Households must reduce their energy use between 5pm and 7pm each day to avoid blackouts this winter, the energy regulator has warned.
The Commission for the Regulation of Utilities (CRU) said it must "act quickly" to secure energy supply due to the significant risks to the country's electricity network.
The CRU has launched a two-week consultation asking industry and electricity providers how they intend to reduce energy usage.
In a document sent to electricity companies and seen by the Irish Examiner, the regulator said it was set to introduce changes to tariffs from October 1st.
The CRU said what it was proposing meant “extra-large energy users” such as data centres and other industries faced a higher increase to their bills.
The plans would also see those industries penalised for failing to reduce demand when winds are low and renewable energy supply dips.
Electricity supply companies may also charge households more for electricity used between the hours of 5pm to 7pm, according to the Economic and Social Research Institute (ESRI).
Muireann Lynch, an energy economist at the ESRI, said energy supply companies have yet to decide how they will recoup the extra charges they are facing from their customers.
“Obviously the first thing they're going to want to do is for us to reduce our usage. And then for any remaining charge they face, it is essentially a question of how they recoup that charge. Do they do it through a fixed portion of people's bills, or do they adjust the tariffs?” Ms Lynch told RTÉ radio’s Morning Ireland.
Households with smart meters who are on smart tariffs or “time of use” tariffs could be hit with further increases in their already higher peak-time charges, compensated for by greater off-peak reductions.
Families are already paying an average of €900 more a year for their electricity and €800 more for their gas than they were at the start of 2021.
The country's electricity demand is expected to increase by 13 per cent between 2021 and 2025 but more than half of that rise (62 per cent) is set to come from a few “extra-large energy users” such as data centres.
CRU said the risks to Ireland’s energy system are not directly caused by any one sector, but the “significant demand growth” from extra-large energy users such as data centres is a “significant contributing factor”.
Paul Deane, research fellow at University College Cork, said the intervention from the regulator pointed to the seriousness of the situation Ireland is facing.
“The consequence of any interruption of electricity supply would be catastrophic,” he told the Irish Examiner. “This is sending the correct signals to the correct areas of the market, the areas putting the most stress on the system, and targeting them for these financial measures.
“It puts the financial measures on those with the most responsibility for driving all these challenges. But we’ll have to wait and see the impact on data centres. Will the tariffs they’re charging incentivise them to change their behaviour enough?” – Additional reporting: Vivienne Clarke