What is the National Grid?

What is the National Grid?

The National Grid is where E.ON Next sources the electricity that we supply to our customers. The National Grid transports the electricity safely from where it is made to where it is used. There are two main areas to the National Grid business that carry the electricity through different parts of its journey:

  • Electricity transmission

  • Electricity distribution

Both consist of a network of pylons, power lines, underground cables, and substations. You may have also heard of the National Grid Electricity System Operator (ESO) who are a legally separate business that manages how the electricity is moved through the grid.

Electricity transmission.

Electricity transmission is moving electricity from where it is generated (e.g wind farms and power plants) to where it is distributed. This is the first leg of the journey the electricity makes on its way into homes and businesses. The National Grid transmits electricity through 4,500 miles of overhead power lines and around 900 miles of underground cables. These high voltage (275kV or 400kV) networks are the ‘motorways’ that the electricity travels on to cover large distances.

Electricity distribution.

Electricity distribution is moving electricity from the transmission network into homes and businesses. This is the last leg of the journey the electricity makes on its way to customers. Electricity distribution networks are owned by a Distribution Network Operator (DNO). The National Grid is not the only DNO for our electricity. Since taking over Western Power Distribution in 2021, the National Grid distributes electricity to the Midlands, South West, and South Wales. Separate DNOs own electricity distribution networks in other regions of the UK. The pylons in distribution networks are smaller than in transmission networks as they carry electricity at a much lower voltage (from 132kV to just 230v). If transmission networks are high speed motorways then distribution networks are the winding web of country lanes that connect us all together.

What is a substation?

Substations convert electricity between different voltages using transformers. They are used in both the transmission and distribution networks. Transmission substations are the very first stop for electricity before it begins its journey through the National Grid. After electricity is generated (e.g at a wind farm) it passes through a substation to raise the voltage to either 275kV or 400kV. Distribution substations connect the transmission and distribution networks. They lower the voltage of electricity coming out of the transmission network so it is ready to be used when it is brought into our homes and businesses. Substations also contain specialist equipment to help manage current overloads caused by severe weather conditions or mechanical faults. This reduces the risk of power cuts to help keep our lights on.

Then what is the National Grid Electricity System Operator?

The National Grid Electricity System Operator (ESO) is a separate business that balances supply (how much electricity is generated) and demand (how much electricity is used) across Great Britain. They do not own or manage the physical network of pylons and cables that is used to transport the electricity. Instead, think of them as the SatNav the electricity follows to get to the right destination.

Why does the National Grid have international connections?

Despite being called the National Grid they currently own three international undersea connections to neighbouring countries – with three more being built. These are called electricity interconnectors. Trading electricity back and forth with our European neighbours gives us access to more renewable electricity sources when ours are not enough. Plus, we can make sure that renewable electricity does not go to waste when we are generating more than we need. By working together with our friends the National Grid we are helping to make our electricity more sustainable. At E.ON Next we provide 100% renewable* electricity to all our fixed tariff customers. Together with the National Grid we're working to improve GB energy security as part of the renewable energy transition - building a brighter energy future for everyone.

Contact our Energy Specialists if you’re having difficulty.

Our Energy Specialists are here to help you if you’re concerned about your energy bills. If you’re struggling to pay, please visit our help page to find out more about how we can support you. You can reach out to our Energy Specialists for personal advice on Facebook and X (Twitter).

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*Electricity backed by 100% renewable sources, E.ON's renewable generation assets, agreements with UK generators and the purchase of renewable electricity certificates. The electricity supplied to your home comes from the National Grid. Fixed term contracts only. Smart meter required, where eligible. Exit fees and T&Cs apply.

Published 27/10/2022