Transformer removals make way for next phase at Pelham Substation

Each of the removed transformers weighed approximately 180 tonnes and had been in service at Pelham for around 35 years.

The removal completes a major phase as National Grid upgrades and expands the existing substation. It clears the way for the next stage of construction and preparations for the arrival of two new quad boosters, which will allow the substation to transmit more electricity and support growing demand.

Removing equipment of this scale required careful planning by National Grid and its contractors, Murphy and Equans, with around 20 people involved in planning and carrying out.

The transformers were dismantled in a phased and controlled manner, with the work planned and carried out in accordance with approved safety procedures and industry best practice. The phased decommissioning took around one month for each transformer.

During the decommissioning process, the team inspected components inside the transformers to understand their condition and how they had performed over time. The findings will help inform the design and management of transformers in the future.

Once these inspections were complete, a heavy-lift crane was used to remove the main sections of each transformer. These were then loaded onto specialist heavy goods vehicles (HGVs) and taken off site for disposal and recycling, in line with all relevant environmental and regulatory requirements.

The team also removed supporting equipment, including the noise enclosure and air-insulated switchgear, as part of the works.

Karthik Ravikumar, Project Director at National Grid, said:

The transformer removals are a real milestone for everyone working at Pelham. Moving equipment of this scale takes a huge amount of planning, coordination and teamwork, with safety at the heart of everything we do.
“I’m proud of our National Grid colleagues and contractor teams who have worked together to reach this point safely. It is a tangible sign of the progress being made on site and clears the way for the next stage of construction, as we prepare for the new quad boosters.

With the existing transformers removed, work is now underway preparing the site for the two new quad boosters.
Quad boosters are specialised pieces of electrical equipment that help control the flow of electricity. The new units will increase how much electricity Pelham Substation can transmit and help keep the wider electricity system balanced.

Each new quad booster will weigh approximately 300 tonnes. Due to their size and weight, the equipment will be transported to Pelham in four separate heavy-lift movements. Each delivery will be carefully planned and coordinated to make sure it can be carried out safely, while minimising disruption to local communities and other works taking place on site.
Before the quad boosters arrive, teams will prepare the installation area, carry out piling and build the foundations for the new equipment.

The quad boosters are expected to arrive at Pelham between February and April 2027. 

Further work will continue at Pelham Substation as part of the project’s wider construction programme. This includes working with UK Power Networks to reroute a short section of overhead line and underground some cables, allowing 11 pylons around the substation to be removed.

The existing overhead line route between Pelham and Waltham Cross will also be upgraded with higher-voltage cables to support the increased capacity at the substation.

NLR is a major upgrade of the existing electricity network between Pelham and Hackney. The project will modernise substations that have been in use for more than 60 years and will double the capacity of existing overhead lines.

To find out more about the NLR and the latest updates, please visit the North London Reinforcement site.