Germany’s Association of Energy and Water Industries (BDEW) reports that renewable energy supplied nearly 21 percent of the country’s electricity during the first half of 2011.

Wind, biomass, solar, and hydro power plants generated 57 TWh during the first six months of the year or 20.8 percent of supply, according to the report.

Solar photovoltaic (solar PV) systems on rooftops of home, farms, and factories generated 3.5 percent of national supply, exceeding for the first time the amount of electricity produced by conventional hydroelectric power plants of 3.3 percent.

Wind produced 7.5 percent of German supply, and biomass 5.6 percent.

For comparison, 57 TWh is sufficient to provide nearly 40 percent of California’s electricity consumption during the first six months of 2011.

The press release by BDEW is all the more remarkable because the trade association is led by Hildegard Müller, an ally of Chancellor Angela Merkel and a one-time leading figure in the CDU, Germany’s ruling conservative party. In April 2011, Müller publiclly called on Merkel and the CDU to quit nuclear power no later than 2023, following the Fukishima disaster.

Müller and the BDEW have become increasingly visible in their support for more renewable energy development in Germany.