On 27 September 2014 I changed the energy source of the wandboard Quad to Solar panels. I installed 40W of photo-voltaic panels feeding a lead acid battery of 18Ah (2x 9 Ah). The panels come in increments of 20W and I did not think 20W was enough to make it through winter. Note that around this time of year (Sept), the sun is right between minimum and maximum high point. I pointed the panels due south at an angle of 45 degrees.
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