Spiegel reports:

This week, two of Germany's most important solar energy projects came online -- the second biggest solar power project in the world and one of the first solar thermal "power towers." The projects are part of the country's plan to provide 20 percent of its energy through renewable sources.

Officials flicked on the switch at two of Germany's most important new solar energy sites on Thursday. In the eastern state of Brandenburg, the world's second-largest solar energy project went online. And halfway across the country, in North Rhine-Westphalia, a smaller scale but perhaps equally important facility launched -- Germany's first solar-thermal power plant.

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