Summer Outlook 2021

Our Summer Outlook report outlines Great Britain’s projected electricity needs for the summer ahead. ESO Director Fintan Slye explains how the report helps the industry prepare for the summer months ahead and the key messages of this year’s report.

As the Electricity System Operator, we are responsible for managing national supply and demand across Great Britain’s electricity network, every second of the day 365 days a year. This means that over the course of the year we face numerous different operating conditions as electricity use changes depending on the hours of daylight or temperature we all experience in our homes.

As we head into the brighter and warmer summer months, we produce a Summer Outlook report to communicate with the industry the conditions we expect to face as we move away from the darker, colder months of the Winter.

Whilst we expect that Covid-19 will continue to impact on how the country as a whole uses electricity, with most still working from home until June, we do not expect low demands to have the same impact on our networks this year. This is, in part, because over the last 12 months we have been working hard to ensure we don’t need to take the same actions we took last year (e.g. bilateral contracts with specific generators).

“I am extremely proud of the work our engineers have delivered over the last twelve months, alongside companies from across the industry to ensure that we can collectively minimise the impact of low demands this summer.”

We will continue to have available the ODFM service we created last year to facilitate distribution generators support balancing and system needs, but we do not expect to need to utilise it under normal conditions. Alongside this we have introduced a new Dynamic Containment service and accelerated the Loss of Mains Change Programme to ensure that the network is more resilient when facing low levels of electricity demand and inertia.

Key messages from the report:

  • Electricity demands  - We expect electricity demands to be less suppressed than summer 2020 and more in line with previous years.  We expect some continued impact on demand patterns due to COVID-19, with minimum demands forecast to be low again in 2021 but not as low as during the national lockdown of April and May 2020.​
  • Managing the system  - Managing low demand is one of the most complex scenarios our control rooms have to face and can require a greater number of actions to safeguard security of supply. ​We believe that we have the right tools and services available to manage system operability for the summer, including services introduced last summer such as ODFM and Dynamic Containment.
  • Risk reduction  - Our new Frequency Risk & Control Report provides industry with greater visibility of the risks we currently manage on the network, so we can work together to further minimise these risks in future.  The risk posed by vector shift protections was challenging last Summer. Working together with industry on the Accelerated Loss of Mains Change Programme we have been able to reduce the volume of generation using vector shift protection by half.

Read the full report here