Supergrid transformer arrives in Sandford

178 tonne transformer is part of new Sandford substation

In a feat of logistical planning, National Grid has successfully delivered a new 178 tonne transformer to the 400,000-volt Sandford substation site it's building as part of the Hinkley Connection Project.

The Hinkley Connection Project is a new 57 km high-voltage electricity line that will connect six million homes and businesses to new sources of low-carbon energy. It will help the UK to meet ambitious targets to achieve net zero by 2050. The Sandford substation – one of 300 substations throughout England and Wales – is at the heart of the project.

The transformer will play a key role in changing the voltage at the Sandford substation, so that electricity can be supplied safely to homes and businesses or allow it to travel along National Grid’s network of overhead lines and cables.

Weighing in at 178 tonnes, the transformer weighs more than a blue whale (145 tonnes on average) and stands at 4.75 metres tall, meaning that it's nearly as high as a two-storey house. Heightening the logistical challenge, the critical piece of equipment measures 5.35 metres wide and 8.67 metres long.

Owing to its considerable size and weight, a specialist transport vehicle was used to safely deliver the transformer. The 70-metre-long transport vehicle collected the transformer from Dunball Wharf in Bridgwater, where it had been stored since making the journey from South Korea – where it was constructed – via Portbury Docks.

To reach Sandford substation, the transport vehicle travelled at 10mph on several A-roads, including the A39, A38 and A368 Dinghurst Road. In addition, the delivery route also saw the transport vehicle travel along the M5, where it reached a maximum speed of 15mph. Such low speeds are necessary to ensure the safety of all road users when transporting heavy loads.

Moving anything of this size and scale is always a challenge...

In May, National Grid will deliver a second piece of large electrical equipment to Sandford substation. This piece, known as a shunt reactor, will help to regulate voltage. Later in the year, another shunt reactor and transformer will then also be delivered to the site.

Michael Painter, Lead Project Manager for National Grid, commented: “The Sandford substation is the heart of the Hinkley Connection Project. The delivery of the transformer takes us one step closer to project completion and towards our goal of helping the UK to meet its net zero ambitions by 2050.

“The successful transportation of such a mammoth piece of equipment is testament to the hard work of our delivery team. Moving anything of this size and scale is always a challenge and when the item you’re transporting has travelled over 5,500 miles to get here and forms a key part of a major energy project the pressure is truly on.”

The 178 tonne transformer is transported

The transformer on its 70ft transport vehicle