Germany's Green party said on Monday that shuttering the 20 dirtiest coal-fired power plants would be a condition for joining a coalition with Chancellor Angela Merkel's conservatives after this month's election.

In a position paper published Monday, the Green party said it would fight for "a new federal government with Green participation to decide immediately after the election a decision to exit coal with a concrete timetable and as the first step take the 20 dirtiest coal-fired power plants off the grid."

Polls show Merkel's conservatives winning 38 percent of the vote in the September 24 election but she will need to form a coalition to govern.  Under current poll trends, that means the conservatives will have to form another "Grand coalition” with the Social Democrats or a so-called "Jamaica coalition” with the Greens and Free Democrats (FDP).

Read: Greens slip to 8.4 percent in latest election poll 

Both the Greens and FDP have raised questions about the prospects of such an alliance, with the leaders of both parties recently calling such a coalition a "fantasy." One of the main clashing points between the two parties is over immigration policy.

Greens co-leader Cem Özdemir said Monday in Berlin onboard a solar-powered boat that they planned to sail past the chancellery office that "we will talk to everybody but not about everything."

Read: Germany's political parties: CDU, CSU, SPD, AfD, FDP, Left Party and Greens 

The redline on lignite-powered power plants comes as last week a study said Germany was on target to miss its 2020 target to cut greenhouse gas emissions by 40 percent compared to 1990 levels. Germany's CO2 emissions have risen slightly over the past eight years. 

"Instead of being world champions in climate protection, we are world champions in lignite coal," Ozdemir said, calling for a second "energy transition" to wind, solar and biomass. Germany's

By 2030, the Greens want 100 percent of power to come from renewable energy. Renewables covered around a third of Europe's largest economy's electricity consumption last year.

Read: European climate protesters take on German coal

Once championed as the "climate chancellor" for pressing other wealthy countries to reduce greenhouse gas emissions, Merkel's reputation has been undermined by the slow pace of reducing coal reliance as the country phases out nuclear power.

Merkel has said that Germany should eventually phase out coal-fired power plants, but the potential economic impact on Germany's coal-mining regions have so far prevented politicians from committing to a deadline for giving up on dirty coal.

cw/xx (AFP, Reuters)