A landmark for renewable energy

Siemens delivers transformer for the world’s largest battery storage installation. Energy generated by the Hornsdale Wind Farm in South-Australia can be fed in exactly when it is needed – thanks to world renowned e-car manufacturer’s grid scale lithium-ion battery installation and Siemens’ generator step-up transformer (GSU).

Storing volatile wind power

Southern Australia has lots of wind during windy hours and lots of sun during sunny hours. However, when neither wind nor sun is available the grid lacks energy and the grid operator has to re-dispatch generation capacity to keep his grid stable. In the face of these difficult circumstances, the local authorities and the operator had to find a solution for their new wind farm in Hornsdale.


And they did. The South Australian Government and the Australian Energy Market Operator (AEMO) in concert with Neoen, a renewable energy company and operator of the 309 Megawatt (MW) windfarm decided to invest in a grid scale battery storage solution.

Hornsdale power reserve

The renowned pioneer of electric cars made it happen. They set up a massive power reserve nearby the wind farm. At 100 MW and 129 Megawatt hours (MWh) it is the world’s largest lithium-ion battery installation. Thanks to its fast ramping capability it can dispatch large amounts of power quickly and reliably. 


In December, 2017, for the first time, clean and affordable wind energy could be stored and dispatched to the grid 24 hours a day, 7 days a week, whether the wind is blowing or not, always maintaining grid stability – thanks to Siemens’ generator step-up transformer (GSU). 


Generator step-up transformers are the critical link between storage and the transmission network. Before the energy can be fed into the grid, it must be transformed – in this case from 33 Kilovolt (kV) to 275 kV. This is done at the local substation by a 120 Megavolt-ampere (MVA) transformer. 

Meeting challenging time schedule

“We met the challenging project schedule through close co-engineering with the customer based on existing, supply optimized standardized design elements“, says Beatrix Natter, CEO of Siemens Transformers. 


With the commissioning and inauguration of the project, South Australia has a system that responds faster than coal-fired back ups. Therefore, the wind power reserve massively improves system stability, smoothing out fluctuations, avoiding major outages, and providing affordable renewable energy to its consumers.