A third of Germany's energy needs should be met by renewable sources by 2020. This poses a challenge for utilities companies. The energy requires nationwide grids that still haven't been constructed. A building boom beckons.Large coastal wind parks have to be connected to local grids along with smaller wind and solar facilities. The current grids are unsuitable, which means companies like Envia have to invest heavily in electricity pylons, modern electric substations and power networks. MADE IN GERMANY reporter Paula Henfling visits an energy supplier north of Berlin.