As more wind and solar capacity is integrated into the grid, the portion of low-carbon electricity is rising, but so too are concerns about grid stability. When the wind drops, power production falls, and utilities must act quickly to balance out supplies.
Pumped hydro offers a large-scale solution to energy storage needs, but where this is not available, utilities need an alternative. Hitachi Energy's battery energy storage systems (BESS) offer just that. They enable utilities to respond to unpredictable renewables by balancing power demand and supply, reducing electric surges and sags (voltage drops), and maintaining frequency stability in the network. They also ensure that power remains available for critical loads when outages occur, and even provide enough power to maintain operations until systems can be systematically shut down or backup generation becomes available.
EKZ, one of Switzerland’s largest energy companies and a leading distribution utility, involved with both energy efficiency and renewable energy initiatives, is partnering with HItachi Energy in a pioneering battery-storage project the largest of its kind in Switzerland and the first in Europe. The aim is to enable additional power to be provided to the grid on demand.
To this end, Hitachi Energy supplied and installed a battery storage system using lithium-ion batteries capable of delivering one megawatt of power for a period of 15 minutes. A MicroSCADA (supervisory control and data acquisition) system is used to control and supervise the battery management system, as well as the converter and system optimizer though which the system feeds power into the grid. The storage facility will be integrated into EKZ’s power distribution network and evaluated in key functions such as balancing peak loads with intermittent power supplies, and grid optimization.
Hitachi Energy provided the entire BESS for EKZ, comprising 432 battery modules (accommodated in a 45-foot outdoor container), a converter to transform direct current (DC) to alternating current (AC), and vice versa, and the MicroSCADA system to control the grid interface. An RTU211 was built-in to integrate low-voltage switch gears and to supervise auxiliary systems, such as the battery container and the uninterruptible power supply, as well as collect data for overall monitoring and control purposes.