Photo: SMA

In search of practical solutions for island networks

What possibilities of sustainable energy supply can be developed for remote areas all over the world? In a research project, the Biberach University of Applied Sciences (HBC) together with the Reutlingen University of Applied Sciences and various partners from industry and science develop island networks and solutions from renewable sources for off-grid areas.

The challenge: PV modules only produce electricity when the sun is shining, wind turbines only when the wind blows sufficiently strong. If they are in full swing under suitable conditions, the surpluses from the generation must be saved or redistributed.

Examples of this already exist, such as the Caribbean island of St. Eustatius or Bonaire, an island in the Netherlands Antilles, which is self-sufficient with renewable energies such as wind or sun and a battery storage system. With the current project “PV-Diesel-Global” the developers around Volker Wachenfeld, professor of grid integration of renewable energies and energy storage at HBC, want to further expand and improve the existing possibilities. In concrete terms, the participants in the research network want to develop hybrid systems that they can link with different producers of electrical energy.

Together with the project partner IEE, biberach University of Applied Sciences will also design a suitable setup for network protection, which enables the stable and economical operation of hybridized island systems even with distributed feed-in. With the decentralization of energy supply by renewable energies, grid protection is already under discussion, but current grid protection solutions are usually based on a one-way load flow from the power plant to the consumer, explains Professor Volker Wachenfeld. The research network wants to limit the problems to be expected for the island network and validate the solutions found. For this purpose, IEE and HBC will set up simulation environments in which modern network protection concepts can be designed and tested with distributed generation. The IEE will focus more on simulation with software tools, while HBC will investigate these simulation results in a realistic environment.

The island networks will be mapped by the Biberach researchers in the Smart Grid laboratory. To this end, the laboratory will initially be upgraded with additional producers in order to meet the specific requirements.

And what remote area could be the geographical basis for the research project? This has not yet been decided, according to the scientist, who describes the ideal picture of the research network for this: a remote supply area, for example an island, where production from wind, sun, possibly also from hydropower, is available in different places and at different times. According to Wachenfeld, this complexity is fundamental to the investigations, “because the energy supply of tomorrow must be decentralized and renewable,” the scientist describes his conviction.