Colchester Grid works
CASE STUDY: Substation Projects
EDF Energy approached Freedom with the view to increasing supply capacity at Colchester Grid substation in Essex.
| Client(s) | Edf Energy Networks |
|---|---|
| Location | Colchester |
| Project Start Date | March 2008 |
| Project Completion Date | September 2009 |
The Freedom design team, under the Professional Services Contract with EDF Energy, presented the option of increasing the 2 original 132kV/33kV 45MVA transformers with new 90MVA units.
Due to the increase in transformer output new through circuit 132&33kV cabling and overhead upgrade works were required and this facilitated the removal of the original oil filled 132KV cables. Freedom installed 132kV 200mm single core low smoke cable and completed the first sealing end installation if this type in Britain.
To assist EDF Energy in meeting their environmental targets we proposed that the new power transformers and auxiliary transformers be fitted with oil containment bunds.
Due to the size of the project it was split into two phases, namely T1B and T2B. Each phase being limited to a 6 month window period due to network constraints out of clock-change. Freedom designed, project managed, constructed and commissioned both new transformer bays in the allocated time slots.
The challenges other than the tight outage durations included:
- Demolition of the existing bases and fire walls
- Installation of 33 piles per transformer compound due to the poor ground conditions,
- Installation of precast interlocking fire walls
- Confined space basement works
- Road closure of very busy King Edward Quay
- Facilitation of 132KV overhead line work.
The relay control panels were all designed and constructed by Freedom Power Projects.
Due to the professional manner in which Freedom managed this Project, two additional bund retrofitting works were added to the scope at Colchester Grid.
Phase 1 works were commenced in March 2008 and completed in October 2008. Phase 2 started in March 2009 and will be fully complete by October 2009.
The commissioning of the second transformer T1B was completed on 4th Sept 2009 when the following pictures were taken.
