Thamesgate has supplied an inert gas fire suppression and H2 gas detection system for Europe’s largest lithium-ion battery storage project in Leighton Buzzard, Bedfordshire, announced the company. The fully automated Smarter Network Storage (SNS) project is a 6MW/10MWh battery substation that was commissioned in December 2014. S&C Electric Europe enlisted the services of Thamesgate to design, install and commission the fire suppression system. Thamesgate had previously worked with S&C on another major battery storage installation in Scotland and was chosen to supply the fire suppression and detection system at Leighton Buzzard.

The system installed at Leighton Buzzard comprises two conventional IG55 (Argon/Nitrogen) inert gas fire suppression controllers connected to smoke and hydrogen smoke detectors. The detection system comprises two VESDA (Very Early Smoke Detection Apparatus) detectors configured to provide detection for the “double-knock” arrangement of the fire suppression system. This provides an automatic fire detection and alarm system that is capable of identifying when two elements actuate simultaneously within the same zone or area.

H2 gas detection samples the return air of the highest sampling pipe (SCADA alarm only) while primary smoke detection utilising VESDA smoke detectors covers the return air plenums of the cooling systems (independent of the fire suppression system) to provide advance warning of a fire incident. The system also included multiple entry points using 10 lamp status units with the facility to change mode and check gas release, discharge pressure switches, and gas release call points and hold off switches located at the exit doors.

For the dual inert gas fire suppression cylinders, both systems connect to a main/reserve bank of IG55 fire suppression cylinders with both main and reserve banks being sized to the largest protected volume. In-line non-return valves control the number of cylinders being released based on the area activated while a fully manual isolation facility controls mechanical isolation of the actuation lines of the fire suppression system. Main or reserve cylinders can also be selected manually.

A total of 76 cylinders – 80 litre, 60 bar regulated pressure outlet, 300 bar – were installed with 48 cylinders for the battery room itself configured in three rows of 15 plus three cylinders making a fourth row. These feature cascade pressure relief for over-pressurisation venting and non-return pressure relief vents that allow pressure to accumulate within the cylinder room to be extracted via the main ventilation ducts.

The building alarm fully monitors the status of each fire suppression system showing any fire and fault conditions and all fire suppression cylinders are monitored for low pressure. Master reset and master silence signals are provided for all subsystems.

Nick Watkins, managing director of Thamesgate Group, commented, “This project was a demanding challenge for our engineering teams being sited in two buildings with the main alarm panel remote from the gas bottles necessitating a pilot gas bottle in the reception area using fine copper tubing. Also, as commonly encountered in such large installations, there were significant changes to the specification as the project evolved to the extent that the final implementation looked very different to the original system envisaged.”

The installation also had to meet numerous BS and EN standards including BS6266:2011 (Fire protection for electronic equipment installations), BS7273 parts 1 & 2 (Code of practice for the operation of fire protection measures), EN 15004 parts 1 and 9 (Fixed firefighting systems – gas extinguishing systems), BAFE SP203-3 (Fixed gaseous fire suppression systems) and the FIA code of practice for air sampling systems.

“The Leighton Buzzard project showcases Thamesgate’s multi-skilled approach to solving customer problems and servicing the power installation and protection market,” concluded Watkins.