Electricity use by data centres increased by almost a third last year alone as the sector expanded and activity increased.
The 31pc increase in demand in 2022 is just the latest in a series of annual increases which has seen the sector’s energy usage soar by 400pc in the last seven years.
The extraordinary growth of the sector is revealed in Central Statistics Office (CSO) figures which show it now accounts for 18pc of all electricity use recorded by ESB meters.
All urban residential meters together also account for 18pc of national electricity use – a total of just over 1.5 million households.
“In practice, a small number of data centres accounted for most of the metered electricity consumption,” the CSO said.
Rural households, which number around 666,000, were collectively responsible for 10pc of national electricity usage last year.
The remaining 54pc of usage was attributed to the commercial and industrial sector.
In total, 27pc of the country’s electricity demand came from industries classed as ‘large energy users’ which includes the biggest data centres but also high-energy users such as IT campuses and cement manufacturers.
Demand from the large energy user category has also grown substantially, increasing by 20pc last year and by 116pc over the last seven years.
Overall electricity usage nationally increased by 3.5pc last year.
At the same time, electricity use by households fell despite an increase in the number of homes.
Total demand for power in the residential sector dropped by 9pc last year and average usage per household fell by 12pc from 3,594 kilowatt hours (kWh) in 2021 to 3,177kWh.
No explanation for the drop is provided but it coincided with massive increases in electricity prices and government campaigns urging energy efficiency because of an energy shortage.
The CSO figures reveal there was still a major issue with unused or rarely used dwellings in the country last year as 13pc of residential customers used less than 1,000kWh in the year.
Holiday homes are believed to make up many of these accounts.
Sharp regional variations in electricity usage are also revealed. Homes in Leitrim, Donegal and Roscommon used the least electricity – as low as 2,516kWh on average in the year, while Meath homes used the most at 3,571kWh.
This likely reflects the greater use of solid fuels for heating in some counties.