Every day the ESO moves over 730GWh of high-voltage electricity around the country. That’s enough to power 146 billion light bulbs!

We ensure that Great Britain has the essential energy it needs by making sure supply meets demand every second of every day.

We move electricity through the system

The ESO moves high voltage electricity from where it’s generated, such as a wind farm, through the energy system. 

Using the infrastructure owned by the 3 transmission companies - National Grid Electricity Transmission, Scottish Hydro Electric Transmission Ltd. and SP Energy Networks, this high voltage electricity is passed onto one of the fourteen Distribution Network Operators across the country.

They own the local networks and convert it into a more manageable voltage that's suited for domestic use. Your local distribution network operator then feeds low voltage electricity through to your home or business property.

But who else is part of the British electricity system?

Today, the flow of electricity is getting more complex. This is because:

1. More renewable energy

We have a large and growing proportion of our electricity from renewables, and the amount of electricity generated varies depending on the weather.

2. A growing number of ways we can source electricity

Whereas before, we had a handful of mostly large transmission connected electricity generators, now there are 1000’s of decentralised generators (generation that is not connected to the transmission network, but rather on the distribution network or on site) as well, which is changing the pattern of electricity flows.

3. More ‘interconnectors’

Huge cables which allow us to trade electricity with other countries, are being built.

4. More participation in 'demand side response'

Large energy users, such as manufacturing plants, are incentivised to adjust how much electricity they use during peak times.


We manage the changing patterns of electricity demand and supply

Previously, large coal, gas and nuclear power plants were the main source of electricity, dominating Great Britain’s electricity generation market.

Electricity flowed from generation plants through the transmission network, to the distribution network and on to wherever it was needed.

The coal and gas plants were easily controllable and could be turned up or down in response to how much electricity was needed across the whole of Great Britain.

However, new forms of generation such as wind and solar are replacing these traditional plants.