The FACDS (Flexible AC Distribution Systems) research project, headed by Wiener Netze GmbH, is investigating how network storage systems can be utilized to improve distribution networks. For distribution network operators local storage systems are a new facility that can be put to work flexibly and actively, and regulated dynamically. With these network storage systems numerous options result for network services designed to improve network stability and quality and to ensure a reliable power supply as more power is generated and fed in locally and a large number of new consumers (e.g. electric vehicles) appear on the scene.

Demonstration trial in Aspern, Vienna‘s Urban Lakeside

The pioneering approach is being investigated under real-life conditions in the ASCR (Aspern Smart City Research) testbed in Aspern, Vienna‘s Urban Lakeside. Apart from simulations and laboratory operation, a full-scale network storage system has been implemented, with five battery storage units installed in Aspern‘s smart transformer stations. The system consists of a lithium iron phosphate battery with a power rating of 100 kW and a capacity of 120 kWh, plus an inverter. Here dimensioning storage capacity, and various operating modes in the distribution network, are to be tested.

Strategies for cost-effective operation

How various different stakeholders can use network storage jointly is also being investigated. Apart from utilization by the distribution network operator, the storage system can also help the operators of local facilities to improve their own power consumption; and power providers could store electricity here when wholesale prices are low, and supply it to customers later at the market price.

With suitable strategies for multiple utilization, operating electrochemical storage systems are to become more cost-effective. The key aspect here is using storage capacity and inverter power for network services; only residual potential should be employed to improve cost-benefit ratios. Alongside technological and economic aspects, the project will also spotlight the legal framework applying.