Juergen Silberzahn, mayor of Wolpertshausen, poses in front of a biogas generator in the village of Wolpertshausen near Schwaebisch Hall, Germany, March 18, 2016. Wolpertshausen produces up to 30 percent more electricity from renewable sources (biogas generator, wind turbines and solar panels on the roofs) than its 1,300 residents use. Picture taken March 18, 2016. REUTERS/Michaela Rehle