From your link:
...The reason for the decline: the balance of power in the solar market has changed. The cheaply-manufacturing competitors from China, such as Yingli, Trina Solar and Suntech go with predatory pricing in the market. The German companies cannot compete with the companies from the Far East because the production costs of German companies are up to 15 percent higher than those of the Asians.
In addition, the German companies made mistakes. For years, they failed to develop new products, but relied on generous government subsidies. But the state cannot and will not afford those subsidies any longer. "Many German companies did not have a clear and viable business model and they relied on too many technologies," says Wolfgang Weger, energy expert at the consulting firm Oliver Wyman...
Not a problem with solar energy, just a shift to conservidiot austerity measures in a time of global economic malaise demonstrating the effect such flawed economic decisions have as they ripple throughout the German (and EU) economies, and demonstrating the weakness of Germany's industrial sector when attempting to compete against a giant like China who is willing to fully underwrite and support fledgling energy industries until they are mature enough to compete and win dominant global market share. More a case of naive business planning on the part of the companies and the German nation (again, as well as the EU in general) rather than any flaw in solar energy concepts. The global solar panel market grew from about 17GW installed in 2010 to about 30GW in 2011, and are currently on track to exceed 45GW in 2012.
Take note, if you want to see America follow Europe into double-dip territory, institute the austerity programs that the tea-baggers are clamoring for.