Canary Wharf

Citigroup European Headquarters

This 1.2 million ft2 facility consolidates UK and European operations for Citigroup, the world’s largest financial institution. Our project scope included a 30,000 ft2 server farm/computer centre and 42 floors of communications technology rooms, supported by six 1600 kW rotary diesel UPS units for 9.6 MW of back up power to critical operations. At the time of construction, Citigroup Tower was the third tallest building in the UK.

Rotary diesel UPS units were arranged in four systems to provide dual redundant power to critical loads, using a highly fault-tolerant distribution scheme through to the raised floor Power Distribution Units and tech rooms. A sophisticated dual redundant load management system provides for control of all critical and essential loads under all normal operating and failure mode conditions. The design was configured to expand by two more 1600 kW units, for an ultimate load capability of 12.8 MW.

The control system also permits operation of all international office functions when all diesel UPS systems are available following a utility power failure via sequenced load stepping, allowing for a “business as usual” operating scenario even under widespread utility outages.

Electrical Engineering | Communications Design

Size: 1.2 million ft2 | Status: Completed 2001

London, United Kingdom

Complex and highly resilient MEP design | Fly wheel energy storage UPS systems | Load design expanded by two 1600 kW units, for an ultimate load capacity of 12.8 MW | Rotary diesel UPS units arranged in four systems to provide dual redundant power to critical loads