Electricity prices are expected to rise by 35 to 40 euros ($50 to $60) per household each year, or less than 5 percent, the government estimates. Though nuclear energy generally costs less than newer options, German law has long stipulated that renewable energy must be purchased first even if it is costlier.

But skeptics consider government assumptions overly optimistic. Stefan Martus, the mayor of Philippsburg, says he believes energy costs could rise more dramatically than government estimates; the price of permits to offset dirty power plants is highly unpredictable and variable, like the value of stocks. And the International Energy Agency does not think Germany — or any other country — will be able to reduce its emissions at a reasonable cost without nuclear power.

Energy agency officials also question predictions that electricity use will decline an additional 10 percent over the next decade given the projected expansion of electric growth of the German economy. The average German family already uses only about half the electricity of its American equivalent.

“Yes, there is German angst about nuclear power,” said Hildegard Cornelius-Gaus, the mayor of Biblis. ”But if you phrased the question, ‘Would you want to phase out nuclear energy if it cost massively more and you risk blackouts?’ the answer would be very different.”

An Ambivalent History

Even before Fukushima, nuclear energy’s days in Germany were numbered. Biblis had been the site of giant national antinuclear demonstrations, and Germany was already enacting a plan for slowly phasing out nuclear energy by 2023. The country had become the world leader in wind power and a master at squeezing more energy efficiency out of appliances and homes, having built tens of thousands of self-heating “passive houses.”

Still, Chancellor Angela Merkel, herself a physicist, decided last fall to extend the operating licenses of Germany’s nuclear plants over concerns that innovation alone would not satisfy the country’s energy appetite.

Fukushima changed everything.

That Japan is a technologically advanced country made the nuclear accident more alarming to the German people than the Chernobyl disaster, at an old Soviet reactor. Despite that, industry experts and residents of reactor towns like Biblis and nearby Philippsburg were stunned by the suddenness of the about-face.