20 Fenchurch Street, London.
Commission: Design and installation of 4 x 2280kVA enclosed dieselgenerator sets
Commencement date: January2011
Completion date: January 2014
Overview
In 2008, theoriginal25-storey tower block at 20 Fenchurch Street was demolished to make way for a new 36-storey building that would dramatically change the London skyline.
Designed by RafelVinoly, the structure increases in diameter as it rises up to the roof and because of this unusual design it has been nicknamed the ‘Walkie Talkie’ and ‘the building with more up top’.
When completed, it will become home to office and retail units and feature a ‘sky garden on the top floor offering the public a 160 metre high panoramic view of the City of London.
In 2011 Broadcrown secured the contract to provide 4 x 2280kVA generators providing stand-by power to the site. The generators are housed in a bespoke acoustically treated 30 metre long enclosure positioned on the roof of a 4 storey annex adjacent to the tower.
Also included within the Broadcrown scope of supply was a bespoke fuel system as well as remote fibre optic control panels positioned throughout the tower block to manage power distribution in the event of loss of mains supply.
Design & Build
The initial design concept was to supply 4 x diesel generators within 2 x double sound attenuated enclosures capable of providing a sound pressure level of 65dBA @ 1 metre.
Each generator is powered by a MTU 16V4000G63 engine coupled to a Cummins (Newage) HVSI 804T2 high voltage alternator.
With the power requirements pre-determined at tender stage one of the main design challenges was to ensure that the equipment could occupy and operate within extremely small spatial constraints.
Providing a fibre optic network of remote control panels positioned throughout the installation was both an electrical and mechanical challenge requiring detailed co-ordination with other trade contracts in order to define the complex routes for all the interconnections.
The generator fuel system also presented a challenge with the delivery of two bespoke fuel storage tanks which were lowered into level -2 basement area and routed to the bulk tank room. Access was extremely restricted it took precision planning to carry out these works. Once the tanks were in position we installed the fuel system which was routed through the building up to the generators on the Annex roof (level 4).
Each generator was assembled at our Hixon factory and fitted within a bespoke 30metre acoustically treated canopy.
Witness testing carried out at our plant at Hixon involved setting up temporary load banks. We also demonstrated the fibre optic network for the remote control panels.Witnessing was carried out in the company of Land Security/Canary
Wharf (Client) Hilson Moran Partnership (Consultant) and Dome (commissioning agent)
Witness testing was successfully completed over a period of 2 weeks
The units were then dismantled for transport to site and lifting into position.
Installation & Commissioning
The London 2012 Olympics coincided with the delivery programme and presented logistical challenges. All deliveries had to be fully co-ordinated with CWCL on site logistics team and routed through the city with the co-operation of local councils and the Metropolitan police.
Several of the 17 delivery vehicles were wide loads.
For the first part of the project we delivered of 2 x 27,000 litre bulk storage tanks each weighing 4.7Te to basement level B2 using the buildings overhead hoist installed in a lorry lift chamber. The bulk tanks were then skated and positioned into a bunded tank room and using hydraulic jacks the tanks were raised and lowered onto steel piers.
We then delivered and positioned the generators, acoustic enclosures, and radiators which were to be positioned on the 4 storey annex building roof adjacent to the main tower. The heaviest individual item to be lifted onto the roof was 15.8Te. To off-load the equipment we hired a 200Te mobile telescopic crane that remained on site for a period of 7 days. The crane was located between the main tower and the annex building.
Following lifting and re-assembly of the generator equipment, our electrical and mechanical installation engineers connected the site wide interfaces.
The mechanical installation works included:
• Double skinned welded fill & vent pipework from 2 x bulk tanks to fill point cabinet
• Single skinned welded dump pipework from customer’s connection to 2 x bulk tanks
• Double skinned/single skinned welded supply pipework from bulk tanks through duty/standby pump-set and to customer’s connection
• Single skinned screwed pipework for bulk tank polishing units
• Double skinned welded supply pipework from customer’s connection to generator enclosures
• Single skinned screwed fuel pipework in each enclosure
• 30mm, 50mm & 100mm mineral wool insulation c/w aluzinc cladding to roof mounted cooling pipework and exhaust pipework
The electrical installation works included:
• Electrical fitout of the enclosures small power and lighting
• MV cabling from the generator alternators to the local isolators
• Containment and control cabling from the generators to the generator remote control panels and master panel A on the annex roof level 4 control room
• Containment and control cabling from master panel A to the basement master panel B
• Installation of the generator MV neutral cables from the generators to the NEC panel on basement level 1
• Installation of all control wiring from master panel B to the generator MV switchboard
• Containment and control cabling within the bulk fuel tank room and up to the fill point cabinet
• Installation of a dual / redundant fibre optic ring installed via diverse routes throughout the building to various RIO panels. (Basement level to level 34)
Once the installation was tested and completed, our commissioning team started to power upthe equipment.
Following a strict site programme, the commissioning procedure included the installation of 9.9MVA temporary loadbanks, delivered to site on 5 x 40ft artic vehicles which had to be carefully positioned to ensure that the day to day running of the site could be maintained. We also co-ordinated the delivery to site of 45,000 litres of gas oil for generator commissioning.
After Market Service
Broadcrown will provide systemtraining with the site commissioning consultants and produce a comprehensive training video.
Broadcrown is committed to carrying out any ‘standstill’ maintenance requirements and project maintenance/warranty until March 2015.
We are also providing an extension on the maintenance/warranty until March 2015.
Contacts:
scroope design
courtmacsherry
bandon
west cork
tel +353 (0) 23 8853930
mob +353 (0) 87 2357538
[email protected]
www.scroope.com
