Tesla installed another major battery energy storage system - this time in Europe (Terhills, Belgium) - that consists of 140 Powerpack units.
Tesla Powerpacks Balancing the Grid in Terhills, Belgium
The ESS is rated for 18.2 MW of power, but Tesla didn't stated the number of MWh of energy (we could assume up to 28 MWh, if 200 kWh per Powerpack).
The main purpose of that system is balancing the grid to maintain the nominal frequency of 50 Hz (the U.S. frequency is 60 Hz).
According to Tesla, reaction time for battery energy storage is 100 times faster than the power plants.