Ronald's solar energy powered microserver


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.

On 23 Aug 2015 I replaced one of the 9Ah batteries with a 55Ah car starter battery, as the two 9Ah batteries obviously are not very good, as can be seen with this typical charge versus voltage behavior in the plot on the right. The moment the charge current kicks in, the voltage rises almost two volts (!) which indicates high internal resistance and therefore a bad battery. 2 Sunny days followed by 4 days of rain...


SwissDutch.ch - Ronald's pagecounter 10068 page views since 28 Sept 2014.

--Apache/2.4.10 (Fedora) PHP/5.5.26 on Ronald's Wandboard Quad, last page update 5 Sept 2015 @ 10:17