Europe power grid system was put to the test by the recent solar eclipse that swept the continent. The solar power installed base generates over 89GW, of which more than half is sourced by Germany with a capacity of 39GW. The German grid operators managed the rapid transition from full power to a low level caused by the eclipse and back to normal levels by rebalancing the power system using traditional power sources and reserves. Overall the European grid was back to normal without any issues. This event though is warning us the solar power system has a major weakness.  If an event causes a significant reduction in solar exposure, the power grid relying on this type of source will be affected severely. For instance, a massive volcanic eruption could cloud vast areas of land for a long time.  Solar power is an excellent source of energy, but it needs a good backup plan. Europe’s Power Grid Passes Eclipse Test; No problem meeting electricity demand, despite large amount of solar capacity.