Energy storage in the low voltage grid for TAURON Dystrybucja

Apator SA, in cooperation with TAURON Dystrybucja SA, has launched an energy storage facility designed to stabilise the operating parameters of the low voltage distribution network. This is yet another project carried out for domestic Distribution System Operators, who are seeking effective technical solutions to balance the grid and achieve reduction of excessive loads during peaks in energy production from Renewable Energy Sources.

As new RES sources are connected to the system, the importance of energy storage facilities in the local balancing of electricity networks is growing. The storage facility, commissioned at the end of 2023 by Apator SA for TAURON Dystrybucja SA, with a power of 50 kW and a nominal storage capacity of 16 kWh, performs basic features related to improving the operational parameters of the distribution network – it enables the symmetrisation and stabilisation of the grid voltage at the storage facility’s connection point. A dedicated energy management system (EMS) optimises battery operation, whilst the two-stage converter used has an application that allows independent control of active and reactive power flows for each phase of the supply voltage. Furthermore, the storage facility has been connected to the operator’s SCADA system, enabling full remote and digitally secure control of the equipment.

Safety and efficient operation of the storage facility

A novelty in this project was the application of used lithium-titanium traction batteries as energy storage units. Batteries of this type can be successfully utilised in stationary energy storage systems after their operational life, naturally following a proper service inspection. Extending the service life of the batteries by giving them a ‘second life’ fits perfectly with the concept of the Circular Economy. The solution meets strictly defined standards and technical requirements, whilst minimising the negative environmental impact generated during the initial battery production process and subsequently during their recycling.

To ensure the safe and effective continued operation of the batteries, the necessary technical analyses were carried out and the parameters of individual cells were measured. In the next step, the battery bank was equipped with a new automatic technical control system (known as BMS) dedicated to the battery’s new operating mode and integrated with the master EMS system and the operator-side control and supervison systems. In addition to the LTO battery bank with a nominal capacity of 16 kWh and the BMS and automatic storage control and management systems, the solution was equipped with a two-stage, bidirectional AC/DC/DC converter manufactured using silicon carbide technology with a power rating of 50 kW, an HVAC (heating and air conditioning) system, a fire protection system and an alarm system.

Apator is expanding its range of energy storage solutions for Distribution System Operators to stabilise the operation of low-voltage grids, particularly those with a high proportion of RES. The solutions developed and implemented support operators in effectively managing grid operations and ensuring the reliability and continuity of electricity supply. Given the changing structure of energy generation in Poland, where we have an increasing number of Renewable Energy Sources, energy storage will become an essential tool for the energy transition and an increasingly common feature of our national landscape.