BayWa r.e. completes unique PV, wind and battery storage system in Germany

BayWa r.e. and Ampt, a company that optimises large-scale photovoltaic (PV) systems, announced the deployment of a combination of wind and solar generation together with battery storage within the microgrid at the Fraunhofer Institute for Chemical Technology (ICT) campus in Pfinztal, Germany.

BayWa r.e. installed three new rooftop arrays and one new ground-mounted system to expand renewable energy utilisation onsite. These PV systems with a total capacity of 690kWp are now connected to the power grid without their own inverters, but via an existing 2MW wind turbine. A 10MWh flow battery energy storage system completes the triad.

Technically sophisticated, it represents a plant combination of wind and solar energy including battery storage, which is said to be unique in Europe in this form.

Leveraging Ampt String Optimisers, each of the different technologies was integrated through a shared DC bus – commonly referred to as a “DC-coupled” architecture. In this way, the generation variability across the PV systems can be managed and the different systems united at a high and fixed voltage to increase system efficiency.

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“We are delighted to bring this milestone project to life. Ampt’s technology simplified a technically very complex project,” said Andrea Grotzke, global director of energy solutions at BayWa r.e. “The way we have added solar to the existing wind energy and battery storage system is unique, and in successfully completing this project we were able to further improve our own expertise and capabilities. We are pleased with the result of this innovative power solution symbiosis and our ability to meet our customer’s individual requirements.” 

The main campus of the Fraunhofer Institute ICT has over 100 laboratories, as well as several pilot plants and three test centres on a 21-hectare site. This project will make a valuable contribution to their increasingly climate-neutral operation.

Ampt String Optimisers are DC/DC converters that perform maximum power point tracking (MPPT) and recover energy losses due to voltage and technology differences. Through individual string MPPT, Ampt optimisers mitigate the energy losses caused by shade from surrounding buildings on the Fraunhofer ICT campus. The optimisers are programmable and provide string-level data, which enhances visibility of the system functions as well as operation and maintenance capabilities.

Levent Gun, CEO of Ampt said, “Combining both rooftop and ground-mounted solar in seven different orientations and two module sizes in one common microgrid with wind power and batteries is a significant challenge. This project is a testament to the capabilities of our industry-leading power conversion technology to simplify control of the diverse systems spread across a site.”

“We look forward to expanding our relationship with BayWa r.e. and continuing to deploy our technology to solve the challenges of our customers in solar and energy storage applications.”

Dr. Frank Henning, institute director of Fraunhofer ICT, added: “It was important for us to add solar to the microgrid that powers our campus, to bring additional flexibility and ensure higher utilisation of our system. Sustainability plays a crucial role for Fraunhofer ICT, and by combining the advantages of wind, solar and storage, we are ensured to meet our sustainability goals and operate in a responsible manner.”