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System Operability Framework (SOF)

The System Operability Framework (SOF) takes a holistic view of the changing energy landscape to assess the future operation of Britain's electricity networks. The SOF combines insight from the Future Energy Scenarios with a programme of technical assessments to identify medium-term and long-term requirements for operability.

Evolving year-on-year 

Through extensive industry interaction, the SOF evolves year‑on‑year to meet changing operational and stakeholder needs.

Growth of low carbon and renewable generation, closures of conventional thermal power stations and changing interactions across the whole of the power system are just a few of the areas considered in the context of a rapidly changing power system.

Operability Strategy Report 2020​

The Operability Strategy Report summarises our work towards meeting the future operability challenges, the link to zero carbon operation, and how stakeholders can engage to help achieve this.

Operability Impact of Distributed Storage and Electric Vehicles

The high penetration of these devices would alter the demand seen by ESO control centre and impact the system operability. With appropriate market and framework design, storage and electric vehicles will be able to support electricity system operation and be enablers to the decarbonization transition.

Download the operability impact of distributed storage and electric vehicles document

Operating a Low Inertia System

We are always looking at how to best operate the network, as we see reductions in system inertia. We have processes in place for managing each operability challenge. We are already looking to address the future challenges we see ahead of us as we transition to a zero carbon system.

Download the operating a low inertia system document

Past Frequency Events

We control frequency by balancing electricity supply and demand. Occasionally we see a large loss of generation or demand which can cause a swing in system frequency. This report provides the brief summary of significant frequency events which has previously been provided in the System Incident report to the Grid Code Review Panel.

Download the past frequency events document

Impact of declining short circuit levels

We are identifying and quantifying system requirements which are affected by reductions in Short Circuit Level and we share some of our work in this document.

Download the Impact of declining SCLs document

Whole system short circuit level

Short circuit levels on the distribution networks are increasing driven by the growth in distributed generation and demand. This report looks at how these two trends interact and their net effect on the whole system.

Download the whole system SCL document

Regional Trends and Insights

Changes in the generation and demand are effecting how the power system is operated on a regional basis.

Find out about our latest analysis by downloading the report.

Download the regional trends and insights document

Voltage and Frequency Dependency 

Traditionally, voltage and frequency have been treated independently when considering operability. In the future, they will interact more.

Find out about our latest analysis by downloading the report.

Download the voltage and frequency document

Past SOF documents