Ryanair’s greenhouse gas emissions have increased again against a trend of reductions from most of Ireland’s other largest emitters.
The airline company’s carbon emissions grew to 12.3 million tonnes (mt) in 2025, a 2 per cent increase on 2024.
It now emits two-thirds more carbon than it did 10 years ago.
Its passenger numbers doubled in the same period, so emissions per passenger have fallen, but that still leaves the airline with its overall emissions moving in the wrong direction.
RM Block
The figures come from the latest report of the EU’s Emissions Trading System (ETS), which monitors the largest carbon polluters with an incentive and penalty scheme.
The scheme allocates free carbon allowances each year, allowing them to sell what they do not use but requiring them to buy allowances to make up for emissions in excess of their allocation.
Ryanair received 2.1mt worth of allowances last year, so it exceeded its allocation multiple times.
The airline did not respond to a request for comment but its director of sustainability, Steven Fitzgerald, told a recent podcast the company would spend €1.4 to €1.5 billion next year to comply with the ETS and a separate EU scheme requiring airlines to begin incorporating lower-carbon sustainable aviation fuels (SAF) into their jet fuel.
Ryanair’s chief executive, Michael O’Leary, was quoted in this weekend’s Sunday Independent as describing the ETS as “stupid” and “mad”.
He has repeatedly criticised it as unfair, as only flights within Europe are subject to it.
International flights come under a separate, voluntary, less onerous arrangement, although the EU is discussing extending the ETS to some international flights.
Ryanair has said it will continue to pursue reductions in per-passenger carbon intensity by using more modern aircraft, retrofitting existing craft and implementing more efficient fuel-use practices.
But Fitzgerald agreed, in the SimpliFlying podcast appearance, that the airline’s growth curve would be faster than its emissions intensity reductions for the foreseeable future.
“What Ryanair has gone through over the last few years is double-digit growth on an annual basis, and you’re not going to see the same declines in terms of emission intensity,” he said.
Carbon pollution from aviation is growing worldwide. Emissions from Aer Lingus flights within Europe rose by 2.4 per cent to 0.77mt last year.
The ETS figures show Ireland’s second largest emitter, ESB, had emissions of just over 2.09mt from its electricity generators at North Wall, Ringsend, Poolbeg and Corduff in Dublin; Aghada, Co Cork; Shannonbridge, Co Offaly and Moneypoint, Co Clare.
That was a 2 per cent reduction on 2024, mainly because the coal-burning station at Moneypoint ceased operating last June, although it remains on standby as a last-option source of emergency generation.
Irish Cement’s emissions rose at its Co Meath plant but fell at its Co Limerick plant, with combined emissions falling 3.7 per cent to just over 1.25mt.
Aughinish Alumina in Co Limerick, which refines the raw material for aluminium, fell by just over 1.5 per cent to 1.1mt.
For context, Ireland’s overall emissions in 2024, the last year available, were 57.65mt.
In total, 117 large industrial, manufacturing, pharmaceutical, food processing and power plants in Ireland reported to the ETS.
Their combined emissions fell by 5.5 per cent, below the EU average of 6.9 per cent.
Shipping came under the ETS for the first time in 2024 and an ETS2 is planned to cover fossil fuel use for land transport and heating buildings.
ETS2 was due to start next year but its introduction, postponed to 2028, is in doubt due to fears it will increase fuel costs to households and small businesses already suffering in the current energy crisis.
