Key facts
- Germany has seen a 40% decline in hop farms since 2006, with climate change cited as a growing concern.
- Farmer Josef Wimmer has installed photovoltaic modules above his hop gardens in Bavaria to provide shade and retain soil moisture.
- The pilot agri-PV system covers five hectares and generates two megawatt peak, with plans for expansion to 20 hectares.
- The system aims to mitigate the effects of rising temperatures and water shortages on hop yields.
- Bureaucratic hurdles, such as long planning permission processes, are hindering the wider adoption of agri-PV.
Hop farmers in Germany are facing significant challenges, including declining prices, reduced beer consumption, and increasingly, the impacts of climate change such as rising temperatures and water shortages. This has led to a substantial decrease in the number of hop farms, with 40 percent closing or switching crops since 2006.
Josef Wimmer, a hop farmer in Bavaria's Hallertau region, the world's largest continuous hop-growing area, is implementing an innovative solution: agri-photovoltaics (agri-PV). He has installed solar panels above his hop gardens, creating a 'solar hat' that provides shade for the hops, which are a shade-loving plant. This system aims to mitigate the effects of climate change by reducing evaporation and retaining soil moisture, crucial for hop growth during dry summer months.
The agri-PV installation was designed by Bernhard Gruber, a former Airbus engineer who now specializes in these systems. The pilot project covers five hectares and has an output of two megawatt peak. Wimmer plans to expand the system to 20 hectares over the next two to three years, with the addition of a one megawatt battery storage system.
While the system shows promise, challenges remain. Wimmer noted that obtaining building permits took nearly two years, and Gruber highlighted that long approval procedures deter many farmers from adopting agri-PV on a larger scale. Initial trials also revealed that excessive shade could lead to reduced hop cone production and lower yields, prompting Gruber to spend two years refining the system's design to balance energy generation with agricultural needs.
Despite these hurdles, Wimmer's pioneering efforts have attracted attention from fellow farmers, local officials, and even government ministers, positioning him as a notable figure in the Hallertau region for his innovative approach to securing the future of hop farming.
