Ulrike protects her eyes with special glasses to watch a solar eclipse in front of the Brandenburg Gate in Berlin. Photo: Getty Images

Power prices in Germany fluttered yesterday as the first eclipse of the emerging solar age passed and utility operators worked overtime to keep the grid supplied.

The moon blocked about 80pc of the sun's light across Europe from about 8am to 11am.

That briefly switched off and then on again thousands of panels that on the brightest days fuel 40pc of Germany's power.

The phenomenon highlighted the variable flows of electricity coming from such renewables as solar and wind. Coping with that intermittency has risen as an issue for grid operators as Chancellor Angela Merkel pressed for cleaner forms of energy to replace nuclear reactors.

"It will be a challenge but we can manage it," Urban Keussen, chief executive officer of the grid company TenneT TSO, said as the skies darkened at an operating station west of Berlin. "We can't ignore the volatile production of renewables. We need to expand and modernise the grids."

Of 89 gigawatt (GW) of installed European solar capacity, Germany has 38.2 GW, which in theory is enough to meet half of its maximum demand.

The initial 15 GW drop in Germany was less than operators had feared. They were able to draw on alternative power sources including coal, gas, biogas, nuclear and hydroelectric energy pumped from storage and were helped by demand reductions from industry.

While there were no reports of power shortages, prices for electricity in wholesale markets both surged and dipped for a time. "It would have been difficult to deal with a situation like today without conventional power plants," Philipp Goetz, consultant at Energy Brainpool.

While eclipses are relatively rare, policymakers are concerned that further expanding renewables will make strains on the grid more routine.

Irish Independent