
Kathleen-
"I suppose it would only require tilts " No, the standard version would require tilts--but also rotation of the pole, to track from east to south (or north) then west. No biggie, but something else to fiddle. Then again, unless you are windcocking into a fixed wind all day every day...you'd have to do that anyway.
And now, a raw data dump followed by some comments. I took one panel and a bag full of controller and wires with me yesterday, slipping the testing in between some more sociable behavior. The raw numbers are (drumroll):
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SolarStik Saturday July 21st.
Results from ONE solar panel.
11AM
13.5V @ 3.1A angled to sun
moved 45d away dropped to
12.5V @ 2.5A
10% loss.
13.4V to 13.3V dropped
2.8A to 2.6A dropped
Shdaowing:
13.5V drops to 13.2V
2.6A drops to 2A (i row) 1.5A (2 rows)
13.3V @ 2.5A out, 33.25 W in full sunlight (no clouds yet)
13.5V @ 2.9A with bumpers removed, all rows unobstructed now.
1/10 A less per bumper.
11:10AM 39.15 Watts /vs/ 33.25 Watts with bumpers left on!
11:45AM light high cirrus clouds
13.6V @ 2.5A aimed to sun
13.3V @ 1.7A misaimed 45degrees
(then)
13.4V @ 2.1A aimed direct
13.3V @ 1.9A aimed 15d off
1:10PM
14.2V @ 3A /vs/ 14.1 C @ 2.7A (42.6 Watts)
14.2V @ 3A direct /vs/ 14.1V @ 2.7A aimed 10deg. off
3PM flat panel 13.6V @ 2.2A
13.8V @ 2.4A when angled to sun.
29.92/vs/33.2Watts, flat is only 90% of full power.
Another 10-15d past the sun produced 13.4V @ 1.9A, bigger loss.
Some high cirrus clouds moving at the time.
Cloud shift, 13.9V @ 2.5V = 34.75W out, angled to sun.
4:30 PM high solid light cloud cover, abandoned tests.
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So, the first big surprise: The panels on the unit that I'm working with, each have three (one inch?) rubber "feet" on them, so the panels don't hit face to face when they are stowed together. As I'm explaining to my friend what the hell I'm scattering on their lawn (and cabling back to the AGM deep cycle in my trunk, what, isn't that how you charge a hybrid?) they note that the bumpers ARE CREATING SHADOW on two of the three rows of cells that are in the BP panel.
It doesn't take long to see that even a little shadow is not a good thing, so I razored the bumpers off and a funny thing happened. As noted, the output rose! Given the sunlight wasn't prefectly even with the wispy high clouds, and that the SolarBoost display rounds things to only 3 digits...I can only say that it appears that any shadowing, even the one inch bumpers that only partly overlay cells, can reduce output by one or two tenths of a volt AND amp.
The best I got today was 42.6 Watts at the 1:10PM run, bumpers off (one mystery corrected) with very light wispy clouds up there. That's substantially closer to the 45W output that BP guarantees, and the 50W maximum. So I think that in full blazing sunlight, 50W output might not be a surprise. (Remember this is from one panel--not the whole array.) But I'm thinking that unless you are in paradise, 35 (40?) Watts is way more realistic for these panels, in the midday hours.
The notes about angling the panels are made without a protractor, using the old Number One Eyeball, so don't expect one-degree precision. They do tell me that there's a significant loss, at any hour, from being as little as 10-15 degrees off from a direct solar angle, and a killer by 45 degrees. Since the sun shifts 15 degrees per hour...Someone shifting their panels just once per hour to track the sun, could be gaining a lot of power versus flat cells. Ten percent times each hour, times the power difference of those hours when the sun is brighter overhead...There's never a mathematician around when you need one.
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