A 4-year project has involved Western Power Distribution (WPD) upgrading a major substation in the center of Gloucester, UK, and installing 1km of 132-kV cable to connect it to an existing substation dating back to the 19th century at Castle Meads, where a new transformer has also been installed.
The work will allow for new load growth and will also help to safeguard supplies to the existing homes and businesses in the area, following the regeneration of the historic docklands area.
“It ensures that we can provide a high level of service to Gloucester long term, by improving the infrastructure and security of our electricity network,” said Jane Rawlings, WPD’s Projects Team Manager for the area.
WPD’s Project Engineer James Moten who has overseen the work said: “The substation is in a conservation area and the council was keen to retain as much of its character as possible. Several redundant buildings including the original power station had to be demolished to make room for the new electrical equipment. However we were able to retain one of the original office buildings and refurbish it, so that it could house some of the equipment.
“It was thought that the original building dated back to the 1890s, but during the refurbishment work we discovered that it had a vaulted cellar which had been colonized by bats. Experts suggest the cellar could date back to the 18th century. It has been a very interesting process and we have found out lots of history about the area.
“Plans also revealed that the substation site is built on top of a Roman settlement and a medieval castle, so all excavations were closely monitored by archaeologists from English Heritage and Gloucester City Council Archaeological Department. Several Saxon and Roman artefacts were discovered during the course of the work.”
Not least among the challenges for the team on this project was the discovery of bats in one of the old substations buildings. Since bats are a protected species, all work had to stop to allow monitoring to take place over a number of months until the creatures were ready to move out. Twelve months later, the bats decided to do just that and the demolition work could begin.
A number of abandoned electrical cables were also removed from the site - some from 1899 when the first substation was established on the site.
With the site prepared, 1km of cable was laid to connect the substation up to the existing grid site at Castle Meads. But its location on the opposite side of the River Severn presented further challenges.
WPD’s Senior Wayleave Specialist Arthur Jones explained: “The ownership of the riverbed and neighboring land was initially in dispute and this had to be resolved before permission to cross it could be obtained. There were also numerous unknown landowners along the cable route that had to be tracked down as well as access and party wall issues to resolve on the substation site itself.
“Thanks to the perseverance of the wayleave team, the issues were all resolved so that the project could progress.”
The final stage of the project saw the installation and connection of the new electrical equipment at both substations which concluded the 4-year project.