Hybrid Large-Scale Storage Varel

An increasing proportion of electricity is produced from wind or solar power and thus depends on the weather – rather than on how much electricity businesses and households need at any given time. Nevertheless, the power grid must ensure exact balancing everywhere around the clock. A Battery storage can compensate for short-term frequency fluctuations in the power grid and thus support grid stability. This is a task that was previously performed by conventional large-scale power plants, however the battery storage system can perform this task equally efficiently. Thanks to its unique “hybrid” design, it is also suitable for many other applications and can therefore be used very flexibly. If required, it can supply up to 11.9 megawatts of power to the grid or absorb it from it. Converted, its storage capacity of almost 23 megawatt hours would be enough to supply all households in Varel with electricity for five hours.

The battery storage system in Varel combines two proven technologies: lithium-ion batteries allow rapid access to stored energy and are perfect “sprinters,” while sodium-sulfur batteries are “marathon runners” better suited for longer-term intermediate storage of larger capacities. The advantages of both battery technologies can be combined through intelligent control in such a way that the storage system can stabilize power transport in the regional power grid in the most economical way possible.