Energy storage systems are generally able to compensate the fluctuations in the energy supply caused by renewable energies. For this purpose, however, isolated operation requires very large energy storage systems. This problem can be compensated to a certain extent by the complementary characteristics in wind and solar power generation. So-called WSB-HPS (Wind-Solar-Battery Hybrid-Power-Systems) can significantly reduce the necessary size of the energy storage and improve the power quality.

Concepts for system design can either be developed to achieve one certain goal (for example, system costs) or multiple goals. These goals can include storage size, the quality of the power supply, reducing pollution due to renewable energies and system costs. A number of design criteria must be met. These include in particular

• The consideration of the influence of charging and discharging cycles including their depth on the durability and with that the LCOE and the security capacity as well as its storage contents which is necessary for the power availability.
• Making full use of the complementary properties of power generation through wind and solar energy.
• The consideration of the influence of voltage fluctuations on the grid quality in the power supply operation, which can be caused by wind and solar power.
• The adherence to ramps of substitution of wind and solar power generation by means of power from energy storage in weather- or default-related situations.