Japanese technology group Hitachi has started up a demonstration energy storage system comprising two battery technologies in Germany.
Hitachi Chemicals has set up the 22.5 megawatt-hour (MWh) lithium-ion and sodium sulfur (NaS) system in Lower Saxony with Japan’s New Energy and Industrial Technology Development Organization (Nedo), Hitachi Power Solutions and battery developer NGK Insulators.
Hitachi said the project combines the advantages of lithium-ion’s “high power charge and discharge output with the long duration capacity of NaS batteries”, to support grid balancing, electric power supply— and establish a business model for power trading through the system in a region where the use of wind power is “accelerating”.
The system comprises 7.5 megawatts /2.5MWh megawatts of lithium-ion batteries and 4MW/20MWh of NaS batteries, in combination with a power grid information and battery control system from Hitachi Power Solutions.
Hitachi said: “Through this system, the four functions of primary control reserve supply, secondary control reserve supply, balancing within a balancing group and reactive power supply to stabilise local grid voltage will be realised to replace the functions of conventional power plants.
Electricity trading for the project— which is backed by Lower Saxony’s ministry for economics, labour and transport— will be conducted in conjunction with German utility EWE’s trading system.
Germany has seen a flurry of investments in battery storage systems in recent months— including a 48MW BESS switched on in the northern state of Schleswig-Holstein— as the country pushes ahead with its energy transition (energiewende) policies.