System Operator signals generation investment opportunity over next decade

SONI publishes All-Island Resource Adequacy Assessment

Northern Ireland’s independent Transmission System Operator, SONI (System Operator for Northern Ireland), has published the All-Island Resource Adequacy Assessment  which assesses expected electricity demand and outlines the investment opportunities for the generation, storage, and interconnection capacity needed on the island of Ireland over the next ten years to keep the electricity supply secure and to support social and economic growth.

As the System Operator, SONI does not generate or sell electricity. Rather, the System Operator’s role is to operate the high-voltage electricity grid (transmission system) in real-time to balance demand for electricity with the generation made available by the private companies who secure contracts through the all-island Single Electricity Market.

As part of this role, the System Operator also undertakes detailed assessments to understand how much generation is required to meet consumer demand in the future.

The purpose of the All-Island Resource Adequacy Assessment is to provide investment signals to the all-island markets on how much generation Northern Ireland requires to meet demand over a ten-year period. The assessment will allow industry, government, regulators and other stakeholders to facilitate the transition to renewable energy, supporting social and economic growth into the future, whilst ensuring the secure and resilient operation of the electricity system. 

The study deploys two scenarios measured against several possible demand growth assessments. The Base Scenario considers how much generation Northern Ireland requires in normal operating conditions. The Secure Scenario considers this in the context of more challenging conditions such as low levels of imports via interconnectors.

Under the Base Scenario, the study shows that Northern Ireland will have sufficient generation to meet demand until year 2031 of the study period, with an investment opportunity for 30-120 MW from 2032 onwards. Under the Secure Scenario, the study shows additional investment requirements of up to 200MW between 2026-2031, rising to 320 MW by 2035. 

In the report, SONI confirms its assessment that the Secure Scenario is most prudent and should be adopted for decisions relating to securing capacity for the continued secure and reliable operation of the power system.

There will be several Capacity Market Auctions in the coming years where private companies will have the opportunity to secure contracts to provide additional electricity generation to meet the growth in demand.

SONI Chief Executive, Alan Campbell, said: 

“As the System Operator, our role – alongside operating the electricity grid in real time with the generation available to us – is to forecast future electricity demand and determine the level of generation Northern Ireland will need to meet it. 

Mr Campbell continues: “Our studies indicate that Northern Ireland is forecast to have sufficient generation to meet demand under normal operating conditions for most of the coming years, with a small amount of additional capacity required in the early part of the next decade. However, to operate with a higher level of security – particularly in the face of potential issues such as unexpected generator outages – our assessment shows that further investment in new generation will be needed over the coming years.

“While our analysis does highlight some short‑term challenges, we will continue to work closely with the Utility Regulator, the Department for the Economy and the wider energy industry to ensure Northern Ireland continues to have a safe, secure and reliable electricity supply.”

SONI’s Director of Networks and Innovation, Gerard Carlin, said:

“Running any power system is naturally complex, particularly as we transition toward an energy landscape with more renewable and intermittent generation. As the System Operator, we must account for a wide range of variable – and often competing – factors when developing the forecasts that shape Northern Ireland’s future energy needs.

“It is essential that we provide clear signals to the market about the level of generation required to maintain a safe, reliable and secure electricity supply for homes, businesses, farms and public services across Northern Ireland. At the same time, we must balance this with the need to keep costs as low as possible for consumers, who ultimately pay for this generation through their bills. We will continue to work closely with the Utility Regulator and the wider energy sector to ensure the market understands the need for future investment.”

The Assessment also models future growth in electricity demand based on available evidence and projections in areas such as economic growth, new technology loads and the electrification of sectors such as heat and transport. 

The study demonstrates a slower than previously expected growth of total demand in the next few years before total demand increases as predicted towards the end of the 10-year study period.

The adequacy position, the balance of demand and supply, is measured against a standard set by the Department for the Economy known as the Loss of Load Expectation. This standard for Northern Ireland is set at 4.9 hours. 

The study suggests that Northern Ireland could experience an increased risk to security of supply in the event of unforeseen generator or interconnector outages, especially during period of low renewables. The System Operator continues to work closely with the Department for the Economy and the Utility Regulator on a range of mitigation measures.

This year’s assessment also includes a new Economic Viability Assessment. This is part of a phased pathway towards full incorporation into next year’s adequacy assessment.

You can read the All-Island Resource Adequacy Assessment here.