Here's the scene in Grisedale near Patterdale on Saturday morning BEFORE the blizzard! Ruthwaite Lodge is a climbing hut that's just above the trees mid-left in this view.
It was snowing by the time we reached it. It was locked but I noticed the solar panel.
I'd estimate the dimensions as 20cm x 15cm, so an area of 0.03 square metres. The intensity of sunlight is given as 1400 Watts per square metre. This would suggest 42 Watts for this panel. However 1400 would be for light hitting the Equator full on, so it will be less here as we are facing the Sun at an acute angle in winter. We have also to allow for the efficiency of the panel in turning sunlight into electrical energy. I found this graph http://en.wikipedia.org/wiki/File:PVeff(rev131111)a.jpg So say we estimate a 30% efficiency, we'll not be getting much over 10 Watts out of this panel on a sunny day. I wonder what it does?
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