Willenhall Energy Storage System


In 2015/16, the UK's largest grid-connected lithium-titanate energy storage facility was  connected to the grid as part of new research led by the University of Sheffield on the growing area of energy storage.

The £4m facility was officially launched on Thursday 17 March 2016 with the announcement of a new innovation project with energy companies E.ON and Uniper looking at future possibilities for large-scale energy storage and how to overcome the challenges associated with connecting such technologies to the grid.

The lithium titanate battery was chosen because it is fast to charge and discharge, has a long lifetime and is arguably safer than alternatives such as lithium ion.

Based at the Willenhall substation near Wolverhampton in the West Midlands, part of the Western Power Distribution Network, the facility is owned and operated by the energy storage research team at the University of Sheffield, in conjunction with partners at Aston University and the University of Southampton.

Professor David Stone, Director of the Centre for Research into Electrical Energy Storage and Applications (CREESA) at the University of Sheffield said: “As the demand for energy increases in the UK, storage systems are needed to balance supply. The first commercial projects are coming on line, but there are still many technical issues to be explored in order to maximise the potential of these technologies and to reduce costs. This dedicated national research facility has been designed to offer enhanced frequency response to peaks in demand and is available to be used by other academic and industrial projects for their research and to test new technologies. I am also delighted to announce a new innovation project with E.ON and Uniper, in which we will be using the facility to help develop their understanding of operating a lithium titanate battery”.

Arne Hauner, Head of Innovation Economics from Uniper said: “E.ON and Uniper will use the Willenhall battery system to provide ancillary services to the electricity network. The reason for doing this is to test the operation of a battery in a new market and to gain operational experience of a different battery storage technology compared to those which we currently operate.”


The University of Sheffield team, with their partners from Aston and Southampton, are already planning the next stage of research including looking at how used electric vehicle battery packs could test the viability for domestic or industrial electricity storage. This ‘second life’ system is due to go online later this year, aiming to combine the energy from the battery packs so that it functions together as a single larger battery unit.

1.  Introduction

The Lithium Titanate Battery Storage System at Willenhall is the largest Grid-connected research driven facility in the UK

The facility is a platform for academia and industry to collaborate and evaluate existing and future grid support methods not possible previously with co-generation methods such as diesel and pumped-hydro

Installed and commissioned in 2015, now facilitating research and advisory services to collaborators

2.  Technology

2 MVA DC to AC ABB inverter system

  • 20 x 100 kVA inverter modules

5 MW Site Capacity

2 MW, 1MWh Toshiba SCiB lithium titanate battery

  • 21,120 2.3V 20Ah cells

Direct connection to 11 kV through transformer

Flexible 100 kVA system for hybrid energy storage

  • EV batteries, flywheels, fuel cells

Live real time data feed at 1 second intervals

  • Transients captured at 40kHz

Multiple data connection types (3G / 4G / 100Mbps fibre) to investigate communication latency challenges

3.  Communications

Measurement granularity down to cell level

Independent control over the battery and inverter

  • Custom Battery Management System (BMS)

4.  Experimental Platform

Fast response 0 to 2 MVA in 40 ms

Custom profiles

Hardware in the Loop Simulation

  • Live Control and Data through VPN

Hybrid Energy Storage

  • 100 kVA System

  • 1 MVA grid-tied lead acid battery also on site

Extensive Laboratory Facilities (CREESA Applied Energy Lab)

  • Battery System Profiling

5.  Opportunities

Grid Support Services

  • Fast and Enhanced Frequency Response (FFR & EFR)

  • Voltage Control

  • Service Layering

Aggregator Evaluation Platform

  • Algorithms

  • Data Connectivity and Latency Issues