UCLH Generator Replacement

The project involved the replacement of the existing FG Wilson Generator with a new 1200kW/1500kVA generator and associated infrastructure at the NHNN. This included the installation of new fuel pumps, day tank, generator switchboards, power and signal cabling, cable containment, and testing and commissioning of the new systems. Additionally, the project required the removal of existing infrastructure and replacement of attenuation and flue systems. Modifications were also made to the mist and fire alarm systems in the generator room and adjacent areas. As part of the project, fuel in the bulk tank was polished and a new filtration system was installed.

The project faced significant challenges, as the two backup generators serve four buildings, each with its own electrical switch room. The installation required careful coordination with various stakeholders, including UCL, UCLH, Great Ormond St Hospital, and private contractors. Detailed method statements and logistics plans were developed, and programmes were detailed in hours to facilitate work during periods of low foot traffic. Factory visits and testing were conducted to ensure the new switchgear and generator worked perfectly, and to avoid delays to the programme.

Following completion, a detailed testing and commissioning programme was put in place, consisting of a series of on and offline tests. These tests included blackout tests, which involved switching all power to each building on and off to the generator. Due to the complex and aging mechanical and electrical infrastructure in the hospital, all shutdowns had to be carefully planned with specialists. This added to the complexity of coordinating work while ensuring the hospital remained fully operational.