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Capt. JG

"Mark Borgerson" wrote in message
g...
In article lutions,
lid says...
"Lew Hodgett" wrote in message
...
"JimConlin" wrote:

I'm thinking of a solar panel on my house top which is curved. About
50 watts will be enough.

When it comes to sizing solar panels, it is CYA time.

A reasonable assumption is about 50% output based on location of panel,
clouds, etc, and 50% output/24 hours since it averages 12 hours
daylight
per day over a year.

Thus:

(NamePlate Output)*(50%)*(50%)= 25% NamePlate Output

Factor in an additional 20% derate for what I call the
"StupidityFactor",
thus:

(25% NamePlate Output)*(100%-20 StupidityFactor) = 20%.

IOW, to practice CYA for solar panel requirements, calculate needs
based
on 20% of NamePlate Output.

Lew

We have a system on the house that's rated at 3.4 kwh. The meter
typically
shows 2.90 to 3.2 during the peak hours. I've got 26 panels.

House panels are generally tilted to match the average sun elevation
and are sited to avoid shadows. Boats have masts (even if not
their own) and seldom have the panel tilted properly outside
the tropics. I would expect higher average efficiency for
a household panel.

If you leave the boat unattended for a while you may have to
clean up salt spray and seagull poop when you get back.

Mark Borgerson

I would also. I don't think a curved panel on a roof would help that much,
which was what was asked.

--
"j" ganz @@
www.sailnow.com