Floating PV on a quarry lake in southern Germany

From pv magazine Spain

Spanish engineer Isigenere has recently completed the installation of a 739 kW floating solar plant in a quarry lake in the municipality of Dettelbach, in the federal state of Bavaria, southern Germany.

According to the company, this is the largest floating solar array built in Bavaria to date. The project has been developed by Isigenere´s client, the German company Climagy GmbH. The facility will supply, with around 700,000 kWh per year, local cement provider Heidelberger Zement. The plant relies on 1,896 solar panels with power of 395 Wp and 3,792 of the company's own floating structures – Isifloating 4.0 – which are based on a patented double-float design and made of plastic commonly used for piping, as well as with UV additives and antioxidants.

Isigenere explains that the electrical distribution of this installation is “unique due to its innovative design, with string inverters installed on floating islands integrated into the structure and mechanically anchored to metal structures which, in turn, save an empty space without floats in their lower part, which offers greater cooling and optimization of returns to investors.”

It also added that direct current power lines are channeled through special clips anchored to the rear of the float, completely avoiding the generation of shadows at any point on the solar panels. An alternating current evacuation is carried out through the maintenance walkways, free of bulky fasteners, which offers the free passage of operators without danger of tripping.

“It takes around three weeks to carry out such an installation,” the company told pv magazine. The anchoring system was provided by Seaflex, a Swedish company that designs and supplies elastic mooring solutions. German installer Rez Kleve was responsible for the plant deployment.

Isigenere specified that its floating technology allows the partial or complete coverage of the water surface to build solar plants on the system that can be located on top of multiple bodies of water: irrigation ponds, industrial-use ponds, reservoirs, hydroelectric plants, water treatment plants, lakes, mines, or even on land susceptible to flooding.

The structures can be deployed with basic tools and equipment and 1 MW of them can be transported in eight 40-foot containers. The manufacturer has an 80 MW annual production capacity and wants to double the figure within four months.