Residual waste inputs to the UK's 64 operational energy from waste facilities rose 1.6 per cent to 17.08 million tonnes in 2025, with growth slowing as new capacity continued to outpace demand, according to the annual UK Energy from Waste Statistics report published by waste market intelligence firm Refynix.

The report, which continues the series previously produced by Tolvik Consulting, covers all UK facilities designed primarily for the combustion of residual waste - both local authority collected and commercial and industrial material. Inputs for facilities operational throughout the year equated to 83.7 per cent of permitted capacity, down from 88.6 per cent in 2024. Total permitted capacity for fully operational plants reached 19.89 million tonnes per annum by December 2025, with a further 1.03Mtpa in late-stage commissioning and 4.11Mtpa under construction.

Refynix estimates that projected operational capacity for residual waste treatment at UK EfWs will reach 22.7Mtpa by 2030, up from a 22.0Mtpa estimate a year earlier. Applying the five-year average utilisation rate of 87.4 per cent to the 25.03Mtpa of certain total capacity (operational and in construction as at December 2025) suggests inputs could reach 21.9Mtpa once all current plants are fully built out.

Power steady, heat exports fall

Power exported to the grid held broadly stable at 10,049GWh, approximately 3.5 per cent of UK power generation. Average power export per tonne of waste fell modestly from 600kWh to 588kWh, consistent with lower utilisation and turbine availability issues that recurred across the fleet during the year.

Total heat exported for beneficial use dropped 10 per cent to 1,753GWhth, down from 1,946GWhth in 2024. Three of the four largest heat-exporting facilities recorded reductions of around 17 per cent, and across all EfWs heat exports were equivalent to 103kWhth per tonne of inputs, down from 116kWhth the previous year. Some new supply from recently completed plants partially offset the decline.

Turbine and generator availability was a recurring problem. Simple average turbine availability fell to 83.0 per cent from 86.6 per cent in 2024, with a number of facilities recording availability below 70 per cent. The parasitic load figure - the share of generated power consumed on site - rose to 17.1 per cent including power imports, up from 16.5 per cent.

Carbon emissions rise as ETS monitoring begins

Fossil CO2 emissions from the UK EfW fleet are estimated to have increased to 8.18MtCO2 in 2025, up from 7.63MtCO2 in 2024. Higher total waste inputs and a modest increase in average carbon intensity both contributed. The capacity-weighted average CO2 emitted per tonne of residual waste input rose to 1.05 tonnes, up from 1.00 in 2024, while estimated fossil CO2 per tonne reached 0.479 - the highest figure in the five-year series.

EfW operations are now confirmed for inclusion within the UK Emissions Trading Scheme. A two-year voluntary monitoring, reporting and verification period commenced on 1 January 2026, during which operators are invited to monitor, report and verify their emissions without incurring compliance obligations or financial exposure. The ETS Authority has indicated it will publish a second response confirming the full policy design, including cost exposure details, before the sector enters the full scheme.

In 2025, 26 sites measured biogenic content by radiocarbon C-14 analysis, up from 16 in 2024 - a rise Refynix attributes to operators preparing for the MRV requirements. Average reported biogenic content was broadly stable at 54.3 per cent, but measurement methodologies vary considerably across the fleet, and Refynix notes that standardisation of reporting protocols remains work in progress as ETS inclusion approaches.

Outage data published for the first time

For the first time, the report includes detailed analysis of planned and unplanned outage activity, drawing on improved data provided by operators in their Annual Performance Reports. Of the 59 EfWs reporting outage data, 11 did not undertake a major planned shutdown of two weeks or more during 2025.

Planned outage capacity was concentrated in the spring and summer months, consistent with the pattern seen over the 2020-2024 period. April recorded both the highest number of outage events and the greatest capacity under outage. Activity declined steadily from October through December as the fleet returned to fuller operation ahead of winter.

Total abnormal operating hours fell sharply to 159, down from 438 in 2024. The per-facility average dropped to 2.6 hours from 7.3 hours. Unlike the previous year, when a single facility accounted for 58 per cent of all abnormal hours, the 2025 total was more evenly distributed. Permit breaches continued to rise, reaching 433 instances from 399 in 2024, though Refynix notes a handful of facilities account for a disproportionate share of the total.

Waste composition and RDF exports

An estimated 74.1 per cent of EfW inputs in 2025 were derived from residual local authority collected waste, with commercial and industrial waste contributing 25.9 per cent. The share from C&I sources has risen over the long term, though the rate of change has slowed in recent years.

Average net calorific value of inputs for plants receiving untreated waste increased by 0.19MJ/kg to 9.81MJ/kg. Refynix identifies two countervailing pressures ahead. Mandatory household food waste collections in England, which commenced in March 2026, may reduce NCVs by diverting lower-calorific food waste from residual streams, while mandatory kerbside collection of plastic film packaging, required by March 2027, could have a similar effect by removing higher-calorific plastic. Difficult market conditions for plastic recyclers, however, may push more plastic into residual waste and support higher NCVs in the near term.

RDF and SRF exports fell 13 per cent to 1.87 million tonnes. Nine cement kilns in the UK accepted 602,000 tonnes of SRF under EWC code 19 12 10 in 2025, an increase of 3.1 per cent on the previous year.

Emissions compliance

Continuously monitored emissions to air remained stable at an average of 29.9 per cent of the Emission Limit Value, unchanged from 2024. Periodically sampled emissions showed improvement, with the fleet average falling from 21.5 per cent of ELV in 2024 to 17.2 per cent in 2025. Dioxins and furans fell to 35.3 per cent of ELV, while mercury and compounds fell from 21.4 per cent to 14.9 per cent.

Based on Environment Agency data and APR information, 43 EfWs with a combined permitted capacity of approximately 16.4Mtpa were accredited as R1 recovery operations as at April 2026, unchanged from the previous year.