Can Germany phase out coal power?

But privately, Hendricks may have had to answer some awkward questions.

Yes, Germany increased its renewable share of electricity consumption between 2004 and 2013 from 9.4 percent to 25.6 percent. The share of total energy consumption is around 11 percent.

But despite the increase in solar and wind power, Germany is likely to miss its 2020 target to reduce its greenhouse gas emissions by 40 percent.

"In reducing our greenhouse gases, we are not as successful as we are with the increase in renewable energy," said Gerd Rosenkranz, senior associate at German think-tank Agora Energiewende, named after Germany's energy transition process.

Rosenkranz spoke to journalists at a recent seminar organised by Clean Energy Wire, a non-profit group. Both institutions are funded by the two same foundations: Mercator and the European Climate Foundation.

In January, Agora Energiewende published a plan to end coal power generation in 2040. Coal is the most polluting of the fossil fuels.

"Ultimately, there is no alternative to the phasing out of coal power if Germany is to fulfil its climate goals," the report said.

The report came just months after the UK announced the end of coal-fired power plants by 2025 (unless the experimental carbon capture and storage technique can be applied).

About 24 percent of Germany's total energy consumption comes from brown coal and hard coal.

But the political focus of the Energiewende, or energy transition, had always been more on getting rid of nuclear power than on reducing carbon emissions.

Some trace Germany's anti-nuclear power sentiment back to World War II, and to the strong post-war opposition against producing nuclear weapons.

But it took the political elite a while to catch up with the anti-nuclear power activists, whom Helmut Kohl in the late 1970s called "reactionaries".

"They are opposed to progress," said the centre-right politician, who later spent 16 years as chancellor.

The 1986 accident at the Chernobyl nuclear power plant strengthened the anti-nuclear movement, some members of whom later went on to gain positions of power in the centre-left/left coalition government of chancellor Gerhard Schroeder. In 2000, his government announced it would phase out nuclear energy.

For a brief period after Angela Merkel took over as chancellor, the nuclear phase-out seemed in danger. Her centre-right government tried to extend the life of some nuclear power plants.

"Then came Fukushima," said Rosenkranz, referring to the Japanese nuclear accident in 2011.

"It became clear that a party with a pro-nuclear attitude could never win a German election again. The first one who understood this was Angela Merkel."

Merkel immediately shut down eight nuclear power plants and set the final date for complete phase-out at 2022.

The second phase-out was supported by 85 percent of MPs in a vote in 2011.

"The fifteen percent who did not support it wanted a faster Energiewende, and not a slower one. All parties wanted the nuclear phase-out," said Rosenkranz.

Of course, Germany needed alternatives for the nuclear power plants that were being shut down.

It embraced solar and wind power.

Between 2004 and 2013, Germany increased its share of green electricity consumption from 9.4 percent to 25.6 percent.

But while in other European nations an increase of "renewables" usually correlates with a decrease in greenhouse gas emissions, Germany's annual volume of carbon emissions increased in 2012 and 2013, as coal production replaced some of the reduced nuclear power.

In 2014, Germany had reduced emissions by 26 percent, compared with 1990 levels. But it is unlikely that the 40 percent reduction target by 2020 will be met.

Figures for 2015 are not yet available.

Rosenkranz said the Paris agreement meant Germany needed to step up its game.

"There is pressure that Germany loses its credibility if it continues to burn coal," he noted.

The question is, can Germany achieve a policy for a coal phase-out? There are positive and negative signs.

According to Rosenkranz, the nuclear phase-out was successful because a political consensus became possible after Fukushima.

So does Germany need a climate-related disaster on the scale of Fukushima to generate the necessary political will for a coal phase-out?

"I don't hope so," the German researcher said.

It is hard to imagine the kind of event that might have the same impact as Fukushima.

But Rosenkranz offered one example of a climate-related disaster that almost had a similar impact. After Hurricane Katrina hit the US city of New Orleans in 2005, US authorities said that if such a disaster happened again, it would consider abandoning the city, Rosenkranz said.

"That would be [a climate] Fukushima," he said.

However, the consequences of a nuclear disaster are much more direct than continued emissions of greenhouse gases via coal-fired power plant

Calls for masterplans

German sociologist Dieter Rucht points to another problem. He says anti-nuclear activists have a more "clear focus".

"You have these huge plants, or at least on paper the design of these plants. You can see them," he said.

"We have a limited number of actors whom you can address, whom you can criticise."

But answering the question which disasters are directly caused by climate change, and who is responsible for climate change, is much more complex.

Meanwhile, the Agora Energiewende plan has been met with mixed responses from German ministers.

Sigmar Gabriel, vice-chancellor and responsible for energy, said he had become "somewhat careful with these calls for masterplans".

"I think it is a bit too ambitious to want to exactly describe in 2016 the energy situation of 2050," noted the centre-left minister at a conference in January.

Environment minister Hendricks, however, is in favour of a coal phase-out. She has not committed to a date, but said according to Reuters that the Agora Energiewende report (which named 2040 as coal-exit year) was "helpful".

Rosenkranz said: "When a year and a half ago someone would have said: in one and a half year from now, we will discuss in Germany a coal phase-out like we have discussed a nuclear phase-out I would have said: Never ever. That is going to take another 10 years."

He draws hope from a recent poll, which asked German citizens what was their preferred source of power.

Most wanted solar power (80 percent), while 76 percent also wanted wind power as part of the mix.

At the other end of the poll, eight percent said they wanted nuclear. Just five percent said coal.