James Cook wrote:
> One of the most important things to remember is to make sure that the
> panel is mounted on an adjustable frame so as to maximise the 'impact'
> of the sun's rays. Some have calculated that laying the panel flat
> reduces the output, which is NEVER that great, by as much as 60%. The
> lumpy water boys and girls are finding this out to there cost as many
> blue sea sailors have bought the very costly stick on, flexible panels
> and are very disappointed.

<scientist hat on>
Could probably more than that...
The suns rays are more or less parallel, therefore as the panel is tilted so 
less sun hits the panel.  If we have the panel at 90deg to the sun then we 
get max power, if it's at 0deg (i.e. edge on) then we get zero power - so 
just look up sine tables and x 100 to get a %age
http://www.mathnstuff.com/math/spoken/here/2class/330/sincost.htm
Sine 90 is 1 (100%) Sine 0 is 0 (zero)
Panels at, say, 60deg / 45deg / 30deg give results of 86.6% / 71.9% / 50%.
This is theory - note that the panel has a transparent covering - at the 
lower angles, it's going to start to act like a mirror and reflect the sun 
away, so the lower figures above will be even more worse, than compared to 
the high ones - one may find that at 10deg it's all reflection and no 
absorption.  So flat on top of the boat in the winter is naff all use.

Easy when you know how.

Ron Jones
Process Safety & Development Specialist
Don't repeat history, unreported chemical lab/plant near misses at
http://www.crhf.org.uk Only two things are certain: The universe and
human stupidity; and I'm not certain about the universe. ~ Albert
Einstein 


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