ESO process for High Voltage and Stability Management overview

The high voltage and stability management NOA Pathfinders are two separate processes with different technical assessments. However, they share several similarities in the economic assessment and tender processes.

You can learn more about the NOA Pathfinders and participating on our Pathfinders section.

The objective of the process is to ensure economical and efficient options for high voltage and stability management will be available when required. This Electricity System Operator (ESO) led process is designed to identify high voltage and stability issues in the transmission system, the causes, requirements, and the preferred options to solve these issues. The process is designed to work with all expected option providers including Transmission Owners (TO), Distribution Network Owners (DNO) and Commercial Service Providers.

We carry out the voltage screening process annually, after the annual technical analysis of boundary capability is complete for the Electricity Ten Year Statement (ETYS) and Network Options Assessment (NOA).

For further detail see the ‘ESO process for High Voltage and Stability Management’ Section 6 of the NOA Methodology.

Learn more about the NOA methodology

National Grid ESO - Network Options Assessment NOA 2020 download - Turbines in sunset

The NOA process

Learn how and why the NOA Process is conducted each year. It includes how we evaluate onshore and offshore reinforcement options.


NOA for interconnectors

See how the NOA Process is conducted for interconnectors.


Suitability for third party delivery and tendering assessment

Learn more about how we apply the competition assessment criteria for NOA options


ESO process for high voltage and stability management

This section covers the NOA Pathfinder voltage and stability assessments.


Early development of options and Interested Person’s process 

Read how we increase the diversity of options considered by collaborating the use of the early development of options and IP process.


Network Options Assessment (NOA)

The NOA publication and associated information are available here