As the weather begins to warm next month there will be just five or six atomic reactors out of 17 still producing power for the German grid, according to the paper cited by daily Bild.
In the wake of Japan's nuclear crisis following the devastating earthquake and tsunami more than three weeks ago, Chancellor Angela Merkel announced that eight ageing reactors would be closed for three months and the government would conduct a review of nuclear policy and safety over the same period.
In addition to suspending operation at the initial eight plants, the government is now also planning to cut capacity at others, Bild reported.
While the country has already had to increase electricity imports from neighbouring countries, shortages could occur, the paper said.
“Short-term deficits can't be ruled out,” the paper reads.
The problem can be overcome, but grid network management must first be improved, the paper continued. Should Germany's grid destabilize, those in other countries would be put in danger too, it said.
Meanwhile daily Die Welt cited another internal document sent from the Federal Network Agency to the Economy Ministry that said the grid had remained stable only because of “favourable weather conditions.”
With little wind and ample sunshine the country's electricity network had not faced any real threat to its stability.
“In the case that the moratorium leads to a long-term shutdown, the test will come with greater use and stronger wind supply in autumn and winter,” the paper said.
It also warned against making rash decisions that could lead to “further uncoordinated steps” affecting the electricity grid.