Maintaining a secure electricity supply
How we work to ensure we continue to have enough electricity available to meet demand.
How the grid works
As the system operator, our role is to make sure that power can flow from where it is generated to where it is needed. Where possible, we always try and ensure we use as much renewable electricity as possible.
To do this, our expert grid engineers balance the demand for electricity with the generation that is made available to us by the companies who produce it every second of the day. This is a complex balance.
As well as having enough generation to meet electricity demand, it is also important that grid has additional services to ensure it remains stable. Both of these components are needed to ensure homes, farms, businesses and public services have a safe, secure and reliable supply of electricity when they need it.
How the grid is changing
Electricity systems across the world are changing. As we work together to decarbonise our societies and economies, our energy systems are moving away from their reliance on fossil fuel forms to cleaner, more renewable sources.
The electricity grid is vital infrastructure in all energy systems. This means we have to change how we operate the grid so it can work with more renewable sources of electricity which can be variable and dependent on the weather.
Managing a power system in transition
This transition can pose some short-term challenges to maintaining a secure supply of electricity. It is important we make changes to how we operate the grid safely and securely.
Like anything else, electricity is a precious resource. We need to work together to ensure there is enough supply for everyone who needs it when they need it.
Our Shaping Our Electricity Future Roadmap sets out our plan to change how we operate the grid to support the use of more renewable energy. In the future, this will involve incorporating new technologies such as long duration batteries to store renewable electricity when we don't need it so it can be used when we do.
Future outlook on electricity supply
All-Island Resource Adequacy Assessment
The All-Island Resource Adequacy Assessment
The All-Island Resource Adequacy Assessment (AIRAA) is an evolution of the Generation Statement Capacity (GCS) publication.
It looks at the balance between electricity demand and supply on the island of Ireland for the next ten years.
This annual publication helps industry, government, regulators, and other stakeholders facilitate the transition to renewable energy.
It supports future social and economic growth while ensuring the electricity system operates securely and resiliently.
Outputs from this assessment help shape the Single Electricity Market (SEM) Capacity Auctions. This system ensures that electricity supply in Ireland and Northern Ireland meets future demand.
All-Island Resource Adequacy Assessment 2025-2034
This All-Island Resource Adequacy Assessment provides a detailed look at how demand and generation may change from 2025 to 2034.
SONI and EirGrid have held two public consultations for the All-Island Resource Adequacy Assessment.
The first was about the methodology, and the second focused on the inputs and assumptions.
We thank our stakeholders in the energy industry for engaging with us during the consultation process to develop this new method.
All-Island Resource Adequacy Assessment 2025-2034 Main Report
All-Island Resource Adequacy Assessment 2025-2034 Data Workbook
More documentation is available below. This includes the final methodology, a detailed list of inputs and assumptions, and previous publications.
Supporting Documentation
2025-2034
AIRAA 2025-2034 Methodology Report
AIRAA 2025-2034 Inputs and Assumptions for Northern Ireland
AIRAA 2025-2034 Methodology Consultation Summary
AIRAA 2025-2034 Inputs and Assumptions Consultation Summary
2023-2032
GCS 2023-2032 Main Report Data Workbook
2022-2031
GCS 2022-2031 Main Report Data Workbook
System margins outlook
We publish the System Margins Outlook Report for Northern Ireland weekly. It gives information on:
- The dispatchable generation capacity expected to be available to meet peak demand
- The average and lower confidence renewables forecast
- The availability of our interconnectors to support trades if needed
Winter outlook
Demand for electricity is typically higher in the winter months. Our annual Winter Outlook publication sets out expectations for Northern Ireland’s electricity supply and demand across the winter period.
The publication is based on detailed research and analysis by SONI’s engineers. It shows whether we expect there to be enough electricity supply to meet demand this winter in normal operating conditions.
Mitigating challenges to the grid
Our team of expert engineers are always managing a degree of risk in operating the transmission system. We have tried and tested mitigation plans in place in the event any challenges arise.
Our plans include a mixture of outlook planning for demand, use of flexible technologies, emergency planning and developing the grid.
Resilience and emergency planning
We are always working to maintain a resilient power system. It's important that we continue to plan for increased demand and unexpected events.
There are different levels of alerts that we may issue on the grid, as part of either controlling demand or emergency response.