That's not ironic. A coalition government — something American readers may not be too familiar with — governs with a set of agreed upon policies decided during the formative stages by the participating parties. By necessity, those policies will differ from what the individual parties would want were they to rule alone, but represent instead a compromise.
So a coalition government where greener parties represent 50% of the governing coalition would likely be greener than one where they only have 25%, but to do everything according to their own party programme they would need to have a majority vote to be able to govern without forming a coalition.
Sometimes participating in a coalition government means the government takes actions the individual party may not find desirable, but they accept these because they do get to have their say on other topics. And sometimes local branches of a party have a differing opinion on some topics.
This is overall a good system though. It means you can vote for a party closest to your ideals, and even have a chance that they can govern (e.g., as part of a coalition), or at least have them represented in parliament.
The real irony is that a Green Party is opening new coal mines because Gerhard Schröder, former leader of the SPD, allied of the Green in this government, and former German chancellor lobbied for Gazprom and because Die Grünen lobbied to shutdown nuclear plants after Fukushima.
So a coalition government where greener parties represent 50% of the governing coalition would likely be greener than one where they only have 25%, but to do everything according to their own party programme they would need to have a majority vote to be able to govern without forming a coalition.
Sometimes participating in a coalition government means the government takes actions the individual party may not find desirable, but they accept these because they do get to have their say on other topics. And sometimes local branches of a party have a differing opinion on some topics.
This is overall a good system though. It means you can vote for a party closest to your ideals, and even have a chance that they can govern (e.g., as part of a coalition), or at least have them represented in parliament.