A HYBRID POWER PLANT AND A METHOD FOR CONTROLLING A HYBRID POWER PLANT

The invention relates to a hybrid power plant for producing power to the electrical grid, the hybrid power plant comprising a plurality of energy assets; a first renewable power generating unit, such as wind turbine generators, and an energy storage unit, preferably a battery energy storage system. The hybrid power plant has a power plant controller arranged to communicate with the plurality of energy assets, and, when an under-frequency event occurs, the energy storage unit provides frequency support during the under-frequency event by providing additional power as a function of a state of charge of the energy storage unit at the time when the under-frequency event occurs. Thus, during an under-frequency event, it is possible to obtain a more stable power output from the hybrid power plant.