Emergency Restoration of Power For A Large UK Bank's South West Office

The Challenge

The substation, an end-to-end 4MVA Package Substation, was critical to the office’s operations. It was fed via two cast resin transformers, providing power to essential systems and infrastructure. The sudden loss of this substation not only disrupted business operations but also posed significant risks to data integrity and overall business continuity. With the substation destroyed, there was an urgent need to restore power quickly and safely, minimizing downtime and preventing further losses.

To address the immediate power needs, Johnson & Phillips provided an emergency temporary substation, which was assembled in the office’s undercroft car park. This installation presented numerous challenges, the most significant being severe height restrictions.

The temporary 4000A switchboards required specially manufactured exoskeleton frames to allow horizontal insertion using winches, overcoming a 2-metre height pinch point at the entrance to the car park (as shown below).

Once inserted, the greater challenges included safely returning the switchgear to its vertical state and removing the exoskeleton frames – all while still working within the restricted height of the car park. This process required precise coordination and specialized equipment to ensure the switchgear was safely and securely positioned without compromising the integrity of the system.

A further challenge was presented when it was determined that only one transformer could feed the new substation at a time. To provide the necessary autonomy, an automatic mains changeover panel was urgently required.

Johnson & Phillips designed, assembled, and installed this panel in less than three weeks, even while the project was already underway. This panel provided the critical supply interface for the two temporary 4000A switchboards. Additionally, the installation included active harmonic filters to ensure power quality for the secure banking servers.

The Solution

Johnson & Phillips quickly mobilised an emergency electrical engineer response team specialising in power distribution and substation restoration. The team assessed the damage and devised a plan to restore power as swiftly as possible while ensuring compliance with safety and regulatory standards. The works included full design and method approval, along with all the necessary calculations and safety evaluations.

The entire project, including the specialist lift and shift, installation, and commissioning, was carried out entirely in-house by Johnson & Phillips. This comprehensive approach ensured full control over every aspect of the operation, from the initial design and engineering to the physical installation and final testing.

Key Steps In The Restoration Process Included:

1. Damage Assessment: A thorough inspection of the destroyed 4MVA Package Substation to understand the full extent of the damage and identify the necessary equipment replacements.
2. Rapid Deployment: Sourcing and transporting critical replacement components, including a new power factor correction unit, two cast resin transformers, and associated substation infrastructure, to the site.
3. Temporary Substation Installation: A temporary substation was set up in the office’s undercroft car park. The team tackled significant challenges, such as height restrictions that necessitated the creation of special exoskeleton frames for the 4000A switchboards. These frames enabled the horizontal insertion of the switchboards, which was achieved using winches to navigate the 2-meter height pinch point.
4. Repositioning and Frame Removal: After the switchgear was inserted horizontally, the team faced the challenge of returning it to its vertical state. This delicate operation was performed with careful precision, ensuring the safety of the equipment and the personnel involved. Following this, the exoskeleton frames were meticulously removed, all while still contending with the height restrictions.
5. Automatic Mains Changeover Panel: To address the issue of limited transformer capacity, Johnson & Phillips urgently assembled and installed an automatic mains changeover panel. This panel provided the necessary autonomy by managing the supply interface for the two temporary 4000A switchboards. The inclusion of active harmonic filters ensured high power quality, which is essential for maintaining the integrity of the secure banking servers.
6. Installation and Testing: Expert technicians worked around the clock to install the new equipment, followed by rigorous testing to ensure the system’s integrity and safety before powering up the office.
7. Final Commissioning: The system was brought online in phases to minimise risks and ensure that all components were functioning as expected. The team remained on-site to monitor the system’s performance during the initial hours of operation.