File photo of smoke billowing from the RWE brown coal power plant in Frimmersdorf near Garzweiler open-cast brown coal mine, west of Cologne, December 12, 2013. Germany's shift to renewable energy ... more 
File photo of smoke billowing from the RWE brown coal power plant in Frimmersdorf near Garzweiler open-cast brown coal mine, west of Cologne, December 12, 2013. Germany's shift to renewable energy must be reconciled with the need to integrate it with existing power plants, the chief executive of top German electricity producer RWE said January 21, 2014. REUTERS/Wolfgang Rattay/Files (GERMANY - Tags: ENERGY BUSINESS) less 
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Reuters | Photo By WOLFGANG RATTAY / REUTERS
Tue, Jan 21, 2014 6:33 AM EST