Solar eclipse in March 2015 threatens Europe solar grid, temp 'may drop 6 C in 30 minutes'

© Reuters / Goran Tomasevic

A partially eclipsed sun is seen from Juba November 3, 2013

When an almost total solar eclipse starts on March 20, 2015 and casts an umbra on northern Europe, it may face an unprecedented test of its electricity grid due to the massive development of solar power production.

The warning comes from the French power grid RTE, which said Friday that Europe must be prepared for the event.

"The passage of this shadow will considerably reduce photovoltaic power production," Dominique Maillard, the head of RTE, told reporters during its winter outlook presentation, as cited by Reuters."According to our calculations, the impact could be a drop in production of as much as 30,000 megawatts across Europe, it's the equivalent of a six degrees Celsius drop in temperatures in half an hour."

The last time Europe experienced a similar plunge into darkness was in August 1999, long before the Fukushima disaster scare and development of better solar panels led to a boom of photovoltaic electricity. European solar power leader Germany currently has nearly 37,000 MW of installed solar capacity, which accounts for almost 30 percent of domestic consumption. Compared to Germany, France has been slow to adopt the technology, with its total installed solar capacity standing at 5,000 MW - a mere 1 percent of the country's total energy generating capacity.

The danger posed by the eclipse is not so much from lower output from solar panels but rather from the rapid decease and increase, which would happen if the weather on March 20 is good.

"If it's a cloudy day, it will go almost unnoticed. We will only know almost at the last minute, but that doesn't prevent us from getting our contingency plans ready," Reuters reported Maillard as saying.

To prepare the plans RTE wants to coordinate back-up capacity together with other European grid operators.

The eclipse is expected on the morning of March 20, 2015. For roughly an hour, direct sunlight will be blocked over Norway and other northern European states. For roughly an hour and a half, it will be visible in other parts of Europe and North Africa.