Northern Ireland exported more residual waste in 2025 than the year before, the only part of the UK to do so, even as the country as a whole reduced its reliance on shipping waste abroad. Figures published by the waste-sector advisory firm Refynix show Northern Ireland exported around 302,000 tonnes of residual “black bin” waste during the year, up from 289,000 tonnes in 2024, accounting for roughly 16 per cent of the UK total despite the region holding under 3 per cent of the UK population.
The data appears in Refynix’s annual UK Energy from Waste Statistics report, which continues a series previously published by Tolvik Consulting. Total UK exports of Refuse Derived Fuel and Solid Recovered Fuel fell 13 per cent year on year to 1.87 million tonnes, the first reduction since 2021, a fall the report links to new domestic treatment capacity coming online. Northern Ireland moved in the opposite direction, and its growing dependence on export markets leaves councils exposed to factors largely outside their control: shipping costs, the capacity of European facilities to receive the material, and the policies of receiving countries.
A widening gap with the rest of the UK
The contrast with the other devolved nations is clear. Scotland’s exports fell steeply over the year, from 100,000 tonnes to an estimated 25,000 tonnes, while Wales held broadly steady at around 47,000 tonnes. England, the largest exporter, fell from 1.73 million to 1.50 million tonnes. Northern Ireland’s rising figure makes it the outlier.
The report records 64 fully operational Energy-from-Waste (EfW) plants across the UK at the end of 2025, with further capacity in construction or commissioning. EfW facilities recover energy from waste that would otherwise be landfilled: the UK fleet exported around 10,000 gigawatt hours of electricity and 1,753 gigawatt hours of heat for beneficial use during the year. Northern Ireland has one operational EfW, the Full Circle Generation facility in Belfast, which processed around 135,000 tonnes in 2025, but no large-scale plant capable of treating the council-collected residual black bin waste that makes up the bulk of the export trade. Most of that exported waste, more than 85 per cent, leaves through Warrenpoint Port.
- Northern Ireland: approximately 302,000 tonnes exported in 2025, up from 289,000 tonnes, the only UK nation to increase
- Scotland: approximately 25,000 tonnes, down from 100,000 tonnes
- Wales: approximately 47,000 tonnes, broadly unchanged
- England: approximately 1.50 million tonnes, down from 1.73 million tonnes
- UK total: 1.87 million tonnes, down 13 per cent, the first fall since 2021
Indaver, the waste management company behind the proposed £250 million arc21 residual waste treatment project, has pointed to the figures as evidence that Northern Ireland needs to develop its own treatment capacity. Colin O’Hanlon of Indaver said Northern Ireland is becoming an outlier in UK waste management:
“There is chronic under-capacity in the Northern Ireland waste management sector for our black bin waste, and this latest independent data proves we are lagging significantly behind the rest of the UK and Europe in adopting the modern infrastructure necessary to address this growing challenge. We have been saying for some time that continued inaction means we are nearing a tipping point where we are increasingly vulnerable and risk adding a waste crisis to our existing wastewater infrastructure crisis.”
Successive Northern Ireland waste strategies have treated energy recovery as preferable to landfill, and have regarded waste export as an interim measure rather than a permanent arrangement. On that basis, the absence of a large-scale local facility leaves the region dependent on a model its own policy framework was not designed to rely on indefinitely.
What the report says about capacity
The same report also carries a finding that bears on how much new capacity is needed. Across the UK, EfW waste inputs grew by just 1.6 per cent in 2025, slower than in recent years, while permitted capacity continued to expand. Plants operational throughout the year ran at 83.7 per cent of permitted capacity, down from 88.6 per cent in 2024. Applying the fleet’s five-year average utilisation to all capacity either operational or under construction, Refynix estimates built-out inputs of around 21.9 million tonnes a year against a “certain” permitted capacity of just over 25 million tonnes, and summarises the national position as capacity beginning to outpace demand.
How that national picture applies to Northern Ireland specifically is contested. Supporters of local infrastructure argue that exporting waste long distances is not a sustainable substitute for treating it close to where it arises, regardless of the UK-wide capacity total. Opponents argue that the same data is a warning against building more large-scale capacity than the residual waste stream requires. Both readings draw on the same report.
The arc21 project and its planning history
The proposed arc21 facility, a residual waste treatment plant for the former Hightown Quarry at Mallusk, County Antrim, would serve six councils in the east of Northern Ireland: Antrim and Newtownabbey, Ards and North Down, Belfast, Lisburn and Castlereagh, Mid and East Antrim, and Newry, Mourne and Down. Together those councils account for around 60 per cent of Northern Ireland’s municipal waste.
The project has been in and out of the planning system for more than a decade. A first application was lodged in 2014. Environment Minister Mark H Durkan refused it in 2015; that refusal was successfully appealed, and in 2017 a senior civil servant granted approval in the absence of a sitting minister, a decision later overturned in the courts. In March 2022, Infrastructure Minister Nichola Mallon refused permission again, citing thousands of public objections and a concern that the facility could increase the market for waste disposal and discourage recycling.
Indaver and arc21 challenged that 2022 refusal. In May 2023, Department for Infrastructure officials, operating in the absence of an Executive, invited the High Court to quash Mallon’s decision, accepting it had not been accompanied by sufficient rational reasons. The court quashed the refusal, though this did not grant the project permission: it returned the application to the Department to be considered afresh. Updated environmental information was lodged in 2025 to allow statutory consultees and the Department to formulate a recommendation, and a fresh ministerial decision is still awaited.
Indaver describes the project as a solution that is ready to proceed. O’Hanlon said:
“Unlike the current wastewater infrastructure crisis, there is a ready-made solution waiting to be implemented. That solution is the £250 million arc21 residual waste project, which presents an opportunity for Northern Ireland to catch-up with the rest of the UK and Europe. The project simply requires a Department for Infrastructure (DfI) Ministerial approval in the near future. This will allow it to progress to the next stage of procurement where a business case evaluation will trigger a democratic decision by the arc21 councils to decide if it progresses.”
The project’s backers note that it would be delivered through private investment and would leave a publicly owned asset, and that, if approved, the final commitment of public funds would still rest with a vote of the six arc21 councils. The decision now before the Department is a fresh determination of the application rather than a sign-off of a previously settled scheme.
Opposition and the question of need
The arc21 proposal has also drawn sustained opposition. Thousands of objections have been lodged over the years, and a community campaign, NoArc21, has run since the early stages. When permission was refused in 2022, the minister cited roughly 5,000 objections. In 2021, ten Northern Ireland MPs across several parties wrote raising concerns about the project, and the BBC’s Spotlight programme reported that Antrim and Newtownabbey Borough Council, the council area where the facility would be built and itself an arc21 member, had indicated it no longer wished to take part, citing cost and whether the plant was still needed.
Opponents of new incineration have argued that, with the UK fleet already running below permitted capacity, building further large-scale capacity risks oversupply that can lower gate fees and weaken the incentive to extract recyclable material. Supporters counter that the relevant comparison is not UK-wide capacity but the absence of any large-scale facility in Northern Ireland itself, and that recovering energy from local waste locally is preferable to shipping it abroad. The disagreement over need has run alongside the project for most of its history and is unlikely to be fully resolved by a single planning decision.
Warrenpoint, market volatility and a coming carbon cost
The export model also carries practical strains at the point of departure. Warrenpoint Port, which handles most of Northern Ireland’s RDF exports, has faced sustained complaints from nearby residents about odour. An independent environmental audit identified issues including out-of-date and compromised bales and storage outside licensed areas, while noting improvements following operational changes by the main exporter, Re-Gen. O’Hanlon has linked the difficulties at the port to the wider reliance on exporting waste:
“Waste exporting is a notoriously complex process involving many movements of waste on roads and ships and which requires port infrastructure and storage. It is our view that the issues being experienced over recent years in Warrenpoint are a direct symptom of the risks associated with this process and our wider reliance on waste export.”
O’Hanlon also argued that international markets are becoming less reliable, citing weather-driven demand and the taxing of RDF imports by some receiving countries.
The economics of waste treatment are set to change on both sides of the equation. The Refynix report confirms that EfW operations are being brought within the UK Emissions Trading Scheme, with a two-year voluntary monitoring period having begun in January 2026 ahead of full inclusion, and records estimated fossil carbon emissions from the UK EfW fleet rising to 8.18 million tonnes of CO2 in 2025. A carbon price on burning residual waste will bear on the running cost of any new domestic facility, including arc21, while the same pressures and possible import taxes abroad affect the cost and reliability of continued export.
Questions that remain
- What is the timeline for the Department for Infrastructure’s fresh planning decision on the arc21 application, following the 2023 quashing of the previous refusal?
- Do all six arc21 member councils still support the project, given previously reported reservations from at least one member council?
- How should the UK-wide trend of capacity outpacing demand be weighed against the absence of any large-scale treatment facility in Northern Ireland itself?
- How will the inclusion of Energy-from-Waste in the UK Emissions Trading Scheme affect the comparative cost of local treatment against continued export?
- Why has Northern Ireland’s recycling rate lagged behind Wales, where the local-authority rate reached 68.4 per cent in 2024-25, and would improving it reduce the residual waste requiring treatment or export?
- What contingency exists for councils if the arc21 project is not approved, or if European export markets tighten further?
Northern Ireland’s reliance on exporting its residual waste is rising while the rest of the UK reduces its own, and the gap raises a genuine question about how the region treats the waste its policy framework expects it to handle closer to home. Whether the answer is the arc21 facility, alternative infrastructure, or higher recycling rates that shrink the residual stream, the most significant treatment scheme to reach the Northern Ireland planning system now rests on a ministerial decision that remains outstanding.
The full Refynix report, UK Energy from Waste Statistics 2025, is available free of charge via refynix.uk. Indaver’s infrastructure assessment, “Tipping Point: NI’s Looming Waste Crisis,” is available at becon.co.uk.