Battery energy storage systems for the electricity grid: UK research facilities

Abstract

Grid-connected battery energy storage systems with fast acting control are a key technology for improving power network stability and increasing the penetration of renewable generation. This paper describes two battery energy storage research facilities connected to the UK electricity grid. Their performance is detailed, along with hardware results, and a number of grid support services are demonstrated, again with results presented. The facility operated by The University of Manchester is rated at 236kVA, 180kWh, and connected to the 400V campus power network, The University of Sheffield operates a 2MVA, 1MWh facility connected to an 11kV distribution network.

Scheduling of grid‐tied battery energy storage system participating in frequency response services and energy arbitrage

“…A 6MW/10MWh lithium-nickel ESS based in Leighton Buzzard provides frequency support, load shifting, peak shaving and arbitrage applications to the grid [15]. In 2013, the UK's first grid-tied lithium-titanate BESS; the Willenhall Energy Storage System (WESS), was installed by the University of Sheffield to enable research on large scale batteries and to create a platform for research into grid ancillary services such as fast frequency response [13], [16]. The emergence of wholesale electricity markets in the UK, together with significant increases in prices, and price volatility of electricity have raised interest in economic opportunities for electrical energy storage [17].…”

Customer-Side SCADA-Assisted Large Battery Operation Optimization for Distribution Feeder Peak Load Shaving

“…The principles of utilizing customer side battery resources for distribution feeder peak load reduction are simple [1], [2]; yet there are several technical challenges that need to be addressed in practice. For example, any arrangement for customer-side battery resources to respond to changes in feeder load would require communications between the customer and the utility's feeder-level supervisory control and data acquisition (SCADA) system.…”

Parameterisation and online states estimation of high-energy lithium-titanate cells

“…wind, solar, tidal) and the trending uptake of smart-grid technologies by distribution network operators (DNOs), such as distributed generation (DG) systems [1], has created instability issues in grid voltage and frequency profiles, often caused by poor reactive power management and lack of load-frequency control in DG systems [1]. As a remedy, large-scale battery energy storage systems (BESSs), ranging from several megawatts [2] to a few tens of megawatts [3], have recently emerged to provide a variety of ancillary services [4] to supplement the grid's power quality around the work.…”

“…In 2013, the University of Sheffield commissioned the first grid-tie lithium-titanate (LTO) BESS in the UK, called Willenhall Energy Storage System (WESS) [2], which consists of 21,120 20-Ah Toshiba LTO cells ( Fig. 1) with a combined power/energy capacity of 2MW/1MWh.…”

“…Now, due to the sheer number of cells involved and the complex BMS requirements for BESS energy/power control and management, it is crucial to have a firm understanding of the behavioural characteristics intrinsic to the utilised cell chemistry. Therefore, with a view to subsequently developing a comprehensive model for the 2MW/1MWh battery storage deployed at WESS [2], this paper reports on the frequency-domain analysis and equivalent-circuit modelling of one of the high-energy 20 Ah LTO cells ( Fig. 1) used in the pack.…”