SONI publishes Generation Capacity Statement 2023-2032

11 January 2024

SONI (System Operator for Northern Ireland Ltd.), the electricity transmission system operator for Northern Ireland, along with EirGrid, its counterpart in Ireland, have released the annual Generation Capacity Statement 2023-2032 (GCS).

The GCS, published annually, is an all-island study that sets out the likely balance between electricity supply and anticipated demand over the next ten years in order to signal future generation capacity needs to participants in the all-island electricity capacity market.

Like many parts of the world, Northern Ireland is undergoing a transition to a more sustainable and low carbon society, which requires a process of modernisation of the electricity grid that must be carefully managed. As more renewable energy generation becomes active, Northern Ireland will still require a base portfolio of cleaner conventional generation and energy storage solutions to stabilise and secure the system during periods of low wind or low sunlight.

The analysis contained within this year’s GCS is a clear signal to the electricity market that investment in new generation and the subsequent timely delivery of secured contracts will be required to ensure a stable and secure supply of electricity for consumers in both Northern Ireland and the Republic of Ireland.

The forecast for the next four years (2023-2026) previously indicated that the grid will require careful management, particularly during winter months when demand is typically higher.

However, since the analysis period was completed, SONI has been notified by a market participant of its request for a previously awarded project to be discontinued. This means there is a further opportunity for market investment in new generation capacity over the ten-year study duration.

As outlined in the GCS and SONI's Winter Outlook 2023/24, in normal running conditions there will be sufficient generation available to meet consumer demand throughout the winter period 2023/24, while recognising that there is an increased risk that the buffer margins for electricity generation may be tighter than normal and an increased dependency on wind and imports from GB.

On behalf of consumers, SONI continues to assess all cost-effective measures to ensure that Northern Ireland has adequate electricity supply over the coming years. As part of this process, SONI, alongside the Utility Regulator, runs capacity auctions annually and encourages the market to play an active role in developing future generation through investment.

SONI continues to work closely with the Department for the Economy, the Utility Regulator, our counterparts in Great Britain and the Republic of Ireland and the wider energy industry to find solutions to the challenges facing Northern Ireland and consider the range of mitigation measures available.

SONI Managing Director Alan Campbell noted, “The grid in Northern Ireland is undergoing a significant process of modernisation as we seek to decarbonise our society and economy. Northern Ireland is not an outlier here. While this is a very exciting time, it also presents a number of competing short-term challenges which SONI and all relevant stakeholders must work together to manage, including ensuring we have a base portfolio of clean conventional generation to ensure consumers have a secure, reliable supply of electricity during periods of low wind and solar generation.”

“Northern Ireland is well positioned to capitalise on these changing trends due to its natural resources and our expertise in technology and engineering. In line with Government targets, SONI is upgrading the electricity grid to support Northern Ireland’s renewable energy goals. With demand set to increase over the coming decade, this can only be achieved by timely investment and delivery of new generation by the market through the coming capacity market auctions.

“As Northern Ireland’s Transmission System Operator, SONI must manage the grid with the electricity that is made available to it by the market, balance the competing priorities and deliver a cost-effective system for consumers. The Generation Capacity Statement is a clear signal to the market that more generation is required, creating significant investment opportunities, to ensure a secure, reliable supply of electricity as we continue to progress the energy transition. We will continue to work closely with government and regulatory partners to identify the right solutions for homes, farms and businesses across Northern Ireland.” 

Campbell adds, “There are many reasons to feel confident and positive about the longer-term outlook. As consumers use electricity differently to enable productivity, new modes of transport and new ways to heat our homes, Government policies are expected to help guide us away from fossil fuels and towards a cleaner, cheaper and more secure energy future.”


The full GCS document can be found here.

In compiling the figures for the GCS, a ‘data freeze’ is employed. For this GCS, the data freeze date for the demand forecast was March 2023 and the generation forecast was May 2023. Importantly, this means there are likely to be some changes to the overall assessment if there have been developments between the ‘data freeze’ dates and publication date of the GCS. For this reason, SONI has developed a summary to the GCS this year which incorporates such developments; this is intended to reflect the most up to date adequacy forecast at the date of publication. The data freeze date for the summary is October 2023. The GCS is designed based on the best information available, although cannot account for changes within electricity supply.