SONI is responsible for the safe and secure operation of Northern Ireland’s electricity system to ensure power can flow from where it is generated to where it is needed. We do not generate or sell electricity.
Northern Ireland’s energy demands are monitored 24/7, 365 days a year by our Control Centre which carefully balances demand with available electricity generation on a minute-by-minute basis.
We manage the supply of electricity in real time, from electricity generators in Northern Ireland, as well as generators in the Republic of Ireland and through a subsea interconnector with Great Britain.
Every year, SONI forecasts future demand through the publication of the annual Generation Capacity Statement which sends signals to the all-island market for electricity about Northern Ireland’s future electricity requirements.
SONI plans and operates the electricity grid with the generation made available by the companies which secure contracts to generate electricity. We work closely with those companies to monitor their progress in delivering this new generation.
We also publish an annual Winter Outlook which assesses the balance between Northern Ireland’s expected demand and supply ahead of each Winter period.
When SONI issues a System Alert there is no immediate impact for users of electricity.
Instead, a System Alert warns of a heightened risk of potential temporary electricity supply issues in the near future, so that our expert engineers and those across the electricity sector can take pre-planned actions to protect the integrity of the grid.
It is a signal for all generators of electricity to make their power plants available for use and not to put their power plants at any risk of further breakdowns or operational challenges.
A System Alert can take place for a number of reasons and it is not an unusual event. They often pass off without incident once a sufficient buffer between electricity supply and demand is restored or standard operational protocols are maintained.
A System Alert (previously known as an Amber Alert) is the lowest level alert, followed by System Emergency (previously known as a Red Alert).
A System Alert can take place for a number of reasons and they are not unusual events in power systems across the world. When a System Alert is issued, that does not mean there will be any immediate interuption to the electricity supply.
Most often, they take place when the buffer between demand and the supply of electricity is tighter than normal. This is more likely during Winter months when demand for electricity is higher or during planned or unforseen outages at power stations or on interconnectors at any time during the year.
A System Alert can also take place when the power system is required to operate outside of normal technical operating standards, but where there is sufficient buffer between the demand and supply of electricity.
For example, there may be instances when the power system is operating with fewer large conventional generators than normal to accomodate planned maintenance or unforseen generator outages.
As Northern Ireland moves to a more renewables-based energy system, it is possible there will be more System Alerts in future years as we manage a power system which is transitioning away from large, conventional fossil-fuel generators to more weather-dependent sources of renewable generation.
Every year, SONI forecasts future demand through the publication of the annual Generation Capacity Statement which sends signals to the all-island market for electricity about Northern Ireland’s future electricity requirements.
SONI plans and operates the electricity grid with the generation made available by the companies which secure contracts to generate electricity. We work closely with those companies to monitor their progress in delivering this new generation.
We also publish an annual Winter Outlook which assesses the balance between Northern Ireland’s expected demand and supply ahead of each Winter period.
There are challenges in all complex electricity systems around the world from geo-political pressures, the weather (including very cold spells, storms, and periods of low wind), delays due to global supply chain challenges, to unforeseen outages at power stations and on interconnectors.
These challenges, which are often heightened in Winter in some parts of the world due to increases in consumer demand due to colder weather and darker evenings. This means that there is always some risk of potential disruption to the electricity supply.
Many other countries across the world are also upgrading their energy systems to reduce the use of fossil fuels to help tackle climate change, and help make them more robust and resilient by incorporating more renewable energy and new technologies to facilitate a wider range of electricity generation on the grid.
During this transition period, there may be some additional challenges, including balancing consumer demand with available electricity and the timing of new generation coming onto the system against the retiring of old generation.
Northern Ireland faces some of these challenges and risks like many other countries throughout the world.
On occasion, the buffer or margin between supply and demand can be smaller than normal, this could be due to a fault or planned outage at a power plant or if the wind isn’t blowing on a cold, dark winter day.
There may be other times when the power system is required to operate outside of technical operating standards, but where there is sufficient buffer between the demand and supply of electricity. For example, there may be instances when the power system is operating with fewer large conventional generators than normal to accomodate planned maintenance or unforseen generator outages.
All these challenges are being faced elsewhere – National Grid in GB, EirGrid in the Republic of Ireland and electricity system operators in Europe are all experiencing similar challenges as we move through the transition from systems reliant on fossil fuels to cleaner systems based on renewable energy.
As Northern Ireland moves to a more renewables-based energy system, it is possible there will be more System Alerts as we manage a power system which is transitioning away from large, conventional fossil-fuel generators to more weather-dependent sources of renewable generation.
New technologies currently being developed, such as long duration batteries and other low carbon grid technologies, will help ensure these challenges can be managed in the future.
When a System Alert is triggered and there is potential for disruption for electricity users, SONI will issue a notice on its website and social media channels. SONI's X (formerly Twitter) account will have the most up-to-date information during such a scenario. You do not need a twitter account to view this information. The Single Electricity Market Operator website will also carry notices about alerts on the grid. It is important to remember that most System Alerts pass off without any disruption to domestic electricity users.
A System Emergency State is much less frequent than a System Alert. It is issued by SONI when there is a high risk that not all electricity demand can be met. When the power system is in this state, SONI engineers will work closely with NIE Networks engineers to take pre-planned actions to protect the integrity of the grid. These actions may include implementing planned emergency power cuts for some users. A System Emergency is lifted once a balance between electricity supply and demand is restored.
The organisations that manage the electricity system on behalf of businesses and consumers, manage these risks on an ongoing basis.
Our experienced, expert grid engineers have tried and tested contingency plans in place to minimise the potential of any disruption including maximising existing generation availability, including the use of smaller, more responsive, open-cycle gas turbines, utilising new technologies such as batteries and maximising the availability of imports from Great Britain and the Republic of Ireland.
In the unlikely event there is a risk of more prolonged disruption, it may be necessary to take further steps to reduce demand to protect consumers and businesses. This may involve asking homes and businesses to voluntarily reduce their energy use during peak times, however this would only be implemented if necessary to protect homes and businesses from more prolonged disruption.
There is no immediate action required for consumers when a System Alert is issued as we do no anticipate any disruption to the electricity supply.
We encourage all homes and businesses to think about their contingency plans in the event of temporary disruption to electricity, due to storms, weather or supply issues.
It is important to reassure customers that whilst there are some increased risks in Winter, SONI forecasts show that there is sufficient generation to meet consumer demand in expected operating conditions and there are robust plans in place to minimise any risk of disruption.
In the instance of a more challenging situation, for example due to an unforseen generator breakdown, consumers may be asked to be conscious of their use or reduce it at peak times to ensure there is enough electricity for everyone.
In the unlikely event of a System Emergency, SONI’s license obligates SONI to instruct NIE Networks to implement planned emergency power cuts to protect the integrity of the power system and prevent a more serious event. If this happens, some customers may experience temporary planned emergency power cuts. By doing this we remain in control of the grid and avoid the risk of extensive unplanned interruptions of electricity supply. In such situations, SONI and NIE Networks will work to make planned emergency power cuts as short-lived as possible and will rotate the locations that are impacted by them. If you think you are experiencing a planned emergency power cut, please visit https://powercheck.nienetworks.co.uk/ for up-to-date information. For more information, visit NIE Networks website here.
Planned emergency power cuts are a measure of last resort, put into operation when we need to take action to protect the integrity of the power system during a System Emergency State. In this scenario, deliberate measures are taken by expert engineers to interrupt power supply to a portion of electricity users, for a set period of time, to reduce electricity use when the supply of electricity cannot meet demand. Plans, approved by the Utility Regulator, are in place to undertake such planned emergency power cuts, while protecting the supply of electricity to critical infrastructure such as hospitals.
A blackout occurs when there are electricity power cuts across a widespread area in an uncontrolled manner. One of the reasons that planned emergency power cuts are put into operation is to avoid widespread blackouts. Plans, approved by the Utility Regulator, are in place to undertake the restoration of supply to customers after a System Blackout State, in the unlikely event of this occurring.
It is important to be clear that the probability of any mass, unplanned blackouts in Northern Ireland is very low and is highly unlikely.